2018
REVIEW

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NUCLEAR POSTURE REVIEWFEBRUARY 2018

OFFICE OF THE SECRETARY OF DEFENSEREVIEW

This page left intentionally blankCONTENTS
SECRETARY’S PREFACE ......................................................................IEXECUTIVE SUMMARY ......................................................................VIntroduction ............................................................................................................. 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 ........................................... XIEnhancing Deterrence with Non-strategic Nuclear Capabilities............................................... XI
Nuclear Command, Control, and Communications Modernization ......................................... XIII
Nuclear Weapons Infrastructure.................................................................................. XIVCountering 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

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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

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 numberof nuclear weapons. The 1991 Strategic Arms Reduction Treaty (START) set aceiling 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 andcapabilities that rely on nuclear escalation for their success. These developments,
coupled with Russia’s seizure of Crimea and nuclear threats against our allies, markMoscow’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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NUCLEAR POSTURE REVIEW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 theuncertainties regarding the future security environment.
Given the range of potential adversaries, their capabilities and strategic objectives,
this review calls for a flexible, tailored nuclear deterrent strategy. This review calls forthe 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 mostextreme 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 andpreserving peace. Our goal is to convince adversaries they have nothing to gain andeverything 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 themost cost-effective and strategically sound means of ensuring nuclear deterrence. The
triad provides the President flexibility while guarding against technological surpriseor sudden changes in the geopolitical environment. To remain effective, however, wemust 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 themodernization 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 ourdual-capable fighter bombers with next-generation F-35 fighter aircraft will maintainthe 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 longpast due; it is vital we ensure the capability to design, produce, assess, and maintainthese weapons for as long as they are required. Due to consistent underfunding,significant and sustained investments will be required over the coming decade toensure that National Nuclear Security Administration will be able to deliver theII
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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 areapproximately three percent of the annual defense budget. Additional funding ofanother three to four percent, over more than a decade, will be required to replacethese aging systems. This is a top priority of the Department of Defense. We aremindful of the sustained financial commitment and gratefully recognize the ongoingsupport of the American people and the United States Congress for this importantmission.
While we will be relentless in ensuring our nuclear capabilities are effective, theUnited 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 playa 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 readynuclear 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 themen 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 agrateful and safe Nation.

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NUCLEAR POSTURE REVIEW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 emphasizedboth the long-term goal of eliminating nuclear weapons and the requirement that theUnited States have modern, flexible, and resilient nuclear capabilities that are safe andsecure 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 haveworsened 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 weaponsand 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 salienceof 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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NUCLEAR POSTURE REVIEW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 andreplacement of U.S. nuclear forces. This 2018 NPR assesses previous nuclear policies
and requirements that were established amid a more benign nuclear environment andmore 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 andseeks stable relations with both. We have long sought a dialogue with China to enhance
our understanding of our respective nuclear policies, doctrine, and capabilities; toimprove 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 occupationof Crimea, this constructive engagement has declined substantially. We look forward
to conditions that would once again allow for transparent and constructive engagementwith 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 toprotect 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 arenecessary 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 doso. 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 failuresof 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 theirsecurity, which correspondingly is also key to non-proliferation.
U.S. Nuclear Capabilities andEnduring 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 forcesmust be assessed against each role and the strategy designed to fulfill it. Preventing
proliferation and denying terrorists access to finished weapons, material, or expertiseare 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 ofnuclear 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 andcontexts: 1) the United States is able to identify them and hold them accountable foracts 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, andwill 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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NUCLEAR POSTURE REVIEW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 UnitedStates 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 failto 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 thismission, 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 UnitedStates 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 thestrength 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 ontheir 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 thelowest 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 thisobjective of limiting damage if deterrence fails.
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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. 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 theincreasing prominence of nuclear weapons in potential adversaries’ defense policies andstrategies, 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 theUnited States Armed Forces and civilian personnel who dedicate their professional lives
to the deterrence of war and protecting the Nation. These exceptional men and womenare 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 withlittle 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 haveaccordingly implemented were long overdue, and the Department of Defense remains
fully committed to properly supporting the Service members who protect the UnitedStates 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, andhedging.

