REVIEW

2018
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REVIEW

NUCLEAR POSTURE REVIEW

FEBRUARY 2018

OFFICE OF THE SECRETARY OF DEFENSE
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REVIEW

CONTENTS

SECRETARY’S PREFACE ......................................................................I

EXECUTIVE SUMMARY ......................................................................V

Introduction............................................................................................................. V

An Evolving and Uncertain International Security Environment .............................................. V

The Value of U.S. Nuclear Capabilities............................................................................ VI

U.S. Nuclear Capabilities and Enduring National Objectives .................................................VII

Deterrence of Nuclear and Non-Nuclear Attack.................................................................VII

Assurance of Allies and Partners...................................................................................VIII

Achieve U.S. Objectives Should Deterrence Fail ...............................................................VIII

Hedge against an Uncertain Future................................................................................. IX

U.S. Nuclear Enterprise Personnel................................................................................. IX

The Triad: Present and Future ...................................................................................... IX

Flexible and Secure Nuclear Capabilities: An Affordable Priority ........................................... XI

Enhancing Deterrence with Non-strategic Nuclear Capabilities............................................... XI

Nuclear Command, Control, and Communications Modernization.........................................XIII

Nuclear Weapons Infrastructure.................................................................................. XIV

Countering Nuclear Terrorism .................................................................................... XV

Non-proliferation and Arms Control ............................................................................ XVI

I. INTRODUCTION TO U.S. NUCLEAR POLICY AND STRATEGY .............. 1

II. AN EVOLVING AND UNCERTAIN INTERNATIONAL SECURITY 

ENVIRONMENT ................................................................................5

The Return of Great Power Competition...........................................................................6

Other Nuclear-Armed States Have Not Followed Our Lead ....................................................7

Russia......................................................................................................................8

China.................................................................................................................... 11

North Korea............................................................................................................ 11

Iran ...................................................................................................................... 13

Uncertainties Regarding the Future Security Environment and the Threats it May Pose ................. 13
III. WHY U.S. NUCLEAR CAPABILITIES? .............................................. 15

U.S. Nuclear Capabilities............................................................................................ 16

IV. ENDURING NATIONAL OBJECTIVES AND THE ROLES OF NUCLEAR 

WEAPONS IN U.S. NATIONAL SECURITY STRATEGY........................... 19

Deterrence of Nuclear and Non-Nuclear Attack................................................................. 20

Assurance of Allies and Partners.................................................................................... 22

Achieve U.S. Objectives Should Deterrence Fail ................................................................ 23

Hedge against an Uncertain Future................................................................................. 24

V. TAILORED STRATEGIES AND FLEXIBLE CAPABILITIES ..................... 25

Tailored Deterrence .................................................................................................. 26

Flexible Capabilities .................................................................................................. 26

VI. U.S. STRATEGIES TO COUNTER CONTEMPORARY THREATS........... 29

A Tailored Strategy for Russia ...................................................................................... 30

A Tailored Strategy for China....................................................................................... 31

A Tailored Strategy for North Korea .............................................................................. 32

A Tailored Strategy for Iran ......................................................................................... 33

Extended Deterrence and Tailored Assurance ................................................................... 34

Hedge against Diverse Uncertainties............................................................................... 37

VII. CURRENT AND FUTURE U.S. NUCLEAR CAPABILITIES .................. 41

U.S. Nuclear Enterprise Personnel................................................................................. 42

The Three Legs of the Strategic Nuclear Triad................................................................... 44

The Department of Defense Replacement Program............................................................. 48

Flexible and Secure Nuclear Capabilities: An Affordable Priority ........................................... 51

Enhancing Deterrence with Non-Strategic Nuclear Capabilities .............................................. 52

Nuclear Command, Control, and Communications (NC3) Modernization ................................. 56

VIII. NUCLEAR WEAPONS INFRASTRUCTURE..................................... 59

IX. COUNTERING NUCLEAR TERRORISM.......................................... 65

X. NON-PROLIFERATION AND ARMS CONTROL................................ 69

Non-Proliferation and the Nuclear Non-Proliferation Treaty................................................. 70

Arms Control.......................................................................................................... 72
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NUCLEAR POSTURE REVIEW

Secretary’s Preface

On January 27, 2017, the President directed the Department of Defense to conduct 

a new Nuclear Posture Review (NPR) to ensure a safe, secure, and effective nuclear 

deterrent that protects the homeland, assures allies and above all, deters adversaries. 

This review comes at a critical moment in our nation’s history, for America confronts 

an international security situation that is more complex and demanding than any since 

the end of the Cold War. In this environment, it is not possible to delay 

modernization of our nuclear forces if we are to preserve a credible nuclear 

deterrent—ensuring that our diplomats continue to speak from a position of strength 

on matters of war and peace.

For decades, the United States led the world in efforts to reduce the role and number

of nuclear weapons. The 1991 Strategic Arms Reduction Treaty (START) set a 

ceiling of 6,000 accountable strategic nuclear warheads – a deep reduction from Cold

War highs. Shorter-range nuclear weapons were almost entirely eliminated from

America’s nuclear arsenal in the early 1990s. The 2002 Strategic Offensive Reduction 

Treaty and the 2010 New START Treaty further lowered strategic nuclear force 

levels to 1,550 accountable warheads. During this time, the U.S. nuclear weapons 

stockpile drew down by more than 85 percent from its Cold War high. Many hoped 

conditions had been set for even deeper reductions in global nuclear arsenals, and,

ultimately, for their elimination.

While Russia initially followed America’s lead and made similarly sharp reductions in

its strategic nuclear forces, it retained large numbers of non-strategic nuclear 

weapons. Today, Russia is modernizing these weapons as well as its other strategic 

systems. Even more troubling has been Russia’s adoption of military strategies and 

capabilities that rely on nuclear escalation for their success. These developments,

coupled with Russia’s seizure of Crimea and nuclear threats against our allies, mark 

Moscow’s decided return to Great Power competition.

China, too, is modernizing and expanding its already considerable nuclear forces. 

Like Russia, China is pursuing entirely new nuclear capabilities tailored to achieve 

particular national security objectives while also modernizing its conventional 

military, challenging traditional U.S. military superiority in the Western Pacific.

Elsewhere, the strategic picture brings similar concerns. North Korea’s nuclear 

provocations threaten regional and global peace, despite universal condemnation in 

the United Nations. Iran’s nuclear ambitions remain an unresolved concern. 

Globally, nuclear terrorism remains a real danger.
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We must look reality in the eye and see the world as it is, not as we wish it to be. 

This NPR reflects the current, pragmatic assessment of the threats we face and the 

uncertainties regarding the future security environment.

Given the range of potential adversaries, their capabilities and strategic objectives, 

this review calls foraflexible, tailored nuclear deterrent strategy. This review calls for 

the diverse set of nuclear capabilities that provides an American President flexibility 

to tailor the approach to deterring one or more potential adversaries in different 

circumstances.

For any President, the use of nuclear weapons is contemplated only in the most

extreme circumstances to protect our vital interests and those of our allies.

Nuclear forces, along with our conventional forces and other instruments of national 

power, are therefore first and foremost directed towards deterring aggression and 

preserving peace. Our goal is to convince adversaries they have nothing to gain and 

everything to lose from the use of nuclear weapons.

In no way does this approach lower the nuclear threshold. Rather, by convincing 

adversaries that even limited use of nuclear weapons will be more costly than they 

can tolerate, it in fact raises that threshold.

To this end, this review confirms the findings of previous NPRs that the nuclear

triad—supported by North Atlantic Treaty Organization (NATO) dual-capable 

aircraft and a robust nuclear command, control, and communications system—is the 

most cost-effective and strategically sound means of ensuring nuclear deterrence. The 

triad provides the President flexibility while guarding against technological surprise 

orsudden changesin the geopolitical environment. To remain effective, however,we 

must recapitalize our Cold War legacy nuclear forces. 

By the time we complete the necessary modernization of these forces, they will have 

served decades beyond their initial life expectancy. This review affirms the 

modernization programs initiated during the previous Administration to replace our 

nuclear ballistic missile submarines, strategic bombers, nuclear air-launched cruise

missiles, ICBMs, and associated nuclear command and control. Modernizing our 

dual-capable fighter bombers with next-generation F-35 fighter aircraft will maintain 

the strength of NATO’s deterrence posture and maintain our ability to forward 

deploy nuclear weapons, should the security situation demand it.

Recapitalizing the nuclear weapons complex of laboratories and plants is also long 

past due; it is vital we ensure the capability to design, produce, assess, and maintain 

these weapons for as long as they are required. Due to consistent underfunding, 

significant and sustained investments will be required over the coming decade to 

ensure that National Nuclear Security Administration will be able to deliver the 
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nuclear weapons at the needed rate to support the nuclear deterrent into the 2030s 

and beyond.

Maintaining an effective nuclear deterrent is much less expensive than fighting a war

that we were unable to deter. Maintenance costs for today’s nuclear deterrent are 

approximately three percent of the annual defense budget. Additional funding of 

another three to four percent, over more than a decade, will be required to replace 

these aging systems. This is a top priority of the Department of Defense. We are 

mindful of the sustained financial commitment and gratefully recognize the ongoing 

support of the American people and the United States Congress for this important

mission.

While we will be relentless in ensuring our nuclear capabilities are effective, the

United States is not turning away from its long-held arms control, non-proliferation, 

and nuclear security objectives. Our commitment to the goals of the Treaty on the 

Non-Proliferation of Nuclear Weapons (NPT) remains strong. Yet we must 

recognize that the current environment makes further progress toward nuclear arms 

reductions in the near term extremely challenging. Ensuring our nuclear deterrent 

remains strong will provide the best opportunity for convincing other nuclear powers 

to engage in meaningful arms control initiatives.

This review rests on a bedrock truth: nuclear weapons have and will continue to play 

a critical role in deterring nuclear attack and in preventing large-scale conventional 

warfare between nuclear-armed states for the foreseeable future. U.S. nuclear

weapons not only defend our allies against conventional and nuclear threats, they also 

help them avoid the need to develop their own nuclear arsenals. This, in turn, 

furthers global security.

I would be remiss if I did not acknowledge the vital role our Soldiers, Sailors, Airmen, 

Marines, Coast Guardsmen, and civilians play in maintaining a safe, secure, and ready 

nuclear force. Without their ceaseless and often unheralded efforts, America would 

not possess a nuclear deterrent. At the end of the day, deterrence comes down to the 

men and women in uniform – in silos, in the air, and beneath the sea.

To each and every one of them, I wish to express my personal respect and that of a 

grateful and safe Nation.
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Executive Summary

Introduction

On January 27, 2017, President Donald Trump directed Secretary of Defense James 

Mattis to initiate a new Nuclear Posture Review (NPR). The President made clear that 

his first priority is to protect the United States, allies, and partners. He also emphasized 

both the long-term goal of eliminating nuclear weapons and the requirement that the 

United States have modern, flexible, and resilient nuclear capabilities that are safe and 

secure until such a time as nuclear weapons can prudently be eliminated from the world.

The United States remains committed to its efforts in support of the ultimate global 

elimination of nuclear, biological, and chemical weapons. It has reduced the nuclear 

stockpile by over 85 percent since the height of the Cold War and deployed no new 

nuclear capabilities for over two decades. Nevertheless, global threat conditions have 

worsened markedly since the most recent 2010 NPR, including increasingly explicit 

nuclear threats from potential adversaries. The United States now faces a more diverse 

and advanced nuclear-threat environment than ever before, with considerable dynamism 

in potential adversaries’ development and deployment programs for nuclear weapons 

and delivery systems.

An Evolving and Uncertain 

International Security Environment

While the United States has continued to reduce the number and salience of nuclear 

weapons, others, including Russia and China, have moved in the opposite direction. 

They have added new types of nuclear capabilities to their arsenals, increased the salience 

of nuclear forces in their strategies and plans, and engaged in increasingly aggressive 

behavior, including in outer space and cyber space. North Korea continues its illicit 

pursuit of nuclear weapons and missile capabilities in direct violation of United Nations 

(U.N.) Security Council resolutions. Iran has agreed to constraints on its nuclear 

program in the Joint Comprehensive Plan of Action (JCPOA). Nevertheless, it retains 

the technological capability and much of the capacity necessary to develop a nuclear 

weapon within one year of a decision to do so. 

There now exists an unprecedented range and mix of threats, including major 

conventional, chemical, biological, nuclear, space, and cyber threats, and violent nonstate actors. These developments have produced increased uncertainty and risk.
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This rapid deterioration of the threat environment since the 2010 NPR must now shape 

our thinking as we formulate policy and strategy, and initiate the sustainment and 

replacement of U.S. nuclear forces. This 2018 NPR assesses previous nuclear policies 

and requirements that were established amid a more benign nuclear environment and 

more amicable Great Power relations. It focuses on identifying the nuclear policies, 

strategy, and corresponding capabilities needed to protect America in the deteriorating 

threat environment that confronts the United States, allies, and partners. It is strategy 

driven and provides guidance for the nuclear force posture and policy requirements 

needed now and in the future.

The United States does not wish to regard either Russia or China as an adversary and 

seeks stable relations with both. We have long sought a dialogue with China to enhance 

our understanding of our respective nuclear policies, doctrine, and capabilities; to 

improve transparency; and to help manage the risks of miscalculation and misperception. 

We hope that China will share this interest and that meaningful dialogue can commence. 

The United States and Russia have in the past maintained strategic dialogues to manage 

nuclear competition and nuclear risks. Given Russian actions, including its occupation 

of Crimea, this constructive engagement has declined substantially. We look forward 

to conditions that would once again allow for transparent and constructive engagement 

with Russia. 

Nevertheless, this review candidly addresses the challenges posed by Russian, Chinese, 

and other states’ strategic policies, programs, and capabilities, particularly nuclear. It 

presents the flexible, adaptable, and resilient U.S. nuclear capabilities now required to 

protect the United States, allies, and partners, and promote strategic stability.

The Value of U.S. Nuclear Capabilities

The fundamental reasons why U.S. nuclear capabilities and deterrence strategies are 

necessary for U.S., allied, and partner security are readily apparent. U.S. nuclear 

capabilities make essential contributions to the deterrence of nuclear and non-nuclear 

aggression. The deterrence effects they provide are unique and essential to preventing 

adversary nuclear attacks, which is the highest priority of the United States.

U.S. nuclear capabilities cannot prevent all conflict, and should not be expected to do 

so. But, they contribute uniquely to the deterrence of both nuclear and non-nuclear 

aggression. They are essential for these purposes and will be so for the foreseeable 

future. Non-nuclear forces also play essential deterrence roles, but do not provide 

comparable deterrence effects--as is reflected by past, periodic, and catastrophic failures 

of conventional deterrence to prevent Great Power war before the advent of nuclear 

deterrence. In addition, conventional forces alone are inadequate to assure many allies 
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who rightly place enormous value on U.S. extended nuclear deterrence for their

security, which correspondingly is also key to non-proliferation.

U.S. Nuclear Capabilities and 

Enduring National Objectives

The highest U.S. nuclear policy and strategy priority is to deter potential adversaries 

from nuclear attack of any scale. However, deterring nuclear attack is not the sole 

purpose of nuclear weapons. Given the diverse threats and profound uncertainties of 

the current and future threat environment, U.S. nuclear forces play the following 

critical roles in U.S. national security strategy. They contribute to the:

› Deterrence of nuclear and non-nuclear attack;

› Assurance of allies and partners;

› Achievement of U.S. objectives if deterrence fails; and

› Capacity to hedge against an uncertain future.

These roles are complementary and interrelated, and the adequacy of U.S. nuclear forces 

must be assessed against each role and the strategy designed to fulfill it. Preventing 

proliferation and denying terrorists access to finished weapons, material, or expertise 

are also key considerations in the elaboration of U.S. nuclear policy and requirements. 

These multiple roles and objectives constitute the guiding pillars for U.S. nuclear policy 

and requirements.

Deterrence of Nuclear and Non-Nuclear Attack

Effective U.S. deterrence of nuclear attack and non-nuclear strategic attack requires 

ensuring that potential adversaries do not miscalculate regarding the consequences of 

nuclear first use, either regionally or against the United States itself. They must 

understand that there are no possible benefits from non-nuclear aggression or limited 

nuclear escalation. Correcting any such misperceptions is now critical to maintaining 

strategic stability in Europe and Asia.

Potential adversaries must recognize that across the emerging range of threats and 

contexts: 1) the United States is able to identify them and hold them accountable for 

acts of aggression, including new forms of aggression; 2) we will defeat non-nuclear 

strategic attacks; and, 3) any nuclear escalation will fail to achieve their objectives, and 

will instead result in unacceptable consequences for them.

There is no “one size fits all” for deterrence. Consequently, the United States will apply 

a tailored and flexible approach to effectively deter across a spectrum of adversaries, 
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threats, and contexts. Tailored deterrence strategies communicate to different potential 

adversaries that their aggression would carry unacceptable risks and intolerable costs 

according to their particular calculations of risk and cost.

U.S. nuclear capabilities, and nuclear command, control, and communications (NC3), 

must be increasingly flexible to tailor deterrence strategies across a range of potential 

adversaries and threats, and enable adjustments over time. Accordingly, the United 

States will maintain the range of flexible nuclear capabilities needed to ensure that 

nuclear or non-nuclear aggression against the United States, allies, and partners will fail 

to achieve its objectives and carry with it the credible risk of intolerable consequences 

for potential adversaries now and in the future.

To do so, the United States will sustain and replace its nuclear capabilities, modernize 

NC3, and strengthen the integration of nuclear and non-nuclear military planning. 

Combatant Commands and Service components will be organized and resourced for this 

mission, and will plan, train, and exercise to integrate U.S. nuclear and non-nuclear 

forces to operate in the face of adversary nuclear threats and employment. The United 

States will coordinate integration activities with allies facing nuclear threats and examine 

opportunities for additional allied burden sharing of the nuclear deterrence mission.

Assurance of Allies and Partners

The United States has formal extended deterrence commitments that assure European, 

Asian, and Pacific allies. Assurance is a common goal based on collaboration with allies 

and partners to deter or defeat the threats we face. No country should doubt the 

strength of our extended deterrence commitments or the strength of U.S. and allied 

capabilities to deter, and if necessary defeat, any potential adversary’s nuclear or nonnuclear aggression. In many cases, effectively assuring allies and partners depends on 

their confidence in the credibility of U.S. extended nuclear deterrence, which enables 

most to eschew possession of nuclear weapons, thereby contributing to U.S. nonproliferation goals.

Achieve U.S. Objectives Should Deterrence Fail

The United States would only consider the employment of nuclear weapons in extreme 

circumstances to defend the vital interests of the United States, its allies, and partners. 

Nevertheless, if deterrence fails, the United States will strive to end any conflict at the 

lowest level of damage possible and on the best achievable terms for the United States, 

allies, and partners. U.S. nuclear policy for decades has consistently included this 

objective of limiting damage if deterrence fails.
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Hedge against an Uncertain Future 

The United States will continue efforts to create a more cooperative and benign security 

environment, but must also hedge against prospective and unanticipated risks. Hedging 

strategies help reduce risk and avoid threats that otherwise may emerge over time, 

including geopolitical, technological, operational, and programmatic. They also 

contribute to deterrence and can help reduce potential adversaries’ confidence that they 

can gain advantage through a “break out” or expansion of nuclear capabilities. Given the 

increasing prominence of nuclear weapons in potential adversaries’ defense policies and 

strategies, and the uncertainties of the future threat environment, U.S. nuclear 

capabilities and the ability to quickly modify those capabilities can be essential to mitigate 

or overcome risk, including the unexpected.

U.S. Nuclear Enterprise Personnel

Effective deterrence would be impossible without the thousands of members of the 

United States Armed Forces and civilian personnel who dedicate their professional lives 

to the deterrence of war and protecting the Nation. These exceptional men and women 

are held to the most rigorous standards and make the most vital contribution to U.S. 

nuclear capabilities and deterrence.

The Service members and civilians involved in the nuclear deterrence mission do so with 

little public recognition or fanfare. Theirs is an unsung duty of the utmost importance. 

They deserve the support of the American people for the safety, security, and stability 

they provide the Nation, and indeed the world. The Service reforms we have 

accordingly implemented were long overdue, and the Department of Defense remains 

fully committed to properly supporting the Service members who protect the United 

States against nuclear threats.

The Triad: Present and Future

Today’s strategic nuclear triad, largely deployed in the 1980s or earlier, consists of: 

submarines (SSBNs) armed with submarine-launched ballistic missiles (SLBM); landbased intercontinental ballistic missiles (ICBM); and strategic bombers carrying gravity 

bombs and air-launched cruise missiles (ALCMs). The triad and non-strategic nuclear 

forces, with supporting NC3, provides diversity and flexibility as needed to tailor U.S. 

strategies for deterrence, assurance, achieving objectives should deterrence fail, and 

hedging.
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The increasing need for this diversity and flexibility, in turn, is one of the primary 

reasons why sustaining and replacing the nuclear triad and non-strategic nuclear 

capabilities, and modernizing NC3, is necessary now. The triad’s synergy and 

overlapping attributes help ensure the enduring survivability of our deterrence 

capabilities against attack and our capacity to hold at risk a range of adversary targets 

throughout a crisis or conflict. Eliminating any leg of the triad would greatly ease 

adversary attack planning and allow an adversary to concentrate resources and attention 

on defeating the remaining two legs. Therefore, we will sustain our legacy triad systems 

until the planned replacement programs are deployed.

The United States currently operates 14 OHIO-class SSBNs and will continue to take 

the steps needed to ensure that OHIO SSBNs remain operationally effective and 

survivable until replaced by the COLUMBIA-class SSBN. The COLUMBIA program 

will deliver a minimum of 12 SSBNs to replace the current OHIO fleet and is designed 

to provide required deterrence capabilities for decades.

The ICBM force consists of 400 single-warhead Minuteman III missiles deployed in 

underground silos and dispersed across several states. The United States has initiated 

the Ground-Based Strategic Deterrent (GBSD) program to begin the replacement of 

Minuteman III in 2029. The GBSD program will also modernize the 450 ICBM launch 

facilities that will support the fielding of 400 ICBMs.

The bomber leg of the triad consists of 46 nuclear-capable B-52H and 20 nuclear-capable 

B-2A “stealth” strategic bombers. The United States has initiated a program to develop 

and deploy the next-generation bomber, the B-21 Raider. It will first supplement, and 

eventually replace elements of the conventional and nuclear-capable bomber force 

beginning in the mid-2020s.

The B83-1 and B61-11 gravity bombs can hold at risk a variety of protected targets. As 

a result, both will be retained in the stockpile, at least until there is sufficient confidence 

in the B61-12 gravity bomb that will be available in 2020. 

Beginning in 1982, B-52H bombers were equipped with ALCMs. Armed with ALCMs, 

the B-52H can stay outside adversary air defenses and remain effective. The ALCM, 

however, is now more than 25 years past its design life and faces continuously improving 

adversary air defense systems. The Long-Range Stand-Off (LRSO) cruise missile 

replacement program will maintain into the future the bomber force capability to deliver 

stand-off weapons that can penetrate and survive advanced integrated air defense 

systems, thus supporting the long-term effectiveness of the bomber leg.

The current non-strategic nuclear force consists exclusively of a relatively small number 

of B61 gravity bombs carried by F-15E and allied dual capable aircraft (DCA). The 

United States is incorporating nuclear capability onto the forward-deployable, nuclearcapable F-35 as a replacement for the current aging DCA. In conjunction with the 
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ongoing life extension program for the B61 bomb, it will be a key contributor to 

continued regional deterrence stability and the assurance of allies.

Flexible and Secure Nuclear Capabilities: 

An Affordable Priority

Throughout past decades, senior U.S. officials have emphasized that the highest priority 

of the Department of Defense is deterring nuclear attack and maintaining the nuclear 

capabilities necessary to do so. While cost estimates for the program to sustain and 

replace U.S. nuclear capabilities vary, even the highest of these projections place the 

highpoint of the future cost at approximately 6.4 percent of the current DoD budget. 

Maintaining and operating our current aging nuclear forces now requires between two 

and three percent of the DoD budget. The replacement program to rebuild the triad 

for decades of service will peak for several years at only approximately four percent 

beyond the ongoing two to three percent needed for maintenance and operations. This 

6.4 percent of the current DoD budget required for the long-term replacement program 

represents less than one percent of the overall federal budget. This level of spending to 

replace U.S. nuclear capabilities compares favorably to the 10.6 percent of the DoD 

budget required during the last such investment period in the 1980s, which at the time 

was almost 3.7 percent of the federal budget, and the 17.1 percent of the DoD budget 

required in the early 1960s.

Given the criticality of effective U.S. nuclear deterrence to the safety of the American 

people, allies and partners there is no doubt that the sustainment and replacement 

program should be regarded as both necessary and affordable.

Enhancing Deterrence with Non-strategic Nuclear 

Capabilities

Existing elements of the nuclear force replacement program predate the dramatic 

deterioration of the strategic environment. To meet the emerging requirements of U.S. 

strategy, the United States will now pursue select supplements to the replacement 

program to enhance the flexibility and responsiveness of U.S. nuclear forces. It is a 

reflection of the versatility and flexibility of the U.S. triad that only modest supplements 

are now required in this much more challenging threat environment.

These supplements will enhance deterrence by denying potential adversaries any 

mistaken confidence that limited nuclear employment can provide a useful advantage 

over the United States and its allies. Russia’s belief that limited nuclear first use, 

potentially including low-yield weapons, can provide such an advantage is based, in part, 

on Moscow’s perception that its greater number and variety of non-strategic nuclear 
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systems provide a coercive advantage in crises and at lower levels of conflict. Recent 

Russian statements on this evolving nuclear weapons doctrine appear to lower the 

threshold for Moscow’s first-use of nuclear weapons. Russia demonstrates its 

perception of the advantage these systems provide through numerous exercises and 

statements. Correcting this mistaken Russian perception is a strategic imperative.

To address these types of challenges and preserve deterrence stability, the United States 

will enhance the flexibility and range of its tailored deterrence options. To be clear, this 

is not intended to, nor does it enable, “nuclear war-fighting.” Expanding flexible U.S. 

nuclear options now, to include low-yield options, is important for the preservation of 

credible deterrence against regional aggression. It will raise the nuclear threshold and 

help ensure that potential adversaries perceive no possible advantage in limited nuclear 

escalation, making nuclear employment less likely.

Consequently, the United States will maintain, and enhance as necessary, the capability 

to forward deploy nuclear bombers and DCA around the world. We are committed to 

upgrading DCA with the nuclear-capable F-35 aircraft. We will work with NATO to 

best ensure—and improve where needed—the readiness, survivability, and operational 

effectiveness of DCA based in Europe. 

Additionally, in the near-term, the United States will modify a small number of existing 

SLBM warheads to provide a low-yield option, and in the longer term, pursue a modern 

nuclear-armed sea-launched cruise missile (SLCM). Unlike DCA, a low-yield SLBM 

warhead and SLCM will not require or rely on host nation support to provide deterrent 

effect. They will provide additional diversity in platforms, range, and survivability, and 

a valuable hedge against future nuclear “break out” scenarios. 

DoD and National Nuclear Security Administration (NNSA) will develop for 

deployment a low-yield SLBM warhead to ensure a prompt response option that is able 

to penetrate adversary defenses. This is a comparatively low-cost and near term 

modification to an existing capability that will help counter any mistaken perception of 

an exploitable “gap” in U.S. regional deterrence capabilities. 

In addition to this near-term step, for the longer term the United States will pursue a 

nuclear-armed SLCM, leveraging existing technologies to help ensure its cost 

effectiveness. SLCM will provide a needed non-strategic regional presence, an assured 

response capability. It also will provide an arms control compliant response to Russia’s 

non-compliance with the Intermediate-range Nuclear Forces Treaty, its non-strategic 

nuclear arsenal, and its other destabilizing behaviors. 

In the 2010 NPR, the United States announced the retirement of its previous nucleararmed SLCM, which for decades had contributed to deterrence and the assurance of 

allies, particularly in Asia. We will immediately begin efforts to restore this capability 
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by initiating a capability study leading to an Analysis of Alternatives (AoA) for the rapid 

development of a modern SLCM. 

These supplements to the planned nuclear force replacement program are prudent 

options for enhancing the flexibility and diversity of U.S. nuclear capabilities. They are 

compliant with all treaties and agreements, and together, they will: provide a diverse 

set of characteristics enhancing our ability to tailor deterrence and assurance; expand the 

range of credible U.S. options for responding to nuclear or non-nuclear strategic attack; 

and, enhance deterrence by signaling to potential adversaries that their limited nuclear 

escalation offers no exploitable advantage. 

Nuclear Command, Control, and Communications 

Modernization

The United States must have an NC3 system that provides control of U.S. nuclear forces 

at all times, even under the enormous stress of a nuclear attack. NC3 capabilities must 

assure the integrity of transmitted information and possess the resiliency and 

survivability necessary to reliably overcome the effects of nuclear attack. During 

peacetime and crisis, the NC3 system performs five crucial functions: detection, 

warning, and attack characterization; adaptive nuclear planning; decision-making 

conferencing; receiving Presidential orders; and enabling the management and direction 

of forces.

Today’s NC3 system is a legacy of the Cold War, last comprehensively updated almost 

three decades ago. It includes interconnected elements composed of warning satellites 

and radars; communications satellites, aircraft, and ground stations; fixed and mobile

command posts; and the control centers for nuclear systems.

While once state-of-the-art, the NC3 system is now subject to challenges from both 

aging system components and new, growing 21st century threats. Of particular concern 

are expanding threats in space and cyber space, adversary strategies of limited nuclear 

escalation, and the broad diffusion within DoD of authority and responsibility for 

governance of the NC3 system, a function which, by its nature, must be integrated.

In light of the critical need to ensure our NC3 system remains survivable and effective, 

the United States will pursue a series of initiatives. This includes: strengthening 

protection against cyber threats, strengthening protection against space-based threats, 

enhancing integrated tactical warning and attack assessment, improving command post 

and communication links, advancing decision support technology, integrating planning 

and operations, and reforming governance of the overall NC3 system.
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Nuclear Weapons Infrastructure

An effective, responsive, and resilient nuclear weapons infrastructure is essential to the 

U.S. capacity to adapt flexibly to shifting requirements. Such an infrastructure offers 

tangible evidence to both allies and potential adversaries of U.S. nuclear weapons 

capabilities and thus contributes to deterrence, assurance, and hedging against adverse 

developments. It also discourages adversary interest in arms competition.

DoD generates military requirements for the nuclear warheads to be carried on delivery 

platforms. NNSA oversees the research, development, test, assessment, and production 

programs that respond to DoD warhead requirements.

Over the past several decades, the U.S. nuclear weapons infrastructure has suffered the 

effects of age and underfunding. Over half of NNSA’s infrastructure is over 40 years 

old, and a quarter dates back to the Manhattan Project era. All previous NPRs 

highlighted the need to maintain a modern nuclear weapons infrastructure, but the 

United States has fallen short in sustaining a modern infrastructure that is resilient and 

has the capacity to respond to unforeseen developments. There now is no margin for 

further delay in recapitalizing the physical infrastructure needed to produce strategic 

materials and components for U.S. nuclear weapons. Just as our nuclear forces are an 

affordable priority, so is a resilient and effective nuclear weapons infrastructure, without 

which our nuclear deterrent cannot exist.

The U.S. must have the ability to maintain and certify a safe, secure, and effective nuclear 

arsenal. Synchronized with DoD replacement programs, the United States will sustain 

and deliver on-time the warheads needed to support both strategic and non-strategic 

nuclear capabilities by:

› Completing the W76-1 Life Extension Program (LEP) by Fiscal Year (FY) 2019;

› Completing the B61-12 LEP by FY2024;

› Completing the W88 alterations by FY2024;

› Synchronizing NNSA’s W80-4 life extension, with DoD’s LRSO program and 

completing the W80-4 LEP by FY2031;

› Advancing the W78 warhead replacement one year to FY19 to support fielding on 

GBSD by 2030 and investigate the feasibility of fielding the nuclear explosive 

package in a Navy flight vehicle; 

› Sustaining the B83-1 past its currently planned retirement date until a suitable 

replacement is identified; and,
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NUCLEAR POSTURE REVIEW

› Exploring future ballistic missile warhead requirements based on the threats and 

vulnerabilities of potential adversaries, including the possibility of common 

reentry systems between Air Force and Navy systems.

The United States will pursue initiatives to ensure the necessary capability, capacity, and 

responsiveness of the nuclear weapons infrastructure and the needed skills of the 

workforce, including the following:

› Pursue a joint DoD and Department of Energy advanced technology development

capability to ensure that efforts are appropriately integrated to meet DoD needs.

› Provide the enduring capability and capacity to produce plutonium pits at a rate of 

no fewer than 80 pits per year by 2030. A delay in this would result in the need 

for a higher rate of pit production at higher cost.

› Ensure that current plans to reconstitute the U.S. capability to produce lithium 

compounds are sufficient to meet military requirements.

› Fully fund the Uranium Processing Facility and ensure availability of sufficient low 

enriched uranium to meet military requirements.

› Ensure the necessary reactor capacity to produce an adequate supply of tritium to 

meet military requirements.

› Ensure continuity in the U.S. capability to develop and manufacture secure, 

trusted strategic radiation-hardened microelectronic systems beyond 2025 to 

support stockpile modernization.

› Rapidly pursue the Stockpile Responsiveness Program established by Congress to 

expand opportunities for young scientists and engineers to advance warhead 

design, development, and production skills.

› Develop an NNSA roadmap that sizes production capacity to modernization and 

hedging requirements.

› Retain confidence in nuclear gravity bombs needed to meet deterrence needs.

› Maintain and enhance the computational, experimental, and testing capabilities 

needed to annually assess nuclear weapons.

Countering Nuclear Terrorism

The U.S. strategy to combat nuclear terrorism encompasses a wide range of activities 

that comprise a defense-in-depth against current and emerging dangers. Under this 

multilayered approach, the United States strives to prevent terrorists from obtaining 

nuclear weapons or weapons-usable materials, technology, and expertise; counter their 

efforts to acquire, transfer, or employ these assets; and respond to nuclear incidents, by 
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NUCLEAR POSTURE REVIEW

locating and disabling a nuclear device or managing the consequences of a nuclear 

detonation.

For effective deterrence, the United States will hold fully accountable any state, terrorist 

group, or other non-state actor that supports or enables terrorist efforts to obtain or 

employ nuclear devices. Although the role of U.S. nuclear weapons in countering 

nuclear terrorism is limited, our adversaries must understand that a terrorist nuclear 

attack against the United States or its allies and partners would qualify as an “extreme 

circumstance” under which the United States could consider the ultimate form of 

retaliation.

Non-proliferation and Arms Control

Effective nuclear non-proliferation and arms control measures can support U.S., allied, 

and partner security by controlling the spread of nuclear materials and technology; 

placing limits on the production, stockpiling and deployment of nuclear weapons; 

decreasing misperception and miscalculation; and avoiding destabilizing nuclear arms 

competition. The United States will continue its efforts to: 1) minimize the number of 

nuclear weapons states, including by maintaining credible U.S. extended nuclear 

deterrence and assurance; 2) deny terrorist organizations access to nuclear weapons and 

materials; 3) strictly control weapons-usable material, related technology, and 

expertise; and 4) seek arms control agreements that enhance security, and are verifiable 

and enforceable.

The Nuclear Non-Proliferation Treaty (NPT) is a cornerstone of the nuclear nonproliferation regime. It plays a positive role in building consensus for non-proliferation 

and enhances international efforts to impose costs on those that would pursue nuclear 

weapons outside the Treaty.

However, nuclear non-proliferation today faces acute challenges. Most significantly, 

North Korea is pursuing a nuclear path in direct contravention of the NPT and in direct 

opposition to numerous U.N. Security Council resolutions. Beyond North Korea looms 

the challenge of Iran. Although the JCPOA may constrain Tehran’s nuclear weapons 

program, there is little doubt Iran could achieve a nuclear weapon capability rapidly if it 

decides to do so.

In continuing support of nuclear non-proliferation, the United States will work to 

increase transparency and predictability, where appropriate, to avoid potential 

miscalculation among nuclear weapons states and other possessor states through 

strategic dialogues, risk-reduction communications channels, and the sharing of best 

practices related to nuclear weapons safety and security.
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NUCLEAR POSTURE REVIEW

Although the United States will not seek ratification of the Comprehensive Nuclear Test 

Ban Treaty, it will continue to support the Comprehensive Nuclear Test Ban Treaty 

Organization Preparatory Committee as well as the International Monitoring System 

and the International Data Center. The United States will not resume nuclear explosive 

testing unless necessary to ensure the safety and effectiveness of the U.S. nuclear arsenal, 

and calls on all states possessing nuclear weapons to declare or maintain a moratorium 

on nuclear testing.

Arms control can contribute to U.S. security by helping to manage strategic competition 

among states. It can foster transparency, understanding, and predictability in adversary 

relations, thereby reducing the risk of misunderstanding and miscalculation.

The United States is committed to arms control efforts that advance U.S., allied, and 

partner security; are verifiable and enforceable; and include partners that comply 

responsibly with their obligations. Such arms control efforts can contribute to the U.S. 

capability to sustain strategic stability. Further progress is difficult to envision, however, 

in an environment that is characterized by continuing significant non-compliance with 

existing arms control obligations and commitments, and by potential adversaries who 

seek to change borders and overturn existing norms.

In this regard, Russia continues to violate a series of arms control treaties and 

commitments. In the nuclear context, the most significant Russian violation involves a 

system banned by the Intermediate-range Nuclear Forces Treaty. In a broader context, 

Russia is either rejecting or avoiding its obligations and commitments under numerous 

agreements, and has rebuffed U.S. efforts to follow the New Strategic Arms Reduction 

Treaty (START) with another round of negotiated reductions and to pursue reductions 

in non-strategic nuclear forces.

Nevertheless, New START is in effect through February 2021, and with mutual 

agreement may be extended for up to five years, to 2026. The United States already has 

met the Treaty’s central limits which go into force on February 5, 2018, and will 

continue to implement the New START Treaty.

The United States remains willing to engage in a prudent arms control agenda. We are 

prepared to consider arms control opportunities that return parties to compliance, 

predictability, and transparency, and remain receptive to future arms control 

negotiations if conditions permit and the potential outcome improves the security of the 

United States, its allies, and partners.

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NUCLEAR POSTURE REVIEW

I. Introduction TO U.S. 

NUCLEAR POLICY AND STRATEGY

“The Secretary shall initiate a new Nuclear Posture Review 

to ensure that the United States nuclear deterrent is modern, 

robust, flexible, resilient, ready and appropriately tailored 

to deter 21st-century threats and reassure our allies.”

 President Donald Trump, 2017
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NUCLEAR POSTURE REVIEW

I. Introduction TO U.S. NUCLEAR POLICY AND STRATEGY

On January 27, 2017, President Donald Trump directed Secretary of Defense James 

Mattis to initiate a new Nuclear Posture Review (NPR). The President made clear that 

his first priority is to protect the United States, allies and partners. He emphasized both 

the long-term goal of eliminating nuclear weapons and the requirement that the United 

States have modern, flexible, 

and resilient nuclear 

capabilities that are safe, 

secure, and effective until such 

a time as nuclear weapons can 

prudently be eliminated from 

the world.

The United States remains 

committed to its efforts in 

support of the ultimate global 

elimination of nuclear, 

biological, and chemical 

weapons. It has negotiated 

multiple arms control treaties 

and has fully abided by its treaty 

commitments. In addition, for 

over two decades the United 

States has deployed no new 

nuclear capabilities, advanced nuclear reduction and non-proliferation initiatives to 

Russia and others, and strengthened alliance commitments and capabilities to safeguard 

international order and prevent further proliferation of nuclear weapons.

Nevertheless, global threat conditions have worsened markedly since the most recent, 

2010 NPR. There now exist an unprecedented range and mix of threats, including major 

conventional, chemical, biological, nuclear, space, and cyber threats, and violent nonstate actors. International relations are volatile. Russia and China are contesting the 

international norms and order we have worked with our allies, partners, and members 

of the international community to build and sustain. Some regions are marked by 

persistent disorder that appears likely to continue and possibly intensify. These 

developments have produced increased uncertainty and risk, demanding a renewed 

seriousness of purpose in deterring threats and assuring allies and partners.

While the United States has continued to reduce the number and salience of nuclear 

weapons, others, including Russia and China, have moved in the opposite direction. 

Russia has expanded and improved its strategic and non-strategic nuclear forces. China’s 

military modernization has resulted in an expanded nuclear force, with little to no 

transparency into its intentions. North Korea continues its illicit pursuit of nuclear 

The Ohio-class ballistic missile submarine USS Nebraska (SSBN 739) 

transits into open ocean during an underway for training and 

proficiency. Nebraska is one of eight ballistic missile submarines 

stationed at Naval Base Kitsap-Bangor and recently completed an 

extended major maintenance period, including an engineered 

refueling overhaul, at Puget Sound Naval Shipyard and Intermediate 

Maintenance Facility. (U.S. Navy photo)
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NUCLEAR POSTURE REVIEW

weapons and missile capabilities in direct violation of United Nations (U.N.) Security 

Council resolutions. Russia and North Korea have increased the salience of nuclear 

forces in their strategies and plans and have engaged in increasingly explicit nuclear 

threats. Along with China, they have also engaged in increasingly aggressive behavior in 

outer space and cyber space.

As a result, the 2018 NPR assesses recent nuclear policies and requirements that were 

established amid a more benign nuclear environment and more amicable Great Power 

relations. It focuses on identifying the nuclear policies, strategy, and corresponding 

capabilities needed to protect America, its allies, and partners in a deteriorating threat 

environment. It is strategy driven and provides guidance for the nuclear force structure 

and policy requirements needed now and in the future to maintain peace and stability in 

a rapidly shifting environment with significant future uncertainty.