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NUCLEAR POSTURE REVIEWThe increasing need for this diversity and flexibility, in turn, is one of the primaryreasons why sustaining and replacing the nuclear triad and non-strategic nuclear
capabilities, and modernizing NC3, is necessary now. The triad’s synergy andoverlapping 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 easeadversary 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 takethe steps needed to ensure that OHIO SSBNs remain operationally effective andsurvivable 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 inunderground silos and dispersed across several states. The United States has initiatedthe Ground-Based Strategic Deterrent (GBSD) program to begin the replacement of
Minuteman III in 2029. The GBSD program will also modernize the 450 ICBM launchfacilities 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, andeventually 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 numberof 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 theX
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ongoing life extension program for the B61 bomb, it will be a key contributor tocontinued 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 priorityof 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 andreplace U.S. nuclear capabilities vary, even the highest of these projections place thehighpoint 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 areflection 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 thethreshold for Moscow’s first-use of nuclear weapons. Russia demonstrates its
perception of the advantage these systems provide through numerous exercises andstatements. 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, thisis 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 andhelp 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 tobest 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, anda 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 ofan exploitable “gap” in U.S. regional deterrence capabilities.
In addition to this near-term step, for the longer term the United States will pursue anuclear-armed SLCM, leveraging existing technologies to help ensure its costeffectiveness. 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 ofallies, 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 arecompliant with all treaties and agreements, and together, they will: provide a diverse
set of characteristics enhancing our ability to tailor deterrence and assurance; expand therange 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 forcesat all times, even under the enormous stress of a nuclear attack. NC3 capabilities mustassure the integrity of transmitted information and possess the resiliency andsurvivability 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 directionof 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 forgovernance 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 planningand 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 theeffects 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 theUnited States has fallen short in sustaining a modern infrastructure that is resilient andhas the capacity to respond to unforeseen developments. There now is no margin forfurther delay in recapitalizing the physical infrastructure needed to produce strategic
materials and components for U.S. nuclear weapons. Just as our nuclear forces are anaffordable 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 andcompleting 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 suitablereplacement is identified; and,XIV
NUCLEAR POSTURE REVIEW›Exploring future ballistic missile warhead requirements based on the threats andvulnerabilities 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, andresponsiveness of the nuclear weapons infrastructure and the needed skills of theworkforce, 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 needfor a higher rate of pit production at higher cost.

›

Ensure that current plans to reconstitute the U.S. capability to produce lithiumcompounds 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 tomeet military requirements.

›

Ensure continuity in the U.S. capability to develop and manufacture secure,trusted strategic radiation-hardened microelectronic systems beyond 2025 tosupport 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 andhedging 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 thismultilayered approach, the United States strives to prevent terrorists from obtaining
nuclear weapons or weapons-usable materials, technology, and expertise; counter theirefforts to acquire, transfer, or employ these assets; and respond to nuclear incidents, by

XV
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, terroristgroup, 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 ofnuclear weapons states, including by maintaining credible U.S. extended nuclear
deterrence and assurance; 2) deny terrorist organizations access to nuclear weapons andmaterials; 3) strictly control weapons-usable material, related technology, andexpertise; 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-proliferationand 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 toincrease transparency and predictability, where appropriate, to avoid potential
miscalculation among nuclear weapons states and other possessor states throughstrategic dialogues, risk-reduction communications channels, and the sharing of bestpractices related to nuclear weapons safety and security.

XVI
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 Systemand 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, andpartner 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 withexisting arms control obligations and commitments, and by potential adversaries whoseek to change borders and overturn existing norms.
In this regard, Russia continues to violate a series of arms control treaties andcommitments. In the nuclear context, the most significant Russian violation involves asystem 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 willcontinue to implement the New START Treaty.
The United States remains willing to engage in a prudent arms control agenda. We areprepared 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 theUnited States, its allies, and partners.