The current threat environment and future uncertainties now necessitate a national 

commitment to maintain modern and effective nuclear forces, as well as the 

infrastructure needed to support them. Consequently, the United States has initiated a 

series of programs to sustain and replace existing nuclear capabilities before they reach 

the end of their service lives. These programs are critical to preserving our ability to 

deter threats to the Nation.
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NUCLEAR POSTURE REVIEW

II. An Evolving and Uncertain 

International Security Environment

“For the first time in 25 years, the United States is facing a 

return to great power competition. Russia and China both have 

advanced their military capabilities to act as global 

powers...Others are now pursuing advanced technology, 

including military technologies that were once the exclusive 

province of great powers – this trend will only continue.”

Admiral Richardson, Chief of Naval Operations

“A Design for Maintaining Maritime Superiority,” 2017
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NUCLEAR POSTURE REVIEW

II. An Evolving and Uncertain International Security Environment

Each previous NPR emphasized that changes in the international security environment 

shape U.S. nuclear policy, strategy, and posture. The U.S. Joint Chiefs of Staff recently 

assessed that the emerging security environment, “can be described by simultaneous and 

connected challenges—contested norms and persistent disorder.” The rapid deterioration 

of the threat environment since the 2010 NPR must now shape our thinking as we 

formulate policy and strategy, while we sustain and replace U.S. nuclear capabilities. 

The last NPR was based on a number of key findings and expectations regarding the nature 

of the security environment that have not since been realized. Most notably, it reflected 

the expectations that:

› The prospects for military confrontation with Russia, or among Great Powers, had 

declined and would continue to decline dramatically.

› The United States could decrease incentives for nuclear proliferation globally and 

reduce the likelihood of nuclear weapons employment by reducing both the role of 

nuclear weapons in U.S. national security strategy and the number of nuclear 

weapons in the U.S. arsenal. This was based in part on the aspiration that if the 

United States took the lead in reducing nuclear arms, other nuclear-armed states 

would follow.

U.S. efforts to reduce the roles and numbers of nuclear weapons, and convince other states 

to do the same, have included reducing the U.S. nuclear stockpile by over 85 percent since 

its Cold War high. Potential adversaries, however, have expanded and modernized their 

nuclear forces. This and additional negative developments in the international security 

environment presents new and serious challenges to U.S., allied and partner security. They 

have rendered our earlier, sanguine findings and expectations an outdated basis for U.S. 

nuclear policy, strategy, and posture going forward.

The Return of Great Power Competition

Since 2010 we have seen the return of Great Power competition. To varying degrees, 

Russia and China have made clear they seek to substantially revise the post-Cold War 

international order and norms of behavior. Russia has demonstrated its willingness to use 

force to alter the map of Europe and impose its will on its neighbors, backed by implicit 

and explicit nuclear first-use threats. Russia is in violation of its international legal and 

political commitments that directly affect the security of others, including the 1987 

Intermediate-Range Nuclear Forces (INF) Treaty, the 2002 Open Skies Treaty, and the 

1991 Presidential Nuclear Initiatives. Its occupation of Crimea and direct support for 

Russia-led forces in Eastern Ukraine violate its commitment to respect the territorial 

integrity of Ukraine that they made in the 1994 Budapest Memorandum. China meanwhile 

has rejected the ruling of the Permanent Court of Arbitration Tribunal that found China’s 

maritime claims in the South China Sea to be without merit and some of its related activities 

illegal under the U.N. Convention on the Law of the Sea and customary international law. 
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NUCLEAR POSTURE REVIEW

Subsequently, China has continued to undertake assertive military initiatives to create “facts 

on the ground” in support of its territorial claims over features in the East and South China 

Seas.

Russia and China are pursuing asymmetric ways and means to counter U.S. conventional 

capabilities, thereby increasing the risk of miscalculation and the potential for military 

confrontation with the United States, its allies, and partners. Both countries are developing 

counter-space military capabilities to deny the United States the ability to conduct spacebased intelligence, surveillance, and reconnaissance (ISR); nuclear command, control, and 

communications (NC3); and positioning, navigation, and timing. Both seek to develop 

offensive cyberspace capabilities to deter, disrupt, or defeat U.S. forces dependent on 

computer networks. Both are fielding an array of anti-access area denial (A2/AD) 

capabilities and underground facilities to counter U.S. precision conventional strike 

capabilities and to raise the cost for the United States to reinforce its European and Asian 

allies and partners. While nuclear weapons play a deterrent role in both Russian and 

Chinese strategy, Russia may also rely on threats of limited nuclear first use, or actual first 

use, to coerce us, our allies, and partners into terminating a conflict on terms favorable to 

Russia. Moscow apparently believes that the United States is unwilling to respond to 

Russian employment of tactical nuclear weapons with strategic nuclear weapons.

The United States does not wish to regard either Russia or China as an adversary and seeks 

stable relations with both. We continue to seek a dialogue with China to enhance our 

understanding of our respective nuclear policies, doctrine, and capabilities; to improve 

transparency; and to help manage the risks of miscalculation and misperception. The 

United States and Russia have in the past maintained strategic dialogues to manage nuclear 

competition and nuclear risks. Given Russian actions, including its occupation of Crimea, 

this constructive engagement has declined substantially. The United States looks forward 

to a new day when Russia engages with the United States, its allies, and partners 

transparently and constructively, without aggressive actions and coercive nuclear threats. 

Nevertheless, this review candidly addresses the challenges posed by Russian, Chinese, and 

other states’ strategic policies, programs, and capabilities, particularly nuclear, and the 

flexible, adaptable, and resilient U.S. nuclear capabilities required to protect the United 

States, allies and partners.

Other Nuclear-Armed States Have Not Followed Our Lead

Despite concerted U.S. efforts to reduce the role of nuclear weapons in international affairs 

and to negotiate reductions in the number of nuclear weapons, since 2010 no potential 

adversary has reduced either the role of nuclear weapons in its national security strategy or 

the number of nuclear weapons it fields. Rather, they have moved decidedly in the opposite 

direction. As a result, there is an increased potential for regional conflicts involving 
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NUCLEAR POSTURE REVIEW

nuclear-armed adversaries in several parts of the world and the potential for adversary 

nuclear escalation in crises or conflict.

Figure 1 illustrates the marked difference between U.S. efforts to reduce the salience of 

nuclear weapons and the contrary actions of others over the past decade.

Russia

Russia considers the United States and the North Atlantic Treaty Organization (NATO) to 

be the principal threats to its contemporary geopolitical ambitions. Russian strategy and 

doctrine emphasize the potential coercive and military uses of nuclear weapons. It 

mistakenly assesses that the threat of nuclear escalation or actual first use of nuclear 

weapons would serve to “de-escalate” a conflict on terms favorable to Russia. These 

mistaken perceptions increase the prospect for dangerous miscalculation and escalation.

RUSSIA CHINA NORTH KOREA UNITED STATES

DEVELOPMENT FIELDED LAND SEA AIR

KEY

PAK-FA DCA

NUCLEAR DELIVERY SYSTEMS SINCE 2010

SSC-08 GLCM

Yasen

SSGN

Status-6 AUV

Kh-102 ALCM

Type 094 

SSBN

Gorae

SSB

SS-27 Mod 2 

ICBM

CSS-4 Mod 2/3 ICBM

CSS-10 Mod 1/2 ICBM CSS-5 Mod 6 MRBM

SCUD C 

SRBM

Musudan

IRBM

ER SCUD

MRBM Hwasong-12 IRBM

SS-N-32 SLBM

DF-26 IRBM

JL-2 SLBM

CSS-X-20 ICBM

Pukguksong-1 SLBM

F-35A

Ground-Launched Sea-Launched Air-Launched

SS-X-28 ICBM

SS-19 Mod-X-4 ICBM

SS-X-29 ICBM

SS-N-30 SLCM

Borei

SSBN

Kh-32 ALCM

PAK-DA Bomber

Nodong

MRBM

Hwasong-14 ICBM

Hwasong-13 ICBM Hwasong-15 ICBM

Pukguksong-2 MRBM

Type 096 

SSBN JL-3 SLBM

Figure 1. Nuclear Delivery Systems Since 2010

Data provided by the DoD
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NUCLEAR POSTURE REVIEW

Russia has sought to enable the implementation of its strategy and doctrine through a 

comprehensive modernization of its nuclear arsenal. Russia’s strategic nuclear 

modernization has increased, and will continue to increase its warhead delivery capacity, 

and provides Russia with the ability to rapidly expand its deployed warhead numbers.

In addition to modernizing “legacy” Soviet nuclear systems, Russia is developing and 

deploying new nuclear warheads and launchers. These efforts include multiple upgrades 

for every leg of the Russian nuclear triad of strategic bombers, sea-based missiles, and landbased missiles. Russia is also developing at least two new intercontinental range systems, 

a hypersonic glide vehicle, and a new intercontinental, nuclear-armed, nuclear-powered, 

undersea autonomous torpedo.

Russia possesses significant advantages in its nuclear weapons production capacity and in 

non-strategic nuclear forces over the U.S. and allies. It is also building a large, diverse, and 

modern set of non-strategic systems that are dual-capable (may be armed with nuclear or 

conventional weapons). These theater- and tactical-range systems are not accountable 

under the New START Treaty and Russia’s non-strategic nuclear weapons modernization 

is increasing the total number of such 

weapons in its arsenal, while 

significantly improving its delivery 

capabilities. This includes the 

production, possession, and flight 

testing of a ground-launched cruise 

missile in violation of the INF Treaty. 

Moscow believes these systems may 

provide useful options for escalation

advantage. Finally, despite Moscow’s 

frequent criticism of U.S. missile 

defense, Russia is also modernizing its 

long-standing nuclear-armed ballistic 

missile defense system and designing a 

new ballistic missile defense 

interceptor.

Russian President Vladimir Putin and Defense Minister General 

Sergey Shoigu in the National Defense Council Center. (Photo by 

Russian Ministry of Defense)

“Nuclear ambitions in the US and Russia over the last 20 years have evolved in 

opposite directions. Reducing the role of nuclear weapons in US security 

strategy is a US objective, while Russia is pursuing new concepts and 

capabilities for expanding the role of nuclear weapons in its security strategy.”

U.S. National Intelligence Council, 2012
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NUCLEAR POSTURE REVIEW

Russia’s increased reliance on nuclear capabilities to include coercive threats, nuclear 

modernization programs, refusal to negotiate any limits on its non-strategic nuclear forces, 

and its decision to violate the INF Treaty and other commitments all clearly indicate that 

Russia has rebuffed repeated U.S. efforts to reduce the salience, role, and number of 

nuclear weapons.

RESPONDING TO RUSSIA’S INF TREATY VIOLATION

In July 2014, the United States declared Russia to be in violation of the INF Treaty for 

the development of the SSC-8 ground-launched cruise missile system. The United States 

has since pressed Russia to return to compliance with the Treaty.

The North Atlantic Council has emphasized that, “full compliance with the INF Treaty 

is essential,” and “identified a Russian missile system that raises serious concerns; NATO 

urges Russia to address these concerns in a substantial and transparent way.” – December 

15th, 2017

RESPONSE MEASURES:

Diplomatic Measures – The United States continues to seek a diplomatic resolution 

through all viable channels, including the INF’s Special Verification Commission. Allies 

have emphasized that a situation whereby the United States and other parties are abiding 

by the Treaty, and Russia were not, would be a grave and urgent concern.

Economic Measures – The United States has sanctioned Russian companies involved in 

the development and manufacture of Russia’s prohibited cruise missile system.

Military Measures – The United States is commencing INF Treaty-compliant research 

and development by reviewing military concepts and options for conventional, groundlaunched, intermediate-range missile systems.
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NUCLEAR POSTURE REVIEW

China

Consistent with Chinese President 

Xi’s statement at the 19th Party 

Congress that China’s military will 

be “fully transformed into a first tier 

force” by 2050, China continues to 

increase the number, capabilities, 

and protection of its nuclear forces. 

While China’s declaratory policy and 

doctrine have not changed, its lack of 

transparency regarding the scope and 

scale of its nuclear modernization 

program raises questions regarding 

its future intent. China has 

developed a new road-mobile 

strategic intercontinental ballistic missile (ICBM), a new multi-warhead version of its DF5 silo-based ICBM, and its most advanced ballistic missile submarine armed with new 

submarine-launched ballistic missiles (SLBM). It has also announced development of a new 

nuclear-capable strategic bomber, giving China a nuclear triad. China has also deployed a 

nuclear-capable precision guided DF-26 intermediate-range ballistic missile capable of 

attacking land and naval targets. As with Russia, despite criticizing U.S. homeland missile 

defense—which is directed against limited missile threats—China has announced that it is 

testing a new mid-course missile defense system, plans to develop sea-based mid-course 

ballistic missile defense, and is developing theater ballistic missile defense systems, but has 

provided few details.

North Korea 

The security environment has worsened given these developments and the threats posed by 

further proliferation of nuclear weapons. 

North Korea has accelerated its provocative pursuit of nuclear weapons and missile 

capabilities, and expressed explicit threats to use nuclear weapons against the United States 

and its allies in the region. North Korean officials insist that they will not give up nuclear 

weapons, and North Korea may now be only months away from the capability to strike the 

United States with nuclear-armed ballistic missiles. In the past few years, North Korea has 

dramatically increased its missile flight testing, most recently including the testing of 

China's CSS-X-20 ICBM on parade in 2015. (Photo by Xinhua News)
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NUCLEAR POSTURE REVIEW

intercontinental-range missiles capable of reaching the U.S. homeland. It has conducted 

six nuclear tests since 2006, including a test of a significantly higher-yield device. Further, 

North Korea continues to produce plutonium and highly-enriched uranium for nuclear 

weapons. Given North Korea’s current and emerging nuclear capabilities; existing 

chemical, biological, and conventional capabilities; and extremely provocative rhetoric and 

actions, it has come to pose an urgent and unpredictable threat to the United States, allies, 

and partners. Consequently, the United States reaffirms that North Korea’s illicit nuclear 

program must be completely, verifiably, and irreversibly eliminated, resulting in a Korean 

Peninsula free of nuclear weapons.

North Korea’s continued pursuit of nuclear weapons capabilities poses the most immediate 

and dire proliferation threat to international security and stability. In addition to explicit 

nuclear threats enabled by North 

Korea’s development of nuclear 

weapons and delivery systems, 

North Korea poses a “horizontal” 

proliferation threat as a potential 

source of nuclear weapons or nuclear 

materials for other proliferators. 

North Korea’s nuclear weapons 

program also increases nuclear 

proliferation pressures on nonnuclear weapon states that North 

Korea directly and explicitly 

threatens with nuclear attack.

“North Korea’s nuclear weapons and missile programs will continue to pose a 

serious threat to US interests and to the security environment in East Asia in 

2017. North Korea’s export of ballistic missiles and associated materials to 

several countries, including Iran and Syria, and its assistance to Syria’s 

construction of a nuclear reactor, destroyed in 2007, illustrate its willingness 

to proliferate dangerous technologies.”

Director of National Intelligence, Daniel R. Coats,

Worldwide Threat Assessment, 2017

Kim Jong-un inspecting the Hwasong-14 ICBM. (Photo by the Korean 

Central News Agency)
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NUCLEAR POSTURE REVIEW

Iran 

Iran, too, poses proliferation threats. Iran’s Supreme Leader, Ayatollah Ali Khamenei, has 

most recently stated that, “America is the number one enemy of our nation.” While Iran 

has agreed to constraints on its nuclear program in the Joint Comprehensive Plan of Action 

(JCPOA), absent extensive international actions many of the agreement’s restrictions on 

Iran’s nuclear program will end by 2031. In addition, Iran retains the technological 

capability and much of the capacity necessary to develop a nuclear weapon within one year 

of a decision to do so. Iran’s development of increasingly long-range ballistic missile 

capabilities, and its aggressive strategy 

and activities to destabilize 

neighboring governments, raises 

questions about its long-term 

commitment to foregoing nuclear 

weapons capability. Were Iran to 

pursue nuclear weapons after JCPOA 

restrictions end, pressures on other 

countries in the region to acquire 

their own nuclear weapons would 

increase.

Nuclear terrorism remains a threat to 

the United States and to international 

security and stability. Preventing the 

illicit acquisition of a nuclear weapon, nuclear materials, or related technology and 

expertise by a violent extremist organization is a significant U.S. national security priority. 

The more states--particularly rogue states--that possess nuclear weapons or the materials, 

technology, and knowledge required to make them, the greater the potential risk of 

terrorist acquisition. Further, given the nature of terrorist ideologies, we must assume that 

they would employ a nuclear weapon were they to acquire one.

Uncertainties Regarding the Future Security 

Environment and the Threats it May Pose

The significant and rapid worsening of the international security environment since the 

2010 NPR demonstrates that unanticipated developments and uncertainty about near- and 

long-term threats to the United States, allies, and partners are factors we must consider in 

formulating U.S. nuclear policy, strategy, and posture. These uncertainties are a concern 

in the near term, and potentially profound in the long term. Because this NPR lays the 

policy, strategy, and programmatic foundation for sustaining and replacing the entire U.S. 

Iranian test launch of a modified Fateh-110. (Photo by the Iranian 

Ministry of Defense)
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NUCLEAR POSTURE REVIEW

nuclear force needed to address threats decades into the future, it focuses on the 

implications of such uncertainties.

There are two forms of uncertainty regarding the future security environment which U.S. 

nuclear policy, strategy, and posture must take into account. The first is geopolitical 

uncertainty. This includes the potential for rapid shifts in how other states view the United 

States, its allies, and partners; changing alignments among other states; and relative power 

shifts in the international system. The collapse of the government of a nuclear-armed state 

or a so-called “proliferation cascade” would also fall in this category.

The second form of uncertainty is technological. This includes the potential for 

unanticipated technological breakthroughs in the application of existing technologies, or 

the development of wholly new technologies, that change the nature of the threats we face 

and the capabilities required to address them effectively. For example, breakthroughs that 

would render U.S. nuclear forces or U.S. command and control of those forces highly 

vulnerable to attack would dramatically affect U.S. nuclear force requirements, policy, and 

posture. The proliferation of highly-lethal biological weapons is another example.

Such geopolitical and technological uncertainties are, fundamentally, unpredictable, 

particularly over the long term. Yet, it is near certain that unanticipated developments will 

arise. Consequently, we must take them into account to the extent possible as we plan the 

U.S. nuclear forces and related capabilities needed now and in future decades. Ensuring 

that U.S. nuclear capabilities have the flexibility and attributes necessary to respond to the 

possible shocks of a changing threat environment is our responsibility to future generations.
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III. Why U.S. Nuclear Capabilities?

“Our nuclear deterrent underwrites all courses of diplomacy 

and every military operation...there is a direct line between a 

safe, secure, and reliable nuclear deterrent...and our 

responsibility as global defenders of freedom.” 

U.S. Air Force Chief of Staff, General David Goldfein, 2017
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III. Why u.S. nuclear capabilities

U.S. Nuclear Capabilities

The fundamental reasons why U.S. nuclear capabilities and deterrence strategies are 

necessary for U.S., allied, and partner security are readily apparent. As Secretary of 

Defense Mattis has observed, “a safe, secure, and effective nuclear deterrent is there to 

ensure a war that can never be won, is never fought.” The deterrence effects they provide 

are unique and essential to preventing adversary nuclear attacks, which is the highest 

defense priority of the United States. 

U.S. nuclear capabilities cannot prevent all conflict or provocations, and should not be 

expected to do so. But, the U.S. triad of strategic bombers, ICBMs, and SLBMs, 

supplemented by dual-capable aircraft (DCA), overshadows any adversary’s calculations of 

the prospective benefits of aggression and thus contributes uniquely both to deterring 

nuclear and non-nuclear attack and to assuring allies and partners. The triad and DCA are 

essential for these purposes, and will be so for the foreseeable future. As the Bipartisan 

Congressional Strategic Posture Commission—led by former Defense Secretaries William 

Perry and James Schlesinger—emphasized in 2009, “The conditions that might make 

possible the global elimination of nuclear weapons are not present today and their creation 

would require a fundamental transformation of the world political order.” That 

fundamental transformation has not since taken place, nor is it emerging.

For centuries prior to the era of nuclear deterrence, periodic and catastrophic wars among 

Great Powers were the norm, waged with ever more destructive weapons and inflicting 

B-2 Stealth Bomber and two F-15 Strike Eagle aircraft.

Air Force Captain discusses U.S. Strategic Command’s bomber and intercontinental ballistic missile capabilities with 

visiting Navy Reserve personnel.

An unarmed AGM-86B Air-Launched Cruise Missile is released from a B-52H Stratofortress.

Machinist's Mate (Weapons) 3rd Class, assigned to the OHIO-class ballistic-missile submarine USS Louisiana 

(SSBN 743) receives hands-on training inside the Weapons Launch Control Team Trainer at Trident Training 

Facility at Naval Base Kitsap-Bangor.
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NUCLEAR POSTURE REVIEW

ever higher casualties and damage to society. During the first half of the 20th century and 

just prior to the introduction of U.S. nuclear deterrence, the world suffered 80—100 

million fatalities over the relatively short war years of World Wars I and II, averaging over 

30,000 fatalities per day.

Since the introduction of U.S. nuclear deterrence, U.S. nuclear capabilities have made 

essential contributions to the deterrence of nuclear and non-nuclear aggression. The 

subsequent absence of Great Power conflict has coincided with a dramatic and sustained 

reduction in the number of lives lost to war globally, as illustrated by Figure 2.

Non-nuclear forces also play essential deterrence roles. Alone, however, they do not 

provide comparable deterrence effects, as reflected by the periodic and catastrophic failures 

of conventional deterrence to prevent Great Power wars throughout history. Similarly, 

conventional forces alone do not adequately assure many allies and partners. Rather, these 

states place enormous value on U.S. extended nuclear deterrence, which correspondingly 

is also key to non-proliferation.

NUCLEAR 

ERA

CONVENTIONAL ERA

WARTIME FATALITIES % OF THE WORLD POPULATION (CIVILIAN AND MILITARY)

2.5%

2%

1.5%

1600 1700 1800 1900

% OF TOTAL POPULATION

1650 1750 1850 1950 2000

WWI

1.12%

1.75%

0.4%

<0.01%

WWII

1%

0.5%

2.27%

1.15%

1.31%

 Figure 2. Wartime Fatalities Percentage of World Population

Data from the DoD Historical Office
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NUCLEAR POSTURE REVIEW

Properly sustained U.S. nuclear deterrence helps prevent attacks against the United States, 

allies, and partners and the return to the frequent Great Power warfare of past centuries. 

In the absence of U.S. nuclear deterrence, the United States, allies, and partners would be 

vulnerable to coercion and attack by adversaries who retain or expand nuclear arms and 

increasingly lethal non-nuclear capabilities. Until the “fundamental transformation of the 

world political order” takes place, U.S. nuclear weapons remain necessary to prevent war 

and safeguard the Nation.
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NUCLEAR POSTURE REVIEW

IV. Enduring National Objectives 

and the Roles of Nuclear Weapons 

in U.S. National Security Strategy

“We believe that by improving deterrence across the broad 

spectrum, we will reduce to an even lower point the probability 

of a nuclear clash between ourselves and other major powers.” 

Secretary of Defense James Schlesinger, 1974
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NUCLEAR POSTURE REVIEW

IV. Enduring National Objectives and the Roles of Nuclear Weapons in U.S. National Security Strategy

The highest U.S. nuclear policy and strategy priority is to deter potential adversaries from 

nuclear attack of any scale. However, deterring nuclear attack is not the sole purpose of 

nuclear weapons. Given the diverse threats and profound uncertainties of the current and 

future threat environment, U.S. nuclear forces play the following critical roles in U.S. 

national security strategy. They contribute to the:

› Deterrence of nuclear and non-nuclear attack;

› Assurance of allies and partners; 

› Achievement of U.S. objectives if deterrence fails; and 

› Capacity to hedge against an uncertain future. 

These roles are complementary and interrelated, and we must assess the adequacy of U.S. 

nuclear forces against each role and the strategy designed to fulfill it. Preventing 

proliferation and denying terrorists access to finished weapons, material, or expertise are 

also key considerations in the elaboration of U.S. nuclear policy and requirements. These 

multiple roles and objectives are the guiding pillars for U.S. nuclear policy, strategy, and 

requirements.

Deterrence of Nuclear and Non-Nuclear Attack

The highest U.S. nuclear policy and 

strategy priority is to deter potential 

adversaries from nuclear attack of 

any scale. Potential adversaries must 

understand that the United States has 

the will and response options 

necessary to deter nuclear attack 

under any conditions.

The specific application of 

deterrence strategies changes across 

time and circumstance, but the 

fundamental nature of deterrence 

endures: it is about decisively 

influencing an adversary’s decision 

calculus to prevent attack or the 

escalation of a conflict. Potential 

adversaries must understand that 

aggression against the United States, 

allies, and partners will fail and result in intolerable costs for them. We deter attacks by 

ensuring the expected lack of success and prospective costs far outweigh any achievable 

gains.

An unarmed Trident II D5 missile launches from the Ohio-class 

fleet ballistic-missile submarine USS Maryland (SSBN 738) off the 

coast of Florida. The test launch was part of the U.S. Navy Strategic 

Systems Programs demonstration and shakedown operation 

certification process. The successful launch certified the readiness 

of an SSBN crew and the operational performance of the 

submarine's strategic weapons system before returning to 

operational availability (U.S. Navy Photo)
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NUCLEAR POSTURE REVIEW

U.S. deterrence strategy has always integrated multiple instruments of national power to 

deter nuclear and non-nuclear attack. Integrating and exercising all instruments of power 

has become increasingly important as potential adversaries integrate their military 

capabilities, expanding the range of potential challenges to be deterred. This is particularly 

true of threats from potential adversaries of limited nuclear escalation and non-nuclear 

strategic attack.

For U.S. deterrence to be effective across the emerging range of threats and contexts, 

nuclear-armed potential adversaries must recognize that their threats of nuclear escalation 

do not give them freedom to pursue non-nuclear aggression. Potential adversaries must 

understand that: 1) the United States is able to identify them and hold them accountable 

for acts of aggression, including new forms of aggression; 2) we will defeat non-nuclear 

strategic attacks; and, 3) any nuclear escalation will fail to achieve their objectives, and will 

instead result in unacceptable consequences for them.

For effective deterrence, the United States will acquire and maintain the full range of 

capabilities needed to ensure that nuclear or non-nuclear aggression against the United 

States, allies, and partners will fail to achieve its objectives and carry with it the credible 

risk of intolerable consequences for the adversary. U.S. forces will ensure their ability to 

integrate nuclear and non-nuclear military planning and operations. Combatant 

Commands and Service components will be organized and resourced for this mission, and 

will plan, train, and exercise to integrate U.S. nuclear and non-nuclear forces and operate 

in the face of adversary nuclear threats and attacks. The United States will coordinate 

integration activities with allies facing nuclear threats, and will examine opportunities for 

additional allied burden sharing in the nuclear deterrence mission.

An important element of maintaining effective deterrence is the articulation of U.S. 

declaratory policy regarding the potential employment of nuclear weapons:

The United States would only consider the employment of nuclear weapons in extreme circumstances 

to defend the vital interests of the United States, its allies, and partners. Extreme circumstances 

could include significant non-nuclear strategic attacks. Significant non-nuclear strategic attacks 

include, but are not limited to, attacks on the U.S., allied, or partner civilian population or 

infrastructure, and attacks on U.S. or allied nuclear forces, their command and control, or warning 

and attack assessment capabilities.

The United States will not use or threaten to use nuclear weapons against non-nuclear weapons 

states that are party to the NPT and in compliance with their nuclear non-proliferation obligations.

Given the potential of significant non-nuclear strategic attacks, the United States reserves the right 

to make any adjustment in the assurance that may be warranted by the evolution and proliferation 

of non-nuclear strategic attack technologies and U.S. capabilities to counter that threat.
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NUCLEAR POSTURE REVIEW

To help preserve deterrence and the assurance of allies and partners, the United States has 

never adopted a “no first use” policy and, given the contemporary threat environment, such 

a policy is not justified today. It remains the policy of the United States to retain some 

ambiguity regarding the precise circumstances that might lead to a U.S. nuclear response.

In addition, the United States will maintain a portion of its nuclear forces on alert day-today, and retain the option of launching those forces promptly. This posture maximizes 

decision time and preserves the range of U.S. response options. It also makes clear to 

potential adversaries that they can have no confidence in strategies intended to destroy our 

nuclear deterrent forces in a surprise first strike. 

The de-alerting of U.S. ICBMs would create the potential for dangerous deterrence 

instabilities by rendering them vulnerable to a potential first strike and compelling the 

United States to rush to re-alert in a crisis or conflict. Further, U.S. ICBMs are not on 

“hair-trigger alert,” as sometimes mistakenly is claimed. As the bipartisan 2009 PerrySchlesinger Commission report stated, hair trigger alert “is simply an erroneous 

characterization of the issue. The alert postures of both countries [the United States and 

the Russian Federation] are in fact highly stable. They are subject to multiple layers of 

control, ensuring clear civilian and indeed Presidential decision-making.” Over more than 

half a century, the U.S. has established a series of measures and protocols to ensure that 

ICBMs are safe, secure, and under constant control. Any U.S. decision to employ nuclear 

weapons would follow a deliberative process. Finally, the United States will continue its 

long-standing practice of open-ocean targeting of its strategic nuclear forces day-to-day as 

a confidence and security building measure.

Assurance of Allies and Partners

The United States has extended 

nuclear deterrence commitments 

that assure European, Asian, and 

Pacific allies. The United States will 

ensure the credibility and 

effectiveness of those commitments.

Assurance is a common goal and 

advances our common security 

interests. It is based on collaboration 

with allies and partners to deter or 

defeat the threats we face. It includes 

sustained allied dialogues to 

understand each other’s threat 

perceptions and to arrive at a shared 

understanding of how best to 

U.S. Air Force F-35A Lightning IIs and Japanese Air Self Defense 

Force F-15 Eagles fly in formation during bi-lateral training December 

4, 2017, over the Pacific Ocean. (U.S. Air Force photo)
23

NUCLEAR POSTURE REVIEW

demonstrate our collective capabilities and resolve. No country should doubt the strength 

of our extended deterrence commitments or the strength of U.S. and allied capabilities to 

deter, or if necessary defeat, any potential adversary’s nuclear or non-nuclear aggression.

In many cases, effectively assuring allies and partners depends on their confidence in the 

credibility of U.S. extended nuclear deterrence. They have reaffirmed that extended 

nuclear deterrence is essential to their security, enabling most to eschew possession of 

nuclear weapons and thereby contributing to U.S. non-proliferation goals.

Achieve U.S. Objectives Should Deterrence Fail

For deterrence to be credible, the 

United States must prepare to 

respond effectively if deterrence 

were to fail, in ways that will achieve 

U.S. objectives while protecting 

U.S., allied, and partner interests. 

Non-nuclear capabilities can 

complement but not replace U.S. 

nuclear capabilities for this purpose.

All U.S. Presidents since 1945 have 

considered U.S. employment of 

nuclear weapons only in extreme 

circumstances and for defensive 

purposes. If deterrence fails, the 

initiation and conduct of nuclear operations would adhere to the law of armed conflict and 

the Uniform Code of Military Justice. The United States will strive to end any conflict and 

restore deterrence at the lowest level of damage possible for the United States, allies, and 

partners, and minimize civilian damage to the extent possible consistent with achieving 

objectives.

Every U.S. administration over the past six decades has called for flexible and limited U.S. 

nuclear response options, in part to support the goal of reestablishing deterrence following 

its possible failure. This is not because reestablishing deterrence is certain, but because it 

may be achievable in some cases and contribute to limiting damage, to the extent feasible, 

to the United States, allies, and partners. The goal of limiting damage if deterrence fails in 

a regional contingency calls for robust adaptive planning to defeat and defend against 

attacks, including missile defense and capabilities to locate, track, and target mobile systems 

of regional adversaries. These and other non-nuclear capabilities, which we are now 

strengthening, can complement but not replace U.S. nuclear forces for this purpose. In the 

case of missile threats from regional actors in particular, U.S. missile defense and offensive 

options provide the basis for significant damage limitation in the event deterrence fails.

A radar navigator assigned to the 2nd Bomb Wing, Barksdale Air Force 

Base, La., watches monitors on a B-52 Stratofortress during a mission 

in support of bomber assurance and deterrence operations at Royal Air 

Force Fairford, England, September 19, 2017. (Air Force photo)
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NUCLEAR POSTURE REVIEW

Hedge against an Uncertain Future 

The United States will continue 

efforts to create a more cooperative 

and benign security environment, 

but must also hedge against 

prospective and unanticipated risks. 

Nuclear capabilities alone do not 

provide the basis for hedging against 

future uncertainty; non-nuclear 

forces also play a critical role. 

However, U.S. nuclear capabilities 

provide a necessary, unique, and 

currently irreplaceable contribution.

Hedging strategies help reduce risk 

and avoid threats that otherwise may 

emerge over time. Given the 

increasing prominence of nuclear 

weapons in the defense policies and 

strategies of Russia and China, and the uncertainties of the future threat environment, 

particularly from illicit North Korean nuclear and missile programs, U.S. nuclear 

capabilities and the ability to quickly modify them are essential to mitigate or overcome 

risk. The capacity to hedge contributes to deterrence and can help reduce potential 

adversaries’ confidence that they can gain an advantage via a “break out” or expansion of 

nuclear capabilities.

Our hedging strategies must also help mitigate and overcome unexpected technical risks 

throughout the life cycle of U.S. nuclear capabilities, and must mitigate risk in the 

development, deployment, and operation of U.S. nuclear forces. As we acquire forces, 

and those forces age, this requires a framework to continually assess risks and threats, 

identify whether to accept or mitigate risks, and guide development of appropriate and 

effective solutions.

Airman 1st Class, 90th Missile Maintenance Squadron maintainer, 

removes the screws holding the nose point of a Minuteman III 

ICBM to the rest of the reentry system inside a payload transporter 

in the F.E. Warren Air Force Base, Wyo., missile complex, August

24, 2016. The system was separated into two parts and secured 

inside a payload transporter. The 90th MMXS maintains 150 

Minuteman III ICBMs and the associated LFs spread throughout 

three states and 9,600 square miles. (U.S. Air Force photo)
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NUCLEAR POSTURE REVIEW

V. Tailored Strategies 

and Flexible Capabilities 

“The challenges that each situation may present, such as time, place 

and circumstance, are distinct. Therefore, flexibility and adaptiveness 

are essential in a defence planning process that can never be informed 

reliably about the future contexts for action and requirements.” 

 Professor Colin S. Gray, 2017
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NUCLEAR POSTURE REVIEW

V. tailored strategies and flexible capabilities

Tailored Deterrence

There is no “one size fits all” for deterrence. The requirements for effective deterrence 

vary given the need to address the unique perceptions, goals, interests, strengths, strategies, 

and vulnerabilities of different potential adversaries. The deterrence strategy effective 

against one potential adversary may not deter another. Consequently, the United States 

will apply a tailored approach to effectively deter across a spectrum of adversaries, threats, 

and contexts.

Tailored deterrence strategies are designed to communicate the costs of aggression to 

potential adversaries, taking into consideration how they uniquely calculate costs and risks. 

This calls for a diverse range and mix of U.S. deterrence options, now and into the future, 

to ensure strategic stability.

Tailored deterrence also calls for on-going analyses to adapt our strategies to different 

potential adversaries and contingencies. These analyses address how potential adversaries 

define unacceptable damage, and how the United States can credibly communicate to them 

the risks and costs that would accompany their aggression. Adjusting our deterrence 

strategies accordingly is what it means to tailor deterrence.

Flexible Capabilities

Flexibility means having the appropriate range and mix of nuclear and other capabilities 

required to tailor deterrence strategies now and into the future, and to fulfill the other roles 

An unarmed Trident II D5 missile launches from the OHIO-class fleet ballistic-missile submarine USS Maryland (SSBN 738) off the coast of Florida.

Two U.S. Air Force B-1B Lancers (not pictured) joined up with Republic of Korea air force F-15s during a 10-hour mission from Andersen Air Force Base, 

Guam, into Japanese airspace and over the Korean Peninsula.

A U.S. Air Force T-38 Talon aircraft and B-2 Spirit aircraft fly in formation during a training mission over Whiteman Air Force Base.

Air Force Technical Sergeant and Staff Sergeant test communications equipment required for mobile nuclear command and control capabilities at Offutt Air 

Force Base.
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NUCLEAR POSTURE REVIEW

of nuclear weapons in U.S. national security strategy. Flexibility must address a spectrum 

of adversaries and threats and enable adjustments over time. U.S. nuclear strategies, forces, 

and NC3 must be increasingly flexible to sustain that range of capabilities and options.

The United States has understood the value of flexibility for nuclear deterrence for six 

decades, but its importance is now magnified by the emerging diversity of nuclear and nonnuclear strategic threats and the dynamism and uncertainties of the security environment. 

This need for flexibility to tailor U.S. capabilities and strategies to meet future 

requirements and unanticipated developments runs contrary to a rigid, continuing policy 

of “no new nuclear capabilities.” Potential adversaries do not stand still. On the contrary, 

they seek to identify and exploit weaknesses in U.S. capabilities and strategy. Thus, U.S.

future force requirements for deterrence cannot prudently be considered fixed. The 

United States must be capable of developing and deploying new capabilities, if necessary, 

to deter, assure, achieve U.S. objectives if deterrence fails, and hedge against uncertainty.
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VI. U.S. Strategies to Counter 

Contemporary Threats 

“The number one priority of the Department of Defense is that we 

maintain a safe, secure and effective nuclear deterrent so we make 

certain those weapons are never used.”

Secretary of Defense James Mattis, August 2017
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VI. U.S. Strategies to Counter Contemporary Threats

A Tailored Strategy for Russia

Russia is not the Soviet Union and the Cold War is long over. However, despite our best 

efforts to sustain a positive relationship, Russia now perceives the United States and NATO 

as its principal opponent and impediment to realizing its destabilizing geopolitical goals in 

Eurasia.

Russia has significantly increased 

the capabilities of its non-nuclear 

forces to project power into regions 

adjacent to Russia and, as 

previously discussed, has violated 

multiple treaty obligations and 

other important commitments. 

Most concerning are Russia’s 

national security policies, strategy, 

and doctrine that include an 

emphasis on the threat of limited 

nuclear escalation, and its 

continuing development and 

fielding of increasingly diverse and 

expanding nuclear capabilities. Moscow threatens and exercises limited nuclear first use, 

suggesting a mistaken expectation that coercive nuclear threats or limited first use could 

paralyze the United States and NATO and thereby end a conflict on terms favorable to 

Russia. Some in the United States refer to this as Russia’s “escalate to de-escalate” doctrine. 

“De-escalation” in this sense follows from Moscow’s mistaken assumption of Western 

capitulation on terms favorable to Moscow.

Effective U.S. deterrence of Russian nuclear attack and non-nuclear strategic attack now 

requires ensuring that the Russian leadership does not miscalculate regarding the 

consequences of limited nuclear first use, either regionally or against the United States 

itself. Russia must instead understand that nuclear first-use, however limited, will fail to 

achieve its objectives, fundamentally alter the nature of a conflict, and trigger incalculable 

and intolerable costs for Moscow. Our strategy will ensure Russia understands that any use 

of nuclear weapons, however limited, is unacceptable.

The U.S. deterrent tailored to Russia, therefore, will be capable of holding at risk, under 

all conditions, what Russia’s leadership most values. It will pose insurmountable difficulties 

to any Russian strategy of aggression against the United States, its allies, or partners and 

ensure the credible prospect of unacceptably dire costs to the Russian leadership if it were 

to choose aggression. 

Russian SS-27 Mod 2 ICBM on parade in Moscow. (Photo by the 

Russian Ministry of Defense)
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NUCLEAR POSTURE REVIEW

This strategy will ensure Russia understands it has no advantages in will, non-nuclear 

capabilities, or nuclear escalation options that enable it to anticipate a possible benefit from 

non-nuclear aggression or limited nuclear escalation. Correcting any Russian 

misperceptions along these lines is important to maintaining deterrence in Europe and 

strategic stability.

Correspondingly, at the 2016 NATO Summit, the Alliance emphasized that, “no one should 

doubt NATO’s resolve if the security of any of its members were to be threatened. NATO 

will maintain the full range of capabilities necessary to deter and defend against any threat 

to the safety and security of our populations, wherever it should arise.”

To correct any Russian misperceptions of advantage and credibly deter Russian nuclear or 

non-nuclear strategic attacks—which could now include attacks against U.S. NC3—the 

President must have a range of limited and graduated options, including a variety of delivery 

systems and explosive yields. These requirements put a premium on the survivability, 

flexibility and readiness of Western nuclear and non-nuclear capabilities to hold diverse 

types of Russian targets at risk throughout a crisis or conflict, and point to the continuing 

great value of the flexibility inherent in the combination of the U.S. nuclear triad, U.S. and 

other NATO non-strategic nuclear forces deployed in Europe, and the nuclear forces of 

our British and French allies.

A Tailored Strategy for China

China’s military modernization and 

pursuit of regional dominance have 

emerged as a majorchallenge to U.S. 

interests in Asia. It has adopted an 

increasingly assertive posture in 

disputes with its neighbors, many of 

whom are U.S. allies or partners. 

These encompass a variety of 

historical and border disputes, 

including over territorial 

boundaries, claims to contested 

island territory, and an islandbuilding campaign in the South 

China Sea. China possesses nuclear 

warheads on protected ICBMs and SLBMs capable of reaching the United States and 

nuclear-armed, theater-range ballistic missiles capable of reaching U.S. territory, allies, 

partners, forces, and bases in the region. China’s expanding non-nuclear military 

capabilities include space and cyber warfare capabilities that could decisively affect the 

outcome of a conflict.