XVII
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

1
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 boththe long-term goal of eliminating nuclear weapons and the requirement that the UnitedStates have modern, flexible,
andresilientnuclearcapabilities that are safe,
secure, and effective until sucha time as nuclear weapons canprudently be eliminated fromthe world.
The United States remains
committed to its efforts insupport of the ultimate global
eliminationofnuclear,biological, and chemical
weapons. It has negotiated The Ohio-class ballistic missile submarine USS Nebraska (SSBN 739)
multiple arms control treaties transits into open ocean during an underway for training and
Nebraska is one of eight ballistic missile submarinesand has fully abided by its treaty proficiency.
stationed at Naval Base Kitsap-Bangor and recently completed ancommitments. In addition, for extended major maintenance period, including an engineered
overhaul, at Puget Sound Naval Shipyard and Intermediateover two decades the United refueling
Maintenance Facility. (U.S. Navy photo)
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 safeguardinternational 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 theinternational norms and order we have worked with our allies, partners, and membersof the international community to build and sustain. Some regions are marked bypersistent disorder that appears likely to continue and possibly intensify. Thesedevelopments 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 notransparency into its intentions. North Korea continues its illicit pursuit of nuclear
2
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 inouter 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 ina 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 theinfrastructure needed to support them. Consequently, the United States has initiated aseries of programs to sustain and replace existing nuclear capabilities before they reachthe end of their service lives. These programs are critical to preserving our ability todeter threats to the Nation.

3
NUCLEAR POSTURE REVIEWThis page left intentionally blank

4
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 haveadvanced 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

5
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 andconnected challenges—contested norms and persistent disorder.” The rapid deteriorationof the threat environment since the 2010 NPR must now shape our thinking as weformulate 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 natureof 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, haddeclined and would continue to decline dramatically.

›

The United States could decrease incentives for nuclear proliferation globally andreduce the likelihood of nuclear weapons employment by reducing both the role ofnuclear 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 theUnited 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 Warinternational 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 andpolitical commitments that directly affect the security of others, including the 1987
Intermediate-Range Nuclear Forces (INF) Treaty, the 2002 Open Skies Treaty, and the1991 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.
6
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 militaryconfrontation 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, andcommunications (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 strikecapabilities 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 andChinese strategy, Russia may also rely on threats of limited nuclear first use, or actual firstuse, 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 ourunderstanding of our respective nuclear policies, doctrine, and capabilities; to improvetransparency; 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, andother states’ strategic policies, programs, and capabilities, particularly nuclear, and theflexible, adaptable, and resilient U.S. nuclear capabilities required to protect the UnitedStates, 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
7
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

NUCLEAR DELIVERY SYSTEMS SINCE 2010
Ground-Launched
Sea-Launched
SS-X-28
ICBM

SS-27 Mod 2
ICBM

SSC-08GLCM

CHINA

SS-19 Mod-X-4
ICBM

CSS-10 Mod
1/2 ICBM

CSS-4 Mod
2/3 ICBM

Hwasong-12
IRBM

Hwasong-14
ICBM

SS-N-30SLCM

Musudan
IRBM

Hwasong-13
ICBM

Kh-32
ALCM

PAK-DA
Bomber

PAK-FA
DCA

JL-2
SLBM

Type 094
SSBN

Type 096
SSBN

JL-3
SLBM

Pukguksong-2
MRBM
Gorae
SSB

Nodong
MRBM

Status-6
AUV

Pukguksong-1
SLBM

Hwasong-15
ICBM

UNITED STATESNORTH KOREAER SCUDMRBM

CSS-5 Mod
6 MRBM

Kh-102
ALCM

Yasen
SSGN

Borei
SSBN

SS-N-32SLBM

CSS-X-20
ICBM

DF-26
IRBM

SCUD CSRBM

SS-X-29ICBM

Air-Launched

F-35A

KEY

Figure 1. Nuclear Delivery Systems Since 2010
Data provided by the DoD

DEVELOPMENT

FIELDED

LAND

RussiaRussia considers the United States and the North Atlantic Treaty Organization (NATO) tobe the principal threats to its contemporary geopolitical ambitions. Russian strategy anddoctrine 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. Thesemistaken perceptions increase the prospect for dangerous miscalculation and escalation.
8
NUCLEAR POSTURE REVIEW

SEA

AIR

Russia has sought to enable the implementation of its strategy and doctrine through acomprehensive 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 anddeploying new nuclear warheads and launchers. These efforts include multiple upgradesfor 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.