A JIN-class Type 094 ballistic missile submarine. (Photo by the 

People’s Liberation Army-Navy)
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NUCLEAR POSTURE REVIEW

China is developing capabilities to counter U.S. power projection operations in the region 

and to deny the United States the capability and freedom of action to protect U.S., allied, 

and partner interests. Direct military conflict between China and the United States would 

have the potential for nuclear escalation. Our tailored strategy for China is designed to 

prevent Beijing from mistakenly concluding that it could secure an advantage through the 

limited use of its theater nuclear capabilities or that any use of nuclear weapons, however 

limited, is acceptable.

The United States will maintain the capability to credibly threaten intolerable damage as 

Chinese leaders calculate costs and benefits, such that the costs incurred as a result of 

Chinese nuclear employment, at any level of escalation, would vastly outweigh any benefit.

The United States is prepared to respond decisively to Chinese non-nuclear or nuclear 

aggression. U.S. exercises in the Asia-Pacific region, among other objectives, demonstrate 

this preparedness, as will increasing the range of graduated nuclear response options 

available to the President. Both steps will strengthen the credibility of our deterrence 

strategy and improve our capability to respond effectively to Chinese limited nuclear use if 

deterrence were to fail. The United States will also continue to seek a meaningful dialogue 

with China on our respective nuclear policies, doctrine, and capabilities in pursuit of a 

peaceful security environment and stable relations.

A Tailored Strategy for North Korea

North Korea poses a clear and grave threat to U.S. and allied security. North Korea openly 

states that its missiles are intended to deliver nuclear strikes against U.S., South Korean, 

and Japanese cities. North Korean state agencies have made numerous reckless nuclear 

threats, such as, “Japan is no longer needed to exist near us,” and Japan “should be sunken 

into the sea by [North Korea’s] nuclear bomb,” and “Let’s reduce the U.S. mainland to 

ashes and darkness.”

A complete, verifiable and irreversible nuclear-free Korean peninsula is a long-standing 

U.S. objective. Yet, North Korea has prioritized continuing investments in nuclear 

capabilities over the well-being of the North Korean people, and also possesses significant 

conventional, cyber, chemical, and biological capabilities. Its expansive nuclear and missile 

programs suggest the potential for nuclear first use in support of conventional operations. 

The Kim regime may mistakenly believe that nuclear capabilities give it freedom to engage 

in a spectrum of bold provocations, including military attacks on South Korean territory 

and naval vessels, and test launching missiles over Japan.
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NUCLEAR POSTURE REVIEW

For North Korea, the survival of the 

Kim regime is paramount. Our 

deterrence strategy for North Korea 

makes clear that any North Korean 

nuclear attack against the United 

States or its allies and partners is 

unacceptable and will result in the 

end of that regime. There is no 

scenario in which the Kim regime 

could employ nuclear weapons and 

survive. Further, we will hold the 

Kim regime fully responsible for any 

transfer of nuclear weapons 

technology, material or expertise to 

any state or non-state actor.

North Korea relies on hardened and deeply buried facilities to secure the Kim regime and 

its key military and command and control capabilities. It uses underground facilities and 

natural terrain features to protect North Korean military forces. Consequently, the United 

States will continue to field a range of conventional and nuclear capabilities able to hold 

such targets at risk.

In addition to ensuring the ability to impose intolerable costs on the Kim regime, the United 

States and allies have defensive and offensive capabilities to intercept and otherwise defeat 

North Korea’s missile capabilities, and thereby limit or preclude North Korea’s ability to 

conduct effective missile strikes. Japan and South Korea have long expressed support for 

these capabilities. Although North Korea’s missile forces are expanding and increasingly 

mobile, U.S. and allied missile defenses are increasingly capable against North Korea’s 

missile threat, and the United States has the early warning systems and strike capabilities 

necessary to degrade North Korean missile capabilities prior to launch. We will continually 

improve these defensive capabilities as needed to stay ahead of North Korean missile threats 

if they continue to grow, while also taking steps to preclude an arms race with China or 

Russia.

A Tailored Strategy for Iran

Iran views U.S. influence in the Middle East as the foremost threat to Iran’s goal to establish 

itself as the dominant regional power. Iran is committed to increasing its influence over 

neighboring countries and countering U.S. influence. This goal directly threatens U.S. 

allies and partners, and Iran’s defense policy, strategy, and force structure indicate an 

attempt to create exploitable military advantages. 

Kim Jong-un observing a recent missile launch. (Photo by the Korean 

Central News Agency)
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NUCLEAR POSTURE REVIEW

Iran continues to invest in the largest 

missile program in the Middle East 

and could, in the future, threaten or 

deliver nuclear weapons were Iran to 

acquire them following expiration of 

the JCPOA, in violation of the NPT 

and its nuclear non-proliferation 

obligations. Iran also is developing 

other non-nuclear military 

capabilities, including cruise missile 

systems and cyber warfare 

capabilities for offensive operations. 

It may also continue to invest in 

chemical and biological weapons.

Many of the JCPOA’s key 

constraints on Iran’s nuclear 

program end by 2031, shortening the time it would take Iran to produce enough weaponsgrade nuclear material for a nuclear weapon. Iran’s development of increasingly accurate 

and sophisticated ballistic missiles gives it the capability to threaten U.S. forces, allies, and 

partners in and outside the region. Were Iran to decide to acquire nuclear weapons, 

pressures on other countries in the region to acquire their own nuclear weapons would 

increase.

Our deterrence strategy is designed to ensure that the Iranian leadership understands that 

any non-nuclear strategic attack against the United States, allies, and partners would be 

defeated, and that the cost would outweigh any benefits. There is no plausible scenario in 

which Iran may anticipate benefit from launching a strategic attack. Consequently, U.S 

deterrence strategy includes the capabilities necessary to defeat Iranian non-nuclear, 

strategic capabilities, including the U.S. defensive and offensive systems capable of 

precluding or degrading Tehran’s missile threats. The United States will continue to 

strengthen these capabilities as necessary to stay ahead of Iranian threats as they grow. 

Doing so will enhance U.S. security and that of our regional allies and partners.

Extended Deterrence and Tailored Assurance

The United States has effectively assured allies and partners for decades. The United States 

affirms its commitment to the security of its allies and partners, who are concerned about 

the negative trends in the security environment. This concern is evident both in Europe, 

where there are understandable allied fears of Russia’s nuclear and non-nuclear threats and 

its use of military force against neighbors, and in Asia, where there are understandable allied 

fears of China’s military rise and North Korea’s extreme nuclear and non-nuclear threats.

U.S. Ambassador to the United Nations Nikki Haley discusses evidence 

of Iran’s destabilizing activities in the Middle East and Iran’s effort to 

cover up continued violations of U.N. resolutions during a news 

conference at Joint Base Anacostia-Bolling in Washington, D.C., 

December 14, 2017. (DoD photo)
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NUCLEAR POSTURE REVIEW

Our ability to continue assuring allies and partners is challenged by the range and diversity 

of potential adversaries and the threats they pose. The United States extends deterrence to 

over 30 countries with different views about the threat environment and the credibility of 

U.S. security commitments. Similar to deterrence, there is no “one size fits all” strategy 

for assurance. Assurance measures must continually adapt to the shifting requirements of 

a highly dynamic threat environment. Our assurance strategies are tailored to the differing 

requirements of the Euro-Atlantic and Asia-Pacific regions, accounting for the differing 

security environments, potential adversary capabilities, and varying alliance structures.

Effective deterrence is the foundation for effective assurance. Allies under the U.S. nuclear 

umbrella, and potential adversaries, should not doubt our extended deterrence 

commitments or our ability and willingness to fulfill them. In support of U.S. extended 

deterrence commitments, the United States will maintain the capabilities necessary to deter 

effectively and, if necessary, to respond effectively and decisively across the spectrum of 

potential nuclear and non-nuclear scenarios. Critically, for deterrence and assurance 

purposes, we will retain the capability to adjust our nuclear force structure as required by 

the security environment. We will develop the necessary infrastructure, capabilities, and 

political arrangements, now and in the future, to deny adversaries any confidence that they 

can achieve their regional objectives through nuclear threats or nuclear use.

Assurance also flows from a shared view of the security environment, including: shared 

interests at stake; deterrence challenges and required capabilities; roles, responsibilities, 

and expectations; and the appropriate combined response to different conflict scenarios. 

Consequently, communication and consultation on policy, strategy and capabilities are 

essential for assurance and will be sustained.

Strengthening Deterrence in Europe

The U.S. commitment to NATO is 

unwavering. A strong, cohesive 

nuclear Alliance is the most effective 

means of deterring aggression and 

promoting peace and stability in the

Euro-Atlantic region. NATO 

followed the U.S. post-Cold War 

trend in deemphasizing the role of 

nuclear weapons in NATO’s 

deterrence and defense posture, but 

the Alliance never lost sight of the 

fundamental purpose NATO’s nuclear 

capabilities play in preserving peace, 

preventing coercion, and deterring 

aggression.

A Russian Sukhoi Su-24 attack aircraft makes a very low altitude pass 

by USS Donald Cook (DDG 75) April 12, 2016. Donald Cook, an 

Arleigh Burke-class guided-missile destroyer forward deployed to 

Rota, Spain, is conducting a routine patrol in the U.S. 6th Fleet area 

of operations in support of U.S. national security interests in Europe. 

(U.S. Navy photo)
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NUCLEAR POSTURE REVIEW

At both the 2014 Wales and 2016 Warsaw summits, NATO recognized that Russia’s 

activities and policies have reduced stability and security, increased unpredictability, and 

introduced new dangers into the security environment. Importantly, NATO is addressing 

the changed security environment to make clear that any employment of nuclear weapons 

against NATO, however limited, would not only fundamentally alter the nature of a 

conflict, but would result in unacceptable costs to an adversary that would far outweigh the 

benefit it could hope to achieve. The Alliance has already initiated measures to ensure that 

NATO’s overall deterrence and defense posture, including its nuclear forces, remain 

capable of addressing any potential adversary’s doctrine and capabilities.

In support of these efforts, the United States will consult and work cooperatively with 

NATO allies to:

› Enhance the readiness and survivability of NATO DCA, improve capabilities required 

to increase their operational effectiveness, and account for adversary nuclear and nonnuclear capabilities;

› Promote the broadest possible participation of Allies in their agreed burden sharing 

arrangements regarding the DCA mission, nuclear mission support, and nuclear 

infrastructure;

› Replace aging aircraft and weapons systems with modernized or life-extended 

equivalents as they age out;

› Enhance the realism of training and exercise programs to ensure the Alliance can 

effectively integrate nuclear and non-nuclear operations, if deterrence fails; and

› Ensure the NATO NC3 system is modernized to enable appropriate consultations and 

effective nuclear operations, improve its survivability, resilience, and flexibility in the 

most stressful threat environments.

The United States will make available its strategic nuclear forces, and commit nuclear 

weapons forward-deployed to Europe, to the defense of NATO. These forces provide an 

essential political and military link between Europe and North America and are the supreme 

guarantee of Alliance security. Combined with the independent strategic nuclear forces of 

the United Kingdom and France, as well as Allied burden sharing arrangements, NATO’s 

overall nuclear deterrence forces are essential to the Alliance’s deterrence and defense 

posture now and in the future.

Strengthening Deterrence in Asia

The U.S. commitment to our allies and partners in the Asia-Pacific region is unwavering. 

As in Europe, strong, cohesive alliances and credible deterrence measures are the most 

effective means of assurance in the Asia-Pacific region. However, North Korea, China, and 

Russia each present unique, and in some ways more complex, threats to our allies and 
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NUCLEAR POSTURE REVIEW

interests in the Asia-Pacific region. 

Further, the perception and immediacy 

of these threats is unique to different 

allies.

In addition, our alliance structure in Asia 

is different than it is in Europe. Rather 

than a single multinational alliance, in 

Asia we have a series of bilateral 

arrangements with varying degrees of 

multilateral cooperation across different 

missions. Our nuclear posture, too, is 

different. Following the Cold War, the 

United States removed all of its nuclear 

weapons based in Asia and instead relied on strategic nuclear capabilities, complemented 

by a sea-launched cruise missile (TLAM-N) to extend nuclear deterrence to our allies. 

With the retirement of the TLAM-N following the 2010 NPR, the United States currently 

relies almost exclusively on its strategic nuclear capabilities for nuclear deterrence and the 

assurance of allies in the region. For these reasons, consultation and cooperative 

arrangements in the Asia-Pacific region are appropriately different than those in Europe.

To maintain credible extended deterrence and thus effective assurance in this complex 

environment, the United States will:

› Maintain integrated, flexible, and adaptable U.S. nuclear and non-nuclear capabilities; 

› Continue to invest in missile defenses against North Korean missile threats;

› Demonstrate with allies our joint commitment to deterrence through military 

exercises; and, 

› Work with our allies to improve our shared understanding of nuclear dangers and 

corresponding deterrence requirements through continued consultative dialogues.

Hedge against Diverse Uncertainties

The United States will tailor its hedging strategy across the range of potential adversaries 

and be prepared to meet future risks and challenges that may emerge, but cannot be 

characterized with certainty today. The combination of a highly dynamic security 

environment and the rapid advancement and spread of military technology creates a range 

of possible threat developments for which we must be prepared. Additionally, the United 

States is embarking on a nuclear force sustainment and replacement program which is just 

in time. This requires a high degree of concurrency and synchronization and, thus, has the 

potential for scheduling shortfalls. We cannot predict with confidence when or if any of 

these potential challenges will occur, but there always exists the potential for geopolitical 

The U.S.-Japan Bilateral Commission on Civil Nuclear 

Cooperation tour an Aerial Measuring System helicopter. 

(Photo provided by NNSA)
38

NUCLEAR POSTURE REVIEW

or technological surprise. Therefore, we must, and will, posture our nuclear capabilities 

to hedge against multiple potential risks and threat developments. 

We will, for example, hedge against the potential rapid growth or emergence of nuclear 

and non-nuclear strategic threats, including chemical, biological, cyber, and large-scale 

conventional aggression. The capacity to hedge helps ensure our ability to sustain effective 

deterrence and assurance amid unexpected change.

Our hedge strategy addresses four categories of potential risk:

› Geopolitical risk includes the emergence of new adversaries, expansion of adversary 

nuclear forces, changes in adversary strategy and doctrine, new alignments among 

adversaries, and the further proliferation of nuclear weapons.

› Technological risk includes technical challenges resulting from a breakdown of a key 

element of U.S. nuclear forces, or from adversaries’ technological breakthroughs, that 

create a new threat to U.S. nuclear deterrent capabilities.

› Operational risk includes the potential for operational shortfalls that reduce the 

effectiveness of U.S. nuclear forces. It includes reduced availability of deployed forces, 

intelligence collection gaps that inhibit identification or characterization of designated 

targets, and any unmet requirement needed to sustain effective deterrence.

› Programmatic risk includes potential risks to the U.S. sustainment of adequate nuclear 

capabilities such as delays to maintenance programs, the age-out of legacy nuclear 

systems earlier or more precipitously than anticipated, and an inability to produce 

needed quantities of unique nuclear materials. These risks are particularly acute today 

because key elements of the U.S. nuclear acquisition and production infrastructure 

have “atrophied,” as described in 2008 by the Secretaries of Defense and Energy. They 

noted “existing U.S. nuclear weapons—most of which were designed 20 to 30 years 

ago—are being maintained well beyond the service life for which they were designed.” 

There is no further margin for delaying U.S. sustainment and replacement programs 

for our existing nuclear capabilities and nuclear weapons infrastructure. We will avoid 

shortfalls in the next decade only by carefully managing programmatic risk to those 

programs.

The U.S strategy for hedging against unexpected challenges is based on two parallel 

approaches: reducing the likelihood that challenges will emerge in the categories of 

geopolitical, technological, operational, and programmatic risk; and, reducing the harm 

that would result if preventive measures prove inadequate. This two-track hedging strategy 

will help guide the capabilities and size of U.S. nuclear forces and supporting infrastructure.

Preventing the Emergence of Challenges

We will counter the emergence of challenges to U.S. nuclear strategy by emphasizing: 

1) the early detection of potential problems; 2) opportunities for risk reduction through 
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NUCLEAR POSTURE REVIEW

diplomacy; and 3) dissuading adversaries from attempting to challenge U.S., allied, and 

partner security.

Detect and resolve potential challenges early. Detecting and addressing problems before 

they arise is the most direct way to reduce the likelihood that dangerous technological or 

operational surprises will emerge. To do so, the Department of Energy’s (DOE) National 

Nuclear Security Administration (NNSA) will continue to conduct robust nuclear weapons 

surveillance and experimental programs to identify issues early enough to help prevent 

technical breakdowns, operational shortfalls, and programmatic challenges. DoD will 

continue to conduct a weapon system test and evaluation program to identify emerging 

issues early. DoD and NNSA will also work together to conduct ongoing evaluations of the 

current and potential future security environments. This will include threat-based analyses 

of what potential adversaries are doing or considering today, as well as what is possible in 

light of projected advancement and diffusion of technology. Finally, the United States will 

remain at the forefront of science and technology to reduce the likelihood of technological 

surprise.

Risk reduction through diplomacy. We will seek opportunities for diplomatic agreements 

that reduce the likelihood of future security challenges via mutual restraints that reduce the 

potential for miscalculation in crisis or conflict. Treaties and agreements for this purpose 

can benefit U.S. security when they are verifiable and compliance can reasonably be 

expected and enforced as necessary.

Dissuade adversaries from seeking advantage. We will reduce the likelihood of geopolitical 

challenges by being prepared to respond effectively to changes in the security environment, 

and being seen as so capable. Adversaries will be less likely to seek strategic advantage 

through arms competition if the United States clearly demonstrates the capacity and will to 

meet any such challenge. Therefore, in preparing to respond to geopolitical challenges, we 

will prioritize measures that would help reduce the likelihood that adversaries will choose 

to challenge us in the first place.

Mitigating the Potential Consequences of Future Challenges

The United States can hedge in two complementary ways. One is by having a robust nuclear 

weapon production infrastructure that has the design, engineering, and manufacturing 

capabilities needed to quickly produce new or additional weapons needed to address

changes in the threat environment. Another approach is to retain a significant non-deployed 

inventory of weapons that can be added to current delivery vehicles to address geopolitical 

threat or technical failure.

Given the current state of our nuclear weapon production infrastructure, the United States 

will mitigate the potential consequences of future challenges to U.S. nuclear strategy by 

sustaining a reserve nuclear stockpile of non-deployed weapons able to support U.S. 

nuclear strategies amid unexpected change. This requires maintaining the U.S. capacity to 
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NUCLEAR POSTURE REVIEW

upload hedge weapons onto existing delivery platforms to augment the deployed force as 

necessary if, for example, an unexpected operational or technical problem were to arise in 

U.S. forces.

DoD will prioritize its nuclear hedge 

planning to sustain specific force 

attributes in the event of a 

technological or geopolitical 

challenge that threatens an element of 

U.S. nuclear forces. These attributes 

include survivability, the ability to 

penetrate adversary defenses, the 

ability to visibly signal deterrence 

messages, prompt response, and a 

range of warhead yield options.

This strategy for risk mitigation helps 

to hedge against the possibility that an

operational or technical problem or 

adversary breakthrough would compromise the effectiveness of our nuclear forces. It also 

helps to preclude nuclear arms competition by communicating to adversaries that we can

deny them useful advantage through their arms racing.

Flexibility supports our strategies for deterring adversaries and assuring allies by providing

options for tailoring and responding effectively to future challenges. We will reduce future 

risk exposure by ensuring that flexibility is built into and sustained in our current and future 

nuclear force structure. This applies to delivery systems, platforms, warheads, command 

and control, and early warning and attack assessment.

Across the nuclear enterprise, the United States will target investments in personnel, 

programs, and technologies that strengthen our ability to adjust course as necessary in 

response to emerging challenges. In order to identify and address potential needs, the 

United States will support and expand as necessary the NNSA Stockpile Responsiveness 

Program, the Navy SSBN Security Technology Program, and the Air Force Nuclear 

Weapons Center Red Team Program.

In addition, DoD will explore prioritization of existing research and development funding 

for advanced nuclear delivery system technology and prototyping capabilities. This will 

support the U.S. development of hedging options and focus, as necessary, on the rapid 

development of nuclear delivery systems, alternative basing modes, and capabilities for 

defeating advanced air and missile defenses.

Researcher prepares a global burst detector subsystem for a test in 

the flight test chamber at Sandia National Laboratories in 

Albuquerque, N.M., August 4, 2016. (Photo by Randy Montoya)
41

NUCLEAR POSTURE REVIEW

VII. Current and Future 

U.S. Nuclear Capabilities

“Our nuclear deterrent is nearing a crossroads. To date, we have preserved 

this deterrent by extending the lifespan of legacy nuclear forces and 

infrastructure—in many cases for decades beyond what was originally 

intended. But these systems will not remain viable indefinitely. In fact, 

we are now at a point where we must concurrently modernize the entire 

nuclear triad and the infrastructure that enables its effectiveness.”

Vice Chairman, Joint Chiefs of Staff, General Paul Selva, 2017
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NUCLEAR POSTURE REVIEW

VII. Current and Future U.S. Nuclear Capabilities

U.S. Nuclear Enterprise Personnel

Effective deterrence would not be 

possible without the thousands of 

members of the United States Armed 

Forces and civilian personnel who 

dedicate their professional lives to the 

deterrence of war and protecting the 

Nation. These exceptional men and 

women are held to the most rigorous 

standards and make the most vital 

contribution to U.S. nuclear capabilities 

and deterrence.

As former Secretary of Defense Ashton 

Carter stated in 2016 when speaking to 

Air Force Service members at Minot Air 

Force Base in North Dakota, “America’s nuclear deterrence is the bedrock of our 

security...You deter large-scale nuclear attack against the United Sates and our allies. You 

help convince potential adversaries that they can’t escalate their way out of a failed 

conventional aggression.”

The Service members and civilians involved in the nuclear deterrence mission do so with 

little public recognition or fanfare. Theirs is an unsung duty of the utmost importance. 

They deserve the support of the American people for the safety, security, and stability they 

provide the Nation, and indeed the world. The Service reforms we have accordingly 

implemented were long overdue, and the Department of Defense remains fully committed 

to properly supporting the Service members who protect the United States against nuclear 

threats.

The Strategic Nuclear Triad

For more than six decades, U.S. officials have emphasized the need for U.S. nuclear 

capabilities, including NC3, with the attributes necessary to deter adversaries, assure allies, 

and achieve U.S. objectives should deterrence fail. They have called for the survivability 

and flexibility of U.S. nuclear forces to provide the United States with multiple options to 

deter effectively and respond as necessary to different threats and circumstances. This 

requirement is now magnified by the need to tailor U.S. strategies to a broader range of 

adversaries and contingencies and to hedge against unanticipated developments.

Today’s strategic nuclear triad consists of: nuclear ballistic missile submarines (SSBNs) 

armed with SLBMs; land-based ICBMs; and strategic bombers carrying gravity bombs and 

Airman 1st Class stands guard at Minot Air Force Base, N.D., 

October 31, 2017, during Global Thunder 18. (U.S. Air Force 

photo)
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NUCLEAR POSTURE REVIEW

air-launched cruise missiles (ALCMs). The triad, with supporting NC3 and non-strategic 

nuclear forces, provides diversity and flexibility to tailor strategies for deterring, assuring, 

achieving objectives should deterrence fail, and hedging.

The increasing need for this diversity and flexibility, in turn, is one of the primary reasons 

why sustaining and replacing the nuclear triad and non-strategic nuclear capabilities is 

necessary. The multiplicity of platforms, weapons, and modes of operation inherent in the 

triad and U.S. non-strategic nuclear forces, provide a significant margin of flexibility and 

resilience. Designing flexibility into the triad sustainment and replacement programs will 

help ensure that we maintain this margin in the future. DoD and NNSA will design 

flexibility into U.S. nuclear capabilities during concept exploration and preliminary design 

phases that enable us to modify systems in the future at lower cost and with greater speed.

The triad must be considered as a 

whole because it functions as a 

whole, with each leg essential to 

overall effectiveness. As Secretary of 

Defense Mattis concluded regarding 

deterrence requirements and the 

triad, “I also have looked at – I have 

questioned the triad, and I cannot 

solve the deterrent problem 

reducing it from a triad. If I want to 

send the most compelling message, I 

have been persuaded that the triad in 

its framework is – is the right way to 

go.” The triad’s synergy and 

overlapping attributes help ensure 

the enduring survivability of our deterrence capabilities against attack and our capacity to 

hold a range of adversary targets at risk throughout a crisis or conflict. Eliminating any leg 

of the triad would greatly ease adversary attack planning and allow an adversary to 

concentrate resources and attention on defeating the remaining two legs.

The U.S. nuclear triad provides key nuclear force attributes required to maintain sufficient 

diversity and flexibility. These include:

› Survivable. The force and NC3 resilience needed to survive any potential adversary 

attack and endure throughout crises and conflict.

› Forward Deployable. The mobility and range needed to temporarily or permanently 

relocate some U.S. nuclear capability to allied or partner territory for needed 

political or military effect.

Marine Corps General Joe Dunford, chairman of the Joint Chiefs of 

Staff, meets with the crew of a B-52H at Minot Air Force Base, N.D., 

November 2, 2016. (DoD photo)
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NUCLEAR POSTURE REVIEW

› Diverse and Graduated Options. The availability of forces with the spectrum of yield 

options, weapon types, and delivery options necessary to support the most effective 

tailoring of strategies across a range of adversaries and contingencies.

› Accurate Delivery. The precision needed to hold adversary assets at risk while 

minimizing unintended effects.

› Penetrating. The capacity to counter active and passive defenses, including hardened 

and buried facilities, to pose credible deterrent threats and achieve military objectives 

with high confidence.

› Responsive. The capacity to deploy and employ forces as promptly as is necessary to 

pose credible threats.

› Diversity of Ranges. The availability of forces with a spectrum of range options 

necessary to support the most effective tailoring of strategies.

› Diversity of Trajectories. The capacity to locate forces at multiple geographical 

locations and with multiple flight profiles to complicate adversary active and passive 

defense planning.

› Visible. The capacity to display national will and capabilities as desired for signaling 

purposes throughout crisis and conflict.

› Weapon Reallocation. The capacity to change target information quickly to enable 

adaptive planning and effective employment.

Together with effective NC3, these force attributes provide the flexible and resilient 

capabilities needed to support four essential functions:

› Provide survivable, responsive capabilities to ensure adversaries do not attempt a 

disarming first strike;

› Demonstrate resolve through the positioning of forces, messaging, and flexible 

response options;

› Ensure the U.S. can respond to a broad range of contingencies with tailored options;

and

› Mitigate the risk of a technological failure or adversary breakthrough while providing 

adaptability to changes in the security environment.

The Three Legs of the Strategic Nuclear Triad

Sea-Based Deterrent Force

The United States currently operates OHIO-class SSBNs equipped with Trident II (D5) 

SLBMs to provide its sea-based deterrent force. Ballistic missile submarines are the most 

survivable leg of the triad. When on patrol, SSBNs are, at present, virtually undetectable, 
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NUCLEAR POSTURE REVIEW

and there are no known, near-term credible threats to the survivability of the SSBN force. 

Nevertheless, we will continue to hedge against the possibility that advances in antisubmarine warfare could make the SSBN force less survivable in the future. 

SLBMs also possess a number of other 

needed attributes. Their 

intercontinental range and constant 

readiness allows them to hold targets 

at risk throughout Eurasia from their 

launch areas in the Atlantic and Pacific 

oceans. They are equipped with highly 

accurate, high-yield warheads, which 

enhance their ability to hold many 

types of targets at risk. SLBMs are also 

prompt. Traveling at hypersonic 

speed, SLBMs can reach their targets 

quickly after launch. The SSBN force 

can upload additional warheads if 

necessary, contributing to the U.S. 

hedge capacity.

Finally, SSBNs are highly mobile. They can demonstrate U.S. nuclear presence and 

commitment for deterrence and assurance purposes via foreign port calls if desired.

The first OHIO-class SSBN entered service in 1981 and the others entered service through 

the late 1990s. It was originally designed for a 30-year service life and was subsequently 

extended to 42 years, the longest of any submarine in U.S. history. The D5 SLBM was first 

deployed in 1990, and its service life is being extended to run through the end of the last 

OHIO-class SSBN’s lifetime in 2042. The OHIO-class cannot be extended further. In 

coming decades, advances in adversary anti-submarine warfare and missile defense 

capabilities could challenge the effectiveness of current SSBN and SLBM systems.

Land-Based Deterrent Force

The ICBM force consists of 400, single-warhead Minuteman III ICBMs deployed in 450 

underground silos dispersed across several states. These ICBMs are the most responsive leg 

of the triad because they are in constant readiness and communication can be achieved most 

expeditiously. This readiness helps preclude a potentially destabilizing rush to alert in a 

crisis.

The OHIO-class ballistic-missile submarine USS Kentucky (SSBN 737) 

transits the Hood Canal as the boat returns to Naval Base KitsapBangor following the boat's first strategic deterrent patrol since 2011. 

(U.S. Navy photo)
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NUCLEAR POSTURE REVIEW

The ICBM force is highly survivable 

against any but a large-scale nuclear 

attack. To destroy U.S. ICBMs on the 

ground, an adversary would need to 

launch a precisely coordinated attack 

with hundreds of high-yield and 

accurate warheads. This is an 

insurmountable challenge for any 

potential adversary today, with the 

exception of Russia. In contrast, in the 

absence of our ICBM force, a large 

proportion of our strategic nuclear 

triad, including SSBNs in port and nonalert bombers, could be subject to an 

attempted nuclear first strike involving 

a relatively small number of nuclear 

weapons.

The capability to launch ICBMs promptly means that no adversary can be confident in its 

ability to destroy them prior to launch. This option contributes to deterrence of a nuclear 

first strike attack. The United States will continue to maintain open-ocean targeting of its 

strategic nuclear forces day-to-day as a confidence and security building measure. In 

addition, similar to SLBMs, we will act to ensure that the ICBM force remains effective 

despite potential advances in adversary ballistic missile defenses.

The ICBM force has high-yield, accurate weapons and intercontinental range, enabling it to 

hold at risk targets throughout Eurasia. It also is prompt and can reach any target in 30 

minutes or less. In addition, a portion of the ICBM force can be uploaded if there is a need 

to do so—a capability that contributes to our hedging capacity.

The Minuteman III ICBM was first deployed in 1970, with a planned 10-year service life. 

A series of life extension programs have kept Minuteman III viable, but component aging 

and inventory attrition are rapidly driving it to the end of its sustainability. From 2002—

2012, Minuteman III underwent a life extension program intended to maintain its viability 

to 2030. By that time, its 60 years of operation will make it the oldest deployed strategic 

ballistic missile in the world. The Minuteman III service life cannot be extended further. 

In addition, Minuteman III will have increasing difficulty penetrating future adversary 

defenses.

Air-Based Deterrent Force

Heavy bombers are the most flexible and visible leg of the triad. The air leg consists of 46 

nuclear capable B-52H and 20 nuclear capable B-2A “stealth” strategic bombers supported 

An unarmed Minuteman III intercontinental ballistic missile during 

an operational test at 2:10 a.m. Pacific Daylight Time Wednesday, 

Aug. 2, 2017, at Vandenberg Air Force Base, Calif. (U.S. Air Force 

photo)
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NUCLEAR POSTURE REVIEW

by a fleet of Air Force refueling aircraft. While these bombers and air refueling aircraft are 

not maintained on day-to-day alert, as they were until 1992, they can be alerted and 

dispersed, improving their pre-launch survivability. Bombers and DCA can also be forward 

deployed to help deter regional aggression and assure distant allies.

Unlike ICBMs or SLBMs, bombers typically require hours to reach their targets. The longer 

flight times and ability to recall bombers in flight contribute to their flexibility. Flights 

abroad display U.S. capabilities and resolve, providing effective signaling for deterrence 

and assurance, including in times of tension. Bombers can be refueled in flight, giving them 

virtually unlimited range and endurance. In recent years, B-52 and B-2A bombers have 

carried out Bomber Assurance and Deterrence missions, including nonstop, round-trip 

flights from the continental United States to the Korean peninsula.

Bombers can carry a variety of 

nuclear weapons with diverse 

attributes that contribute to the 

flexibility valuable for deterrence in 

different circumstances. The gravity 

bombs carried by B-2A bombers and 

the ALCMs carried by B-52H 

bombers provide multiple yield 

options. In addition, the B83-1 and 

B61-11 can hold at risk a variety of 

protected targets. As a result, both 

will be retained in the stockpile, at 

least until there is sufficient 

confidence in the B61-12 gravity 

bomb that will become available in 2020. 

The bombers also play a critical role in the U.S. hedging strategy. Their significant payload 

capacity provides the ability to upload additional weapons, in particular stand-off cruise 

missiles, in response to possible geopolitical surprises such as adversary nuclear “breakout” 

scenarios. Similarly, the upload potential of the U.S. bomber force provides an important 

hedge against programmatic risk in the strategic replacement programs.

The B-2A bomber is now the only long-range, nuclear capable U.S. aircraft that can 

penetrate advanced air defenses. Beginning in 1982, our B-52H bombers were equipped 

with ALCMs in response to steady advances in adversary air defense systems. Armed with 

ALCMs, the B-52H can stay outside adversary air defenses and remain effective. The 

ALCM, however, is now more than 25 years past its design life and faces continuously 

improving adversary air defense systems. Life extension programs (LEPs) are underway to 

ensure the ALCM can be maintained until its replacement, the Long-Range Stand-Off 

(LRSO) cruise missile, becomes available.

Air Force Captain flies a B-52H Stratofortress during a training mission 

over North Dakota, January 31, 2017. (Air Force photo)
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NUCLEAR POSTURE REVIEW

Non-Strategic Nuclear Weapons

During the Cold War, the United States possessed 

large numbers and a wide range of non-strategic 

nuclear weapons, also known as theater or tactical 

nuclear weapons. However, we have since retired 

and dismantled almost all of those weapons. 

Current U.S. non-strategic nuclear forces consist 

exclusively of B61 gravity bombs carried by F-15E 

DCA, supported by responsive air refueling 

aircraft. Several NATO allies also provide DCA 

capable of delivering U.S. forward-deployed 

nuclear weapons. The forthcoming B61-12 gravity 

bomb will replace earlier versions of the B61, and 

be available for these DCA beginning in 2021.

U.S. and NATO DCA, together with U.S. gravity 

bombs, are forward deployed in European NATO 

countries. Their forward presence contributes 

significantly to the deterrence of potential 

adversaries and the assurance of allies. Their 

presence is a clear deterrence signal to any potential 

adversary that the United States possesses the forward-deployed capability to respond to 

escalation. If necessary, the United States has the ability to deploy DCA and nuclear 

weapons to other regions, such as Northeast Asia. 

In sum, U.S. nuclear capabilities include the variety of attributes and flexibility needed to 

tailor deterrence to a range of potential adversaries and contingencies, assure allies, achieve 

our objectives if deterrence fails, and hedge against multiple future risks and uncertainties. 

No single leg of the triad offers all of these attributes, but they are available in the triad as 

whole, in combination with non-strategic nuclear forces. Relying on life extension 

programs since the 1980s, and multiple delays in the recapitalization of our nuclear force, 

has removed all schedule margin between the necessary retirement of our legacy nuclear 

systems and the fielding of planned replacement systems. Consequently, we will move 

these forward without delay.

The Department of Defense Replacement Program

The United States will replace its strategic nuclear triad and sustain the warheads it carries 

– there is no higher priority for national defense. DoD and DOE will prioritize and fund 

their respective nuclear delivery system and warhead programs to remain on schedule for 

Sandia National Laboratory mechanical engineer 

adjusts a microphone for an acoustic text on a 

B-61-12 system.
49

NUCLEAR POSTURE REVIEW

synchronized delivery, and they will seek opportunities to accelerate programs where cost 

effective.

The United States has a two-pronged approach to sustaining the legacy nuclear systems to 

the extent practicable and to begin the replacement of retiring, legacy systems by the mid2020s. We will sustain these systems until the planned replacement systems are fielded.

This two-pronged approach responds to emerging threats and is codified by the 2017 

National Defense Authorization Act, which directs that, “in support of a strong and credible 

nuclear deterrent, the United States must—(A) maintain a nuclear force with a diverse, 

flexible range of nuclear yield and delivery modes that are ready, capable, and credible; and 

(B) afford the highest priority to the modernization of the nuclear triad, dual-capable 

aircraft, and related command and control elements.”

The Sea-Based Deterrent Force

The COLUMBIA-class program will deliver a minimum of 12 SSBNs to replace the current 

OHIO fleet and is designed to provide required capabilities for decades. The first 

COLUMBIA-class SSBN will become operational in 2031. COLUMBIA will include a 

number of technological features and preserve the flexibility to upgrade to ensure the fleet 

remains survivable.

Under present building and fielding plans, the number of SSBNs available for deployment 

will reduce to ten during the 2030s as the OHIO SSBN retires and the COLUMBIA 

completes production. During the period of fielding COLUMBIA, there will be little-tono margin for adjusting to an unforeseen event that would force an SSBN into unscheduled 

maintenance or early retirement. Thus, the United States will ensure that the COLUMBIA 

program stays on schedule and will continue to ensure that the OHIO SSBN remains 

operationally effective and survivable until replaced. Given the need to retire the OHIO 

at 42 years, there is no schedule margin for delay without degrading the critical attributes 

that the sea-based leg of the triad provides.

We will place similar emphasis on the timely replacement of the D5 SLBM. The D5 SLBM 

is in the early stages of a life extension that will allow it to be deployed until 2042 on both 

OHIO and COLUMBIA SSBNs. The Navy will begin studies in 2020 to define a costeffective, credible, and effective SLBM that we can deploy throughout the service life of 

the COLUMBIA SSBN.

ICBMs

To sustain the ICBM’s critical contributions to the triad, the United States must and will 

begin fielding its replacement, the Ground-Based Strategic Deterrent (GBSD), on time in 

2029. The GBSD program will modernize 450 ICBM launch facilities to support fielding 
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NUCLEAR POSTURE REVIEW

400 ICBMs to replace the retiring Minuteman III after six decades or more of service. This 

will provide an ICBM system effective for decades into the future.

Strategic Bombers and Air-Delivered Weapons

The United States will sustain and modernize the B-52H and B-2A to ensure they remain 

effective into the future. Given the continuing proliferation and improvement of adversary

air defense capabilities and the continued aging of the B-52H, the ALCM, and the B-2A, 

the United States has initiated a program to develop and deploy the next-generation 

bomber, the B-21 Raider. The B-21 Raider will first supplement, and eventually replace 

elements of the conventional and nuclear-capable bomber force beginning in the mid2020s.

The replacement for the aging ALCM – the LRSO – is a modern air-launched cruise missile. 

The LRSO program will maintain into the future our bomber capability to deliver standoff weapons that can penetrate and survive advanced integrated air defense systems, thus 

holding targets at risk anywhere on Earth.

Arming our force of strategic bombers with LRSO is critical to ensuring their continuing 

effectiveness in the face of improving air defenses and to provide a diverse range of response 

options. The LRSO will enable the B-52H to remain an effective part of the nuclear-capable 

bomber force and preserve upload potential as a key hedge against unforeseen technical and

geopolitical challenges. The B-21 will be able to deliver both gravity bombs and the LRSO, 

the latter supporting the long-term effectiveness of the bomber leg. Crucial to the success 

of the heavy bomber force is a viable aerial refueling capability, which also needs 

recapitalization.

The United States is also incorporating nuclear capability onto the F-35, to be used by the 

United States and NATO allies, as a replacement for the current aging DCA. Improved 

DCA readiness and the arrival of the F-35, a “fifth generation aircraft,” in conjunction with 

the ongoing B61-12 gravity bomb LEP, will preserve the DCA contribution to regional 

deterrence stability and assurance. In parallel with its warhead LEP, the B61-12 will be 

equipped with a guidance tail kit to sustain the military capability of existing B61 variants. 

As is the case with the sustainment and replacement programs necessary to maintain the 

triad, the programs supporting the DCA mission must be completed on time.

If this planned triad and DCA replacement program experiences delays, or if existing 

systems reach obsolescence earlier than expected, fielded systems will age out before 

replacements are available and the United States will face potentially significant gaps in its 

diverse and flexible capabilities needed to deter, assure, achieve objectives if deterrence 

fails, and hedge against future uncertainty. Delays to the SSBN and SLBM replacement 

programs would reduce the survivability and flexibility of U.S. nuclear capabilities and 

challenge our ability to maintain rough parity with Russian strategic deployments, even at 

the reduced levels set by New START. Delays in the GBSD program, accompanied by a 
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NUCLEAR POSTURE REVIEW

rapid age-out of our ICBM force, would dramatically reduce the scale of attack required 

foran adversary to threaten much of the U.S. deterrent forces in a first-strike attack. Delays 

in the B-21 bomber program or associated bomber weapons would reduce the ability of our 

strategic forces to penetrate adversary air defenses, limit the diversity of our response 

options, and compromise our ability to send the visible deterrence and assurance signals for 

which strategic bombers are particularly well suited.

Flexible and Secure Nuclear Capabilities: 

An Affordable Priority

Throughout past decades, senior U.S. officials have emphasized that the highest priority of 

the Department of Defense is deterring nuclear attack and, therefore, sustaining the nuclear 

capabilities necessary to deter. More recently, Secretary of Defense Mattis, former 

Secretary of Defense Carter, and the Chairman of the Joint Chiefs, General Joseph 

Dunford, have all emphasized the priority of the nuclear deterrence mission and the 

necessity of our nuclear sustainment and replacement programs.