“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 andcapabilities for expanding the role of nuclear weapons in its security strategy.”
U.S. National Intelligence Council, 2012
Russia possesses significant advantages in its nuclear weapons production capacity and innon-strategic nuclear forces over the U.S. and allies. It is also building a large, diverse, andmodern set of non-strategic systems that are dual-capable (may be armed with nuclear orconventional 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 flighttesting 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
President Vladimir Putin and Defense Minister General
missile defense system and designing a RussianSergey Shoigu in the National Defense Council Center. (Photo bynewballistic
missiledefense Russian Ministry of Defense)
interceptor.
9
NUCLEAR POSTURE REVIEWRESPONDING TO RUSSIA’S INF TREATY VIOLATION
In July 2014, the United States declared Russia to be in violation of the INF Treaty forthe 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; NATOurges Russia to address these concerns in a substantial and transparent way.” – December
15th, 2017RESPONSE 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 researchand development by reviewing military concepts and options for conventional, groundlaunched, intermediate-range missile systems.

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 ofnuclear weapons.

10
NUCLEAR POSTURE REVIEWChinaConsistent with Chinese President
Xi’s statement at the 19th Party
Congress that China’s military willbe “fully transformed into a first tierforce” by 2050, China continues toincrease the number, capabilities,
and protection of its nuclear forces.
While China’s declaratory policy anddoctrine have not changed, its lack oftransparency regarding the scope andscale of its nuclear modernization
program raises questions regarding
its future intent.
China has China's CSS-X-20 ICBM on parade in 2015. (Photo by Xinhua News)
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 newsubmarine-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 anuclear-capable precision guided DF-26 intermediate-range ballistic missile capable ofattacking 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 istesting 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 byfurther 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 Statesand 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 theUnited 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
11
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; existingchemical, biological, and conventional capabilities; and extremely provocative rhetoric andactions, 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 nuclear weapons and missile programs will continue to pose aserious threat to US interests and to the security environment in East Asia in
2017. North Korea’s export of ballistic missiles and associated materials toseveral 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
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
Kim Jong-un inspecting the Hwasong-14 ICBM. (Photo by the Korean
threatens with nuclear attack.
Central News Agency)

12
NUCLEAR POSTURE REVIEWIran

Iran, too, poses proliferation threats. Iran’s Supreme Leader, Ayatollah Ali Khamenei, hasmost 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 technologicalcapability and much of the capacity necessary to develop a nuclear weapon within one yearof a decision to do so. Iran’s development of increasingly long-range ballistic missile
capabilities, and its aggressive strategy
andactivities
todestabilize
neighboring governments, raises
questions about its long-term
commitment to foregoing nuclear
weapons capability. Were Iran topursue nuclear weapons after JCPOA
restrictions end, pressures on othercountries in the region to acquire
their own nuclear weapons would
increase.
Nuclear terrorism remains a threat to
the United States and to international Iranian test launch of a modified Fateh-110. (Photo by the Iranian
Ministry of Defense)
security and stability. Preventing theillicit acquisition of a nuclear weapon, nuclear materials, or related technology andexpertise 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 ofterrorist acquisition. Further, given the nature of terrorist ideologies, we must assume thatthey 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 the2010 NPR demonstrates that unanticipated developments and uncertainty about near- andlong-term threats to the United States, allies, and partners are factors we must consider informulating 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 thepolicy, strategy, and programmatic foundation for sustaining and replacing the entire U.S.

13
NUCLEAR POSTURE REVIEW

nuclear force needed to address threats decades into the future, it focuses on theimplications 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 geopoliticaluncertainty. This includes the potential for rapid shifts in how other states view the UnitedStates, 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 forunanticipated technological breakthroughs in the application of existing technologies, orthe 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 thatwould 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, andposture. 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 willarise. 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. Ensuringthat U.S. nuclear capabilities have the flexibility and attributes necessary to respond to thepossible shocks of a changing threat environment is our responsibility to future generations.

14
NUCLEAR POSTURE REVIEWIII. Why U.S. Nuclear Capabilities?
“Our nuclear deterrent underwrites all courses of diplomacy
and every military operation…there is a direct line between asafe, secure, and reliable nuclear deterrent…and our
responsibility as global defenders