While estimates of the cost to sustain and replace U.S. nuclear capabilities vary, based on 

the timeframe considered and how they account for various elements of the program, even 

the highest of these projections place the highpoint of the future cost at approximately 6.4 

percent of the current DoD budget. Maintaining and operating our current aging nuclear 

forces now requires between two and three percent of the DoD budget, and the 

replacement program to rebuild the triad for decades of service will peak for several years 

at only approximately four percent beyond the existing sustainment level of spending. This 

6.4 percent of the current DoD budget required for the long-term program represents less 

than one percent of today’s overall federal budget. As indicated by Figure 3, this level of 

spending compares favorably to the 10.6 percent of the DoD budget required during the 

last such investment period in the 1980s, which at the time was almost 3.7 percent of the 

federal budget, and the 17.1 percent of the DoD budget required in the early 1960s.

“What we want to do is to deter. Nobody wants to have a war. The only thing 

more expensive than deterrence is actually fighting a war, and the only thing 

more expensive than fighting a war is fighting one and losing.”

U.S. Army Chief of Staff, General Mark A. Milley, 2016
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NUCLEAR POSTURE REVIEW

The projected DoD costs of sustaining and replacing the nuclear capabilities needed to 

support U.S. national security strategy, while substantial, are moderate in historical terms 

and represent a small fraction of the DoD budget. Given the criticality of effective U.S. 

nuclear deterrence to the assurance of allies, and, most importantly, the safety of the 

American people, there is no doubt that these programs are both necessary and affordable.

Enhancing Deterrence with Non-Strategic Nuclear 

Capabilities

Existing elements of the nuclear force replacement program predate the dramatic 

deterioration of the strategic environment. To meet the emerging requirements of U.S. 

strategy, the United States will now pursue select supplements to the replacement program

to enhance the flexibility and responsiveness of U.S. nuclear forces. It is a reflection of the 

versatility and flexibility of the U.S. triad that only modest supplements are now required 

in this much more challenging threat environment. 1962 1965 1968 1971 1974 1977 1980 1983 1986 1989 1992 1995 1998 2001

2004200720102013201620192022202520282031203420372040

Legacy Triad

and Sustainment

16%

14%

12%

10%

8%

6%

4%

2%

0%

FISCAL YEAR

PERCENT OF DOD BUDGET

DOD NUCLEAR ENTERPRISE FUNDING

Legacy Triad

and Sustainment 2029:

Peak Recapitalization of Nuclear Enterprise 

Funding, including 100% of B-21 funding

TOTAL TRIAD: 6.4%

of DoD Budget

1984:

TOTAL TRIAD: 10.6% 

of DoD Budget

Recapitalization

1962:

TOTAL TRIAD: 17.1% 

of DoD Budget

Peak Recapitalization:

3.7% of DoD Budget

Sustainment:

2.7% of DoD Budget

18%

Figure 3. Cost of DoD Nuclear Force Replacement

Data provided by DoD
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NUCLEAR POSTURE REVIEW

These supplements will enhance deterrence by denying potential adversaries any mistaken 

confidence that limited nuclear employment can provide a useful advantage over the United 

States and its allies. Russia’s belief that limited nuclear first use, potentially including lowyield weapons, can provide such an advantage is based, in part, on Moscow’s perception 

that its greater number and variety of non-strategic nuclear systems provide a coercive 

advantage in crises and at lower levels of conflict. Recent Russian statements on this 

evolving nuclear weapons doctrine appear to lower the threshold for Moscow’s first-use of 

RUSSIA’S NON-STRATEGIC NUCLEAR CHALLENGE

Figure 4. Russia’s Non-Strategic Nuclear Challenge

Data provided by the DoD

Russia is modernizing an active stockpile of up to 2,000 non-strategic nuclear weapons, including those employable 

by ships, planes, and ground forces. These include air-to-surface missiles, short range ballistic missiles, gravity 

bombs, and depth charges for medium-range bombers, tactical bombers, and naval aviation, as well as anti-ship, 

anti-submarine, and anti-aircraft missiles and torpedoes for surface ships and submarines, a nuclear groundlaunched cruise missile in violation of the 1987 INF Treaty, and Moscow’s antiballistic missile system.

RUSSIA

UNITED 

STATES

 

CRBM

SRBM

Torpedo

Anti-Submarine Missile

Anti-Ship Missile

GLCM Depth Charges

Gravity 

Weapon

KEY LAND SEA AIR

Anti-Aircraft Missile

Anti-Ballistic Missile Air-to-Surface Missile

Gravity 

Weapon
54

NUCLEAR POSTURE REVIEW

nuclear weapons. Russia demonstrates its perception of the advantage these systems

provide through numerous exercises and statements. Correcting this mistaken Russian 

perception is a strategic imperative. North Korea is illicitly developing a range of strategic 

and non-strategic nuclear systems to threaten the United States, allies, and partners. It may 

mistakenly perceive that these systems, when coupled with the threat of a strategic nuclear 

attack against the United States, would provide advantageous nuclear escalation options in 

crises or conflict.

To address these types of challenges and preserve deterrence stability, the United States 

will enhance the flexibility and range of its tailored deterrence options. U.S. strategy does 

not require non-strategic nuclear capabilities that quantitatively match or mimic Russia’s 

more expansive arsenal. Rather, the 

United States will maintain a 

spectrum of capabilities sized and 

postured to meet U.S. needs, and 

particularly to ensure that no 

adversary under any circumstances 

can perceive an advantage through 

limited nuclear escalation or other 

strategic attack.

For decades, the United States has 

deployed low-yield nuclear options 

to strengthen deterrence and 

assurance. Expanding flexible U.S. 

nuclear options now, to include lowyield options, is important for the 

preservation of credible deterrence against regional aggression. To be clear, this is not 

intended to enable, nor does it enable, “nuclear war-fighting.” Nor will it lower the nuclear 

threshold. Rather, expanding U.S. tailored response options will raise the nuclear 

threshold and help ensure that potential adversaries perceive no possible advantage in 

limited nuclear escalation, making nuclear weapons employment less likely.

Consequently, the United States will maintain, and enhance as necessary, the capability to 

forward deploy nuclear bombers and DCA around the world. We are committed to 

upgrading DCA with the nuclear-capable F-35 aircraft. We will work with NATO to best 

ensure—and improve where needed—the readiness, survivability, and operational 

effectiveness of DCA based in Europe.

Additionally, in the near-term, the United States will modify a small number of existing 

SLBM warheads to provide a low-yield option, and in the longer term, pursue a modern 

nuclear-armed sea-launched cruise missile (SLCM). Unlike DCA, a low-yield SLBM 

warhead and SLCM will not require or rely on host nation support to provide deterrent 

U.S. Air Force F-35A Lightning IIs assigned to Hill Air Force Base, 

Utah taxi at Kunsan Air Base, Republic of Korea, November 27, 2017. 

(U.S. Air Force photo)
55

NUCLEAR POSTURE REVIEW

effect. They will provide additional diversity in platforms, range, and survivability, and a 

valuable hedge against future nuclear “break out” scenarios. 

DoD and NNSA will develop for deployment a low-yield SLBM warhead to ensure a 

prompt response option that is able to penetrate adversary defenses. This is a comparatively 

low-cost and near-term modification to an existing capability that will help counter any 

mistaken perception of an exploitable “gap” in U.S. regional deterrence capabilities. Doing 

so will not increase the number of deployed U.S. ballistic missile warheads, as the lowyield weapons will replace higher-yield weapons currently deployed.

In addition to this near-term step, for the longer term the United States will pursue a 

nuclear-armed SLCM, leveraging existing technologies to help ensure its cost effectiveness. 

SLCM will provide a needed non-strategic regional presence, an assured response 

capability, and an INF-Treaty compliant response to Russia’s continuing Treaty violation. 

If Russia returns to compliance with its arms control obligations, reduces its non-strategic 

nuclear arsenal, and corrects its other destabilizing behaviors, the United States may 

reconsider the pursuit of a SLCM.

Indeed, U.S. pursuit of a SLCM may provide the necessary incentive for Russia to negotiate 

seriously a reduction of its non-strategic nuclear weapons, just as the prior Western 

deployment of intermediate-range nuclear forces in Europe led to the 1987 INF Treaty. As 

then Secretary of State George P. Shultz stated, “If the West did not deploy Pershing II and 

cruise missiles, there would be no incentive for the Soviets to negotiate seriously for nuclear 

weapons reductions.”

In the 2010 NPR, the United States announced the retirement of its previous nuclear-armed 

SLCM, which for decades had contributed to deterrence and the assurance of allies, 

particularly in Asia. Given the increasing need for flexible and low-yield options to 

strengthen deterrence and assurance, we will immediately begin efforts to restore this 

capability by initiating a capabilities study leading to an Analysis of Alternatives (AoA) for 

the rapid development of a modern SLCM. It will strengthen the effectiveness of the seabased nuclear deterrence force and is complementary to LRSO, but cannot substitute for 

it because LRSO is required to sustain an effective air leg of the triad. 

These supplements to the planned nuclear force replacement program--a modified SLBM 

warhead and modern SLCM--are prudent options for enhancing the flexibility and diversity 

of U.S. nuclear capabilities to help address emerging deterrence requirements in the near 

term and beyond. They are compliant with all treaties and agreements, and together, they 

will: provide a more diverse set of characteristics greatly enhancing our ability to tailor 

deterrence and assurance; expand the range of credible U.S. options for responding to 

nuclear or non-nuclear strategic attack; and, enhance deterrence by signaling to potential 

adversaries that their concepts of coercive, limited nuclear escalation offer no exploitable 

advantage. 
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NUCLEAR POSTURE REVIEW

Nuclear Command, Control, and Communications (NC3) 

Modernization

The United States must have an NC3 system that ensures command and control of U.S.

nuclear forces at all times, even under the enormous stress of a nuclear attack. NC3 

capabilities must assure the integrity of transmitted information and possess the resiliency 

and survivability necessary to reliably overcome the effects of adversary nuclear attack. The 

NC3 architecture is essential for deterrence and enables a response if deterrence fails. 

During peacetime and crisis, the NC3 

system performs five crucial functions: 

detection, warning, and attack 

characterization; nuclear planning; 

decision-making conferencing; 

receiving Presidential orders; and 

enabling the management and direction 

of forces.

Today’s NC3 system is a legacy of the 

Cold War, last comprehensively 

updated almost three decades ago. It 

includes interconnected elements 

composed of warning satellites and 

radars;communications satellites, aircraft, and ground stations; fixed and mobile command 

posts; and the control centers for nuclear systems.

› Warning systems include fixed, terrestrial phased array warning radars; the Defense 

Support Program (DSP) system and its replacement, the Space Based Infrared System 

(SBIRS); and the U.S. Nuclear Detonation Detection System (USNDS).

› Communications systems include the Military Strategic and Tactical Relay (MILSTAR)

satellites and its replacement, the Advanced Extremely High Frequency (AEHF) 

satellites; a wide variety of ground-based transmission systems across the radio 

frequency spectrum; and Take Charge and Move Out (TACAMO) relay aircraft.

› The fixed command posts include the National Military Command Center (NMCC) 

and the U.S. Strategic Command Global Operations Center. Fixed command posts

"We have to modernize the entire architecture. And so, as you see the 

modernization plans coming in; make sure, number one, it's the 21st century 

information architecture."

Commander, United States Strategic Command, General John Hyten, 4 April 2017

The Advanced Extremely High Frequency, or AEHF, system 

provides survivable, global, secure, protected and jam-resistant 

communications for high-priority military ground, sea and air 

assets. (U.S. Air Force photo)
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NUCLEAR POSTURE REVIEW

also include linkages to U.S. forward-deployed forces in USEUCOM and elsewhere. 

Mobile command posts include the E4B National Airborne Operations Center 

(NAOC), the E6B Airborne Command Post (ABNCP), and ground mobile systems.

› Control centers for nuclear systems are in ICBM Launch Control Centers, on SSBNs, 

and aboard bomber aircraft.

While once state-of-the-art, the NC3 system is now subject to challenges from both aging 

system components and new, growing 21st century threats. Of particular concern are 

expanding threats in space and cyber space, adversary strategies of limited nuclear 

escalation, and the broad diffusion within DoD of authority and responsibility for 

governance of the NC3 system, a function which, by its nature, must be integrated.

Expanding Threats. Space is no longer a sanctuary and orbital space is increasingly

congested, competitive, and contested. A number of countries, particularly China and 

Russia, have developed the means to disrupt, disable, and destroy U.S. assets in space. 

Because space is no longer an uncontested domain, U.S. NC3 space systems need to be 

more survivable, defendable, and provide resilient capabilities.

The emergence of offensive cyber warfare capabilities has created new challenges and 

potential vulnerabilities for the NC3 system. Potential adversaries are expending 

considerable effort to design and use cyber weapons against networked systems. While our 

NC3 system today remains assured and effective, we are taking steps to address challenges 

to network defense, authentication, data integrity, and secure, assured, and reliable 

information flow across a resilient NC3 network.

Nuclear Environment. Because potential adversaries are emphasizing the employment of 

limited nuclear options, our NC3 system must be resilient in the context of adversary 

limited nuclear strikes. The U.S. leadership, including Combatant Commanders, must be 

able to communicate and share information across networked command and control 

systems, and to integrate nuclear and non-nuclear military planning and operations in the 

context of adversary nuclear employment.

Modernizing the NC3 System

In light of the critical need to ensure our NC3 system remains survivable and effective in 

crisis and conflict, the United States will pursue a series of initiatives to strengthen NC3 

and address 21st century needs and challenges.

Strengthen Protection Against Space-based Threats. The United States will ensure space 

assets are agile and resilient, thereby deterring and if necessary overcoming attempts to 

extend conflict into space. The United States will enhance the training of operational space 

forces to ensure that we are prepared to successfully achieve mission objectives against the 

range of 21st century threats.
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NUCLEAR POSTURE REVIEW

Strengthen Protection Against Cyber Threats. The United States will protect NC3

components against current and future cyber threats and ensure the continuing availability 

of U.S.-produced information technology necessary for the NC3 system.

Enhance Integrated Tactical Warning and Attack Assessment. The United States will 

develop a future architecture which will include modernized SBIRS satellites and integrate 

missile defense sensors to maximize warning time. The United States will also continue to 

transition the DSP system to SBIRS and enhance ground-based radars. The upgraded SBIRS 

constellation will include six satellites supported by the existing DSP architecture to 

enhance the survivability of U.S. satellites. Additionally, we will continue to sustain and 

upgrade the USNDS to support accurate attack assessment.

Improve Command Posts and Communications Links. The United States will upgrade and 

modernize critical NC3 airborne systems, including the NAOC, the ABNCP, and the 

TACAMO aircraft. We will also develop planning systems at all fixed and mobile sites to 

enhance command and control, and 

field modernized communication 

transmitters and terminals across the 

NC3 system to better ensure assured, 

reliable, and resilient communications 

at all levels of the nuclear force.

Advance Decision Support Technology. 

The United States will continue to 

adapt new technologies for information 

display and data analysis to improve 

support for Presidential decision 

making and senior leadership 

consultations.

Integrate Planning and Operations. The 

United States will improve the capability of our Combatant Commands to communicate 

and share information across networked command and control systems in the context of 

adversary nuclear employment. U.S. forces will strengthen their ability to integrate 

nuclear and non-nuclear military operations to deter limited nuclear escalation and nonnuclear strategic attacks. Finally, Combatant Commands will plan, organize, train, and 

exercise for this mission.

Reform Governance of the Overall NC3 System. The United States will improve its NC3 

governance to ensure DoD is properly organized to maintain a fully capable NC3 system to 

address current and future environments. To address this challenge, the Chairman of the 

Joint Chiefs of Staff in consultation with key DoD stakeholders will deliver to the Secretary 

of Defense no later than May 1, 2018, a plan to reform NC3 governance to ensure its 

effective functioning and modernization.

Missile Technician 3rd Class, Senior Chief Missile Technician and 

Machinist's Mate, all assigned to the Ohio-class ballistic-missile 

submarine USS Alaska (SSBN 732), operate the controls of the 

dive simulator at the Trident Training Facility. (U.S. Navy photo)
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NUCLEAR POSTURE REVIEW

VIII. Nuclear Weapons 

Infrastructure

“NNSA’s ability to achieve its vital national security missions is 

dependent on safe and reliable infrastructure. If not appropriately 

addressed, the age and condition of NNSA’s infrastructure will put 

NNSA’s missions, safety of its workers, the public, and the 

environment at risk.”

NNSA Administrator, Frank Klotz, 2017
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NUCLEAR POSTURE REVIEW

VIII. Nuclear Weapons infrastructure

An effective, responsive, and resilient nuclear weapons infrastructure is essential to the 

U.S. capacity to adapt flexibly to shifting requirements. Such an infrastructure offers 

tangible evidence to both allies and potential adversaries of U.S. nuclear weapons 

capabilities and can help to deter, assure, hedge against adverse developments, and 

discourage adversary interest in arms competition.

The NNSA is responsible for the Nation’s nuclear weapons infrastructure. DoD generates 

military requirements for the nuclear warheads to be carried on delivery platforms. The 

NNSA oversees the assessment, design development, production, test, and research 

programs that respond to DoD warhead requirements.

The infrastructure consists of people with the requisite skills (e.g., scientists, engineers, 

production personnel) and the associated experimental and industrial facilities that:

› Sustain today’s nuclear stockpile and ensure its continued safety, security, and 

effectiveness;

› Extend the life of a select sub-set of nuclear warheads, and design, develop, and 

produce nuclear weapons as needed for today and into the future;

› Assess and certify annually whether the safety and reliability of the future nuclear 

stockpile can be assured in the absence of underground nuclear testing, and, as a 

safeguard, maintain a nuclear test capability;

› Maintain the capability to design, develop and produce nuclear warheads with new or 

different military capabilities if required in the future; and

› Provide an effective response to technical problems with a warhead or to adverse 

geopolitical developments that call for force augmentation.

In addition, the scientists, engineers, and production personnel of the nuclear infrastructure 

support nuclear arms control, threat reduction, naval nuclear propulsion, non-proliferation 

efforts, assessment of foreign nuclear 

weapons programs, nuclear 

counterterrorism, and emergency 

response.

The main challenge to an effective

and resilient infrastructure is the 

need to maintain design,

development, manufacturing, and 

testing capabilities during the 

lengthy periods of time between 

rebuilding cycles to ensure the 

enduring health of the infrastructure. 

During the Cold War, the United 

States carried out an intensive and 

Machinists at Lawrence Livermore National Laboratory use a state-ofthe-art hydraulic press needed for W80-4 work. (Photo provided by 

NNSA)
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NUCLEAR POSTURE REVIEW

balanced program on roughly a five-year cycle. The last new, modern warhead 

development program (the W88) was completed by the early 1990s. 

We are now in the early stages of a comprehensive warhead sustainment program. To 

provide the required strategic vision needed to inform critical warhead modernization 

investments, the DoD and DOE Nuclear Weapons Council approved a strategic plan. This 

plan describes a current and future path for the nuclear warhead stockpile to meet 

deterrence, assurance, and technical hedging requirements.

The U.S. must have the ability to maintain and certify a safe, secure, and effective nuclear 

arsenal. Synchronized with DoD replacement programs, the United States will sustain and 

deliver on-time the warheads needed to support both strategic and non-strategic nuclear 

capabilities by:

› Completing the W76-1 LEP by Fiscal Year (FY) 2019;

› Completing the B61-12 LEP by FY2024;

› Completing the W88 alterations by FY2024;

› Synchronizing NNSA’s W80-4 life extension, with DoD’s LRSO program and 

completing the W80-4 LEP by FY2031;

› Advancing the W78 warhead replacement one year to FY19 to support fielding on 

GBSD by 2030 and investigate the feasibility of fielding the nuclear explosive package 

in a Navy flight vehicle;

› Sustaining the B83-1 past its currently planned retirement date until a suitable 

replacement is identified; and,

› Exploring future ballistic missile warhead requirements based on the threats and 

vulnerabilities of potential adversaries, including the possibility of common reentry 

systems between Air Force and Navy systems.

Over the past several decades, the 

U.S. nuclear weapons infrastructure 

has suffered the effects of aging and 

underfunding. Over half of NNSA’s 

infrastructure is over 40 years old, 

and a quarter dates back to the 

Manhattan Project era. All previous 

NPRs highlighted the need to 

maintain a modern nuclear weapons 

infrastructure, but the United States 

has fallen short in sustaining a modern 

infrastructure that is resilient and has 

the capacity to respond to unforeseen 

developments. There is now no Detector for Advanced Neutron Capture Experiments at Los Alamos 

Neutron Science Center. (Photo provided by NNSA)
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NUCLEAR POSTURE REVIEW

margin for further delay in recapitalizing the physical infrastructure needed to produce 

strategic materials and components for U.S. nuclear weapons.

In 2008, the Secretary of Defense and Secretary of Energy released a joint report stating, 

“While the service lives of existing warhead types are being extended through 

refurbishment, at present the United States does not have the ability to produce new 

nuclear weapons.” While North Korea can illicitly produce nuclear warheads, the United 

States does not have a sustained plutonium pit manufacturing capability needed to avoid 

stockpile age-out, support life extension programs, and prepare for future uncertainty. 

Plutonium pits are critical components of every nuclear warhead, with nearly all current 

stockpile pits having been produced from 1978—1989. Today, the U.S. capability to 

produce plutonium pits is limited to research and development pits unsuitable for stockpile 

use. To avoid age-related risks, DoD requires NNSA to produce at least 80 plutonium pits 

per year by 2030, and to sustain the capacity for future LEPs and follow-on programs.

U.S. production of tritium, a critical strategic material for nuclear weapons, is now 

insufficient to meet the forthcoming U.S. nuclear force sustainment demands, or to hedge 

against unforeseen developments. Programs are planned, but not yet fully funded, to ease 

these critical production shortfalls. In the absence of sustained support for these programs, 

including a marked increase in the planned production of tritium in the next few years, our 

nuclear capabilities will inevitably atrophy and degrade below requirements.

The U.S. is also unable to produce or process a number of other critical materials, including 

lithium and enriched uranium. For instance, the United States largely relies on dismantling 

retired warheads to recover lithium to sustain and produce deployable warheads. This may 

be inadequate to support the nuclear force replacement program and any supplements to 

it.

Past assumptions that our capability 

to produce nuclear weapons would 

not be necessary and that we could 

permit the required infrastructure to 

age into obsolescence have proven to 

be mistaken. It is now clear that the 

United States must have sufficient 

research, design, development, and 

production capacity to support the 

sustainment and replacement of its 

nuclear forces. To meet these needs, 

the United States must resolve the 

current significant infrastructure 

funding shortfalls over the next five 

years.

Secretary Perry meets with Yukiya Amano, Director General of IAEA 

on March 20, 2017 at the Department of Energy. (Photo provided by 

DOE)
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NUCLEAR POSTURE REVIEW

To remain postured to address challenges that may emerge, the United States needs the 

flexibility to hedge against future risks. Consequently, NNSA will explore approaches for 

rapid prototyping, develop options for modifying warheads to increase flexibility and 

responsiveness, examine the potential for retired warheads and components to augment 

the future hedge stockpile, and survey past and extant warhead designs to better understand 

what can be certified without resuming full-scale nuclear testing. An additional measure 

for needed flexibility is to reduce the time required to design, develop,and initially produce 

a warhead, from a decision to enter full-scale development.

Along with its nuclear weapon development and production infrastructure, NNSA will 

maintain the capability to resume underground nuclear explosive testing if called upon to 

do so. The United States will not seek Senate ratification of the Comprehensive Nuclear 

Test Ban Treaty, but willcontinue to observe a nuclear test moratorium that began in 1992. 

This posture was adopted with the understanding that the United States must remain ready 

to resume nuclear testing if necessary to meet severe technological or geopolitical 

challenges.

The nuclear weapons infrastructure depends on a highly skilled, world-class workforce 

from a broad array of disciplines, including engineering, physical sciences, mathematics,

and computer science. Maintaining the necessary critical skills and retaining personnel with 

the needed expertise requires sufficient opportunities to exercise those skills. Should a 

technical or geopolitical development demand a new nuclear weapon, it is crucial that the 

nuclear weapons workforce possess the skills and the knowledge needed to design, develop, 

and manufacture warheads of different design in a timely manner.

Yet, the United States, unlike potential adversaries, has not executed a new nuclear weapon 

program for decades. Ongoing work involves life extension programs for existing 

weapons. To ensure we sustain the necessary skills and knowledge required to take new 

warhead designs from initial concept through development, prototyping, and plans for 

certification, NNSA should assess capabilities currently being exercised by: life extension 

programs, stockpile certification, laboratory directed research and development, and 

technology maturation. On this basis, NNSA will identify any gaps in the full range of the 

skills needed to design and develop nuclear weapons. The Stockpile Responsiveness 

Program that Congress recently instituted with bipartisan support explicitly directs that the 

United States ensure the responsiveness and flexibility of our nuclear weapons 

infrastructure. This is an important element of the U.S. hedging strategy because it 

promises to provide more timely availability of new capabilities if they are needed to meet 

changes in the security environment.

The United States will pursue initiatives to ensure the necessary capability, capacity, and 

responsiveness of the nuclear weapons infrastructure and the needed skills of the nuclear 

enterprise workforce, including the following:
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› Pursue a joint DoD and DOE advanced-technology development capability to ensure 

that efforts are appropriately integrated to meet DoD needs.

› Provide the enduring capability and capacity to produce plutonium pits at a rate of no 

fewer than 80 pits per year by 2030. A delay in this would result in the need for a 

higher rate of pit production at higher cost.

› Ensure that current plans to reconstitute the U.S. capability to produce lithium 

compounds are sufficient to meet military requirements.

› Fully fund the Uranium Processing Facility and ensure availability of sufficient lowenriched uranium to meet military requirements.

› Ensure the necessary reactor capacity to produce an adequate supply of tritium to 

meet military requirements.

› Ensure continuity in the U.S. capability to develop and manufacture secure, trusted 

strategic radiation-hardened microelectronic systems beyond 2025 to support 

stockpile modernization.

› Rapidly pursue the Stockpile Responsiveness Program established by Congress to 

expand opportunities for young scientists and engineers to advance warhead design, 

development, and production skills.

› Develop an NNSA roadmap that sizes production capacity to modernization and 

hedging requirements.

› Retain confidence in nuclear gravity bombs needed to meet deterrence needs.

› Maintain and enhance the computational, experimental, and testing capabilities 

needed to annually assess nuclear weapons.

Due to underfunding by previous administrations, significant and sustained investments will 

be required over the coming decade to ensure that NNSA will be able to deliver the nuclear 

weapons at the needed rate to support nuclear deterrence in the 2030s and beyond.
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IX. Countering 

Nuclear Terrorism 

“[W]e must prevent nuclear weapons and materials from 

coming into the hands of terrorists and being used against us, 

or anywhere in the world...”

President Donald Trump, August 21, 2017
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IX. Countering nuclear terrorism

Nuclear terrorism remains among 

the most significant threats to the 

security of the United States, allies, 

and partners. The Joint Chiefs of 

Staff, in 2015, emphasized, 

“Nuclear, chemical, and biological 

agents pose uniquely destructive 

threats. They can empower a small 

group of actors with terrible 

destructive potential. Thus 

combatting weapons of mass 

destruction (WMD) as far from our 

homeland as possible is a key mission 

for the U.S. military.”

U.S. strategy to combat the threat of 

nuclear terrorism encompasses a wide range of activities that comprise a defense-in-depth 

against current and emerging dangers. Under this multilayered approach, the United States 

strives to prevent terrorists from obtaining nuclear weapons or weapons-usable materials, 

technology, and expertise; counter terrorist efforts to acquire, transfer, or employ these 

assets; and respond to nuclear incidents, by locating and disabling a nuclear device or 

managing the consequences of a nuclear detonation. Key U.S. efforts under this strategy 

include:

› Securing nuclear weapons, materials, related technology, and knowledge to prevent 

their malicious use.

› Enhancing cooperation with allies, partners, and international institutions to combat 

nuclear terrorism.

› Deterring state support for nuclear terrorism through advanced forensics and 

attribution capabilities.

› Strengthening defenses against nuclear terrorism to protect the American people and 

U.S. interests at home and abroad.

› Enhancing preparedness to mitigate the effects of nuclear incidents.

With the cooperation of overseas partners, the United States has worked for nearly three

decades to keep nuclear and radiological materials out of the hands of terrorists. As the 

number of nuclear facilities and the quantity of nuclear material worldwide continue to 

increase, we will maintain our focus on reducing the vulnerability of these materials to theft 

or seizure. We will also decrease the availability of sensitive equipment and technologies 

on the black market and thereby hinder terrorist access to them.

U.S. Airmen from the 193rd Special Operations Squadron, prepare to 

board an EC-130J Commando Solo aircraft December 2, 2017, at 

193rd Special Operations Wing, Middletown, Pennsylvania. (U.S. Air 

National Guard photo)
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NUCLEAR POSTURE REVIEW

The most effective way to reduce 

the risk of nuclear terrorism is to 

secure nuclear weapons and 

materials at their sources. The 

United States will continue to 

work with allies and partners to 

disrupt proliferation networks and 

interdict transfers of nuclear 

materials and related technology. 

In particular, we will improve 

coordination with international 

export-control and lawenforcement agencies to bolster 

information sharing to detect and 

interdict nuclear and radiological 

material. Through collaboration with foreign partners, we will maintain the constellation 

of radiation detection technologies that have been deployed in 60 countries around the 

world to thwart the smuggling of nuclear weapons and materials by land, sea, and air. 

Domestically, we will sustain and build upon the roughly 57,000 radiation detectors 

operating at U.S. seaports, border crossings, and within the American interior.

As part of this defense-in-depth, the United States will sustain its specialized capabilities to 

search for, interdict, characterize, and disable nuclear devices. These assets are strategically 

pre-positioned throughout the country to respond rapidly to nuclear incidents and save 

American lives. Should an act of nuclear terrorism occur, the United States also maintains 

advanced nuclear forensics capabilities to identify the source of the material used in a 

nuclear device, thereby strengthening the deterrence of such an attack. We will continue 

to improve our ability to attribute 

the source of a nuclear attack by 

establishing a nuclear materials 

archive to store, consolidate, and 

analyze high-value nuclear 

materials.

The United States will hold fully 

accountable any state, terrorist

group, or other non-state actor that 

supports or enables terrorist efforts 

to obtain or employ nuclear 

devices. Although the role of U.S. 

nuclear weapons in countering 

nuclear terrorism is limited, for 

effective deterrence our 

Participants in Prominent Hunt 17-2, an interagency Nuclear Forensics 

Exercise, held in New Mexico. (Photo provided by NNSA)

Soldiers from the Hawaii National Guard's 93rd Weapons of Mass 

Destruction Civil Support Team receive hands-on training with the Talon 

IV unmanned robot at the Robot Logistics Support Center, in Lexington, 

Ky., July 26, 2017. (Army photo)
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adversaries must understand that a terrorist nuclear attack against the United States or its 

allies and partners would qualify as an “extreme circumstance” under which the United 

States could consider the ultimate form of retaliation.
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X. Non-proliferation 

and Arms Control

“In a world with no overarching global authority, rules are only 

as strong as the willingness of states to follow or enforce them.”

Joint Chiefs of Staff, 2016
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X. non-proliferation and arms control

Effective nuclear non-proliferation and arms control measures can support U.S., allied, and 

partner security by controlling the spread of nuclear materials and technology; placing 

limits on the production, stockpiling, and deployment of nuclear weapons; decreasing 

misperception and miscalculation; and avoiding destabilizing nuclear arms competition. 

Consequently, the United States will continue its efforts to: 1) minimize the number of 

nuclear-armed states, including by maintaining credible U.S. extended nuclear deterrence 

and assurance; 2) deny terrorist organizations access to nuclear weapons, materials, and 

expertise; 3) strictly control weapons-usable material, related technology, and expertise; 

and 4) seek arms control agreements that enhance security, and are verifiable and 

enforceable.

Non-Proliferation and the Nuclear 

Non-Proliferation Treaty

The NPT is the cornerstone of the nuclear non-proliferation regime. It provides the formal 

international legal framework for measures to constrain and deny proliferators and to 

identify, contain, and sanction 

transgressors. The Treaty 

establishes a framework governing 

peaceful uses of nuclear energy, 

allowing states to pursue civil 

nuclear programs under safeguards 

that help provide transparency and 

confidence that such programs will 

not contribute to proliferation. The 

NPT’s positive role in building 

consensus for non-proliferation 

enhances international efforts to 

impose costs on those who would 

pursue nuclear weapons outside the 

Treaty. It also contributes to U.S. 

and international efforts to mitigate threats of nuclear terrorism by helping to safeguard 

nuclear and radiological material and prevent the spread of sensitive nuclear technologies 

and expertise.

The United States remains committed to nuclear non-proliferation, continues to abide by 

its obligations under the NPT, and will work to strengthen the NPT regime. In addition, 

the United States will continue to maintain a credible nuclear umbrella extended to over 

thirty allies and partners. This is essential to meeting their need for nuclear deterrence, 

while enabling them to forego independent nuclear weapons capabilities. Credible U.S. 

extended nuclear deterrence will continue to be a cornerstone of U.S. non-proliferation 

efforts.

NNSA and the Institute of Nuclear Physics in Kazakhstan collaborate 

to remove all HEU from the institute’s reactor. (Photo provided by 

NNSA)
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Nuclear non-proliferation today faces acute challenges. Most significantly, North Korea is 

pursuing a nuclear path in direct contravention of the NPT and in direct opposition to 

numerous U.N. Security Council resolutions. The risk of North Korea employing nuclear 

weapons or attempting to sell its nuclear technology and expertise is an international 

problem and the international community must continue to work toward preventing this 

threat.

Beyond North Korea looms the challenge of Iran. Although the JCPOA may constrain 

Tehran’s nuclear program, Iran retains the ability to produce weapons grade uranium for 

use in a nuclear weapon if it decides to do so. This, combined with Iran’s ongoing missile 

testing, is a serious concern.

Despite these challenges, the institutions that support the NPT, such as the International 

Atomic Energy Agency, help identify violations, provide evidentiary support for the 

imposition of multilateral sanctions, and, as is the case with Iran, establish international 

monitoring and verification capabilities. Perhaps most importantly, strengthening these 

institutions and the international safeguards system supports verifiable, durable progress on 

non-proliferation and potentially further negotiations on nuclear reductions if the security 

environment permits.

In continuing support of nuclear nonproliferation, the United States will 

continue to pursue the political and 

security conditions that could enable 

further nuclear reductions. We will 

work to increase transparency and 

predictability, where appropriate, to 

avoid potential miscalculation among 

nuclear weapons states and other 

possessor states through strategic 

dialogues, risk-reduction 

communications channels, and 

sharing of best practices related to 

nuclear weapons safety and security.

To further strengthen the NPT 

regime, the United States will support 

initiatives to improve capabilities to 

detect, deter, and attribute proliferation and use; reduce the vulnerability of nuclear and 

radiological materials to theft or seizure around the world; and reduce the availability of 

proliferation-sensitive equipment and technologies through illicit transfers. These activities 

will reduce potential terrorist access to this equipment and technology. The United States 

will also support the efforts of multilateral supplier regimes such as the Zangger Committee 

and the Nuclear Suppliers Group. We will continue to perfect forensics capabilities for 

Arizona Army National Guard Soldiers from the 2220th 

Transportation Company are engulfed by colored smoke after 

putting on their protective masks during a simulated chemical attack 

August 5, 2017 at Florence Military Reservation in Florence, Ariz. 

The Guardsmen conducted nuclear, biological and chemical warfare 

training which included entering a gas chamber and being exposed to 

CS tear gas. (U.S. Army National Guard photo)
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NUCLEAR POSTURE REVIEW

attribution purposes by establishing a nuclear materials archive to store, consolidate, and 

analyze high-value nuclear materials to work in concert with the existing Nuclear Materials 

Information Program.

Further, the United States remains committed to finding long-term solutions to the 

technical challenges of verifying nuclear reductions, and therefore will explore new 

concepts and approaches for this goal, including continued support for the International 

Partnership for Nuclear Disarmament Verification.

The number of nuclear facilities and the quantities of nuclear materials worldwide continue 

to increase, with a wide variance in security measures and potential vulnerabilities that 

could result in terrorist acquisition of nuclear materials. Consequently, the United States 

will continue to work with allies and partners to disrupt proliferation networks; interdict 

transfers of WMD-related materials, technology, and expertise; prevent the employment 

of improvised nuclear devices; attribute responsibility to perpetrators; and mitigate the 

consequences of WMD employment.

Although the United States will not seek Senate ratification of the Comprehensive Nuclear 

Test Ban Treaty, it will continue to support the Comprehensive Nuclear Test Ban Treaty 

Organization Preparatory Committee as well as the related International Monitoring 

System and the International Data Center, which detect nuclear tests and monitor seismic 

activity. The United States will not resume nuclear explosive testing unless necessary to 

ensure the safety and effectiveness of the U.S. nuclear arsenal, and calls on all states 

possessing nuclear weapons to declare or maintain a moratorium on nuclear testing.

Finally, it is important to recognize that the Nuclear Weapons Ban Treaty, opened for 

signature at the U.N. in 2017, is fueled by wholly unrealistic expectations of the elimination 

of nuclear arsenals without the prerequisite transformation of the international security 

environment. This effort has polarized the international community and seeks to inject 

disarmament issues into non-proliferation fora, potentially damaging the non-proliferation 

regime. This Treaty could damage U.S. security and the security of many allies and partners 

who rely on U.S. extended nuclear deterrence. The terms of the Nuclear Weapons Ban 

Treaty also could undermine ongoing and prospective military cooperation between the 

United States and signatory states, cooperation that is critical to the maintenance of credible 

extended nuclear deterrence.

Arms Control

Arms control can contribute to U.S., allied, and partner security by helping to manage 

strategic competition among states. By codifying mutually agreed-upon nuclear postures 

in a verifiable and enforceable manner, arms control can help establish a useful degree of 

cooperation and confidence among states. It can foster transparency, understanding, and 

predictability in adversary relations, thereby reducing the risk of misunderstanding and 
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miscalculation. In addition to formal 

agreements, regular dialogues on 

doctrine and forces can also 

contribute to mutual understanding 

and reduce the risk of miscalculation.

In a series of Cold War arms control 

agreements, for example, the United 

States and Soviet Union increased 

transparency, moderated 

competition, codified rough parity in 

strategic nuclear arms, and closed off 

areas of competition. The most 

recent 2010 New START Treaty 

caps accountable U.S. and Russian strategic force levels, and includes some intrusive 

verification measures to help monitor compliance.

New START is in effect through February 2021 and with mutual agreement, may be 

extended for up to five years, to 2026. The United States has already met the Treaty’s 

central limits which go into force on February 5, 2018, and will continue to implement the 

New START Treaty and verify Russian compliance.

Progress in arms control is not an end in and of itself, and depends on the security 

environment and the participation of willing partners. The United States is committed to 

arms control efforts that advance U.S., allied, and partner security; are verifiable and 

enforceable; and include partners that comply responsibly with their obligations. Such arms 

control efforts can contribute to the U.S. capability to sustain strategic stability. Further 

progress is difficult to envision, however, in an environment that is characterized by 

nuclear-armed states seeking to 

change borders and overturn existing 

norms, and by significant, continuing 

non-compliance with existing arms 

control obligations and 

commitments.

In this regard, Russia continues to 

violate a series of arms control 

treaties and commitments, the most 

significant being the INF Treaty. In a 

broader context, Russia is either 

rejecting or avoiding its obligations 

and commitments under numerous 

agreements, including the Conventional Armed Forces in Europe Treaty, the Budapest 

Memorandum, the Helsinki Accords, and the Presidential Nuclear Initiatives. In addition, 

(State Department – Open Skies) 

Members of the technical team make adjustments during a reactor 

conversion in Ghana. (Photo provided by NNSA)
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NUCLEAR POSTURE REVIEW

Russia has violated the Open Skies Treaty and is selectively implementing the politically 

binding Vienna Document to avoid transparency of its major military exercises. Russia has 

also rebuffed U.S. efforts to follow New START with another round of negotiated 

reductions, and to pursue reductions in non-strategic nuclear forces.

Regarding the INF Treaty, the United States complies with and remains committed to 

preserving the Treaty. However, the value of the INF Treaty, or any arms control treaty, 

depends on all parties remaining in compliance. For over four years, the United States has 

pressed Russia to return to compliance, and will continue to exert appropriate pressure to 

restore Russian compliance and preserve the INF Treaty.

Nevertheless, Moscow must understand that the United States will not forever endure 

Russia’s continuing non-compliance. The status quo, in which the United States continues 

to comply while Russia continues deployments in violation of the Treaty, is untenable. 

Agreements that are violated cannot 

provide predictability; undermine 

the prospects for future arms 

control; and can harm U.S., allied, 

and partner security. Concluding 

further agreements with a state in 

violation of multiple existing 

agreements would indicate a lack of 

consequences for its non-compliance 

and thereby undermine arms control 

broadly.

Consequently, the United States will 

work to convince states in violation 

of their legal arms control 

obligations to return to compliance. Arms control efforts must now emphasize confidence 

and security building measures to rebuild trust and communication. The United States 

seeks to reestablish the conditions necessary for greater trust with Russia and improved 

transparency with China as it expands and modernizes its nuclear forces. 

The United States remains willing to engage in a prudent arms control agenda. We are 

prepared to consider arms control opportunities that return parties to predictability and 

transparency, and remain receptive to future arms control negotiations if conditions permit 

and the potential outcome improves the security of the United States and its allies and 

partners.

Air Force Master Sergeant calls range commands during a live-fire 

exercise at Fort Carson, Colo., June 9, 2017. He is the first sergeant 

assigned to the 233rd Support Group. (Air National Guard photo)
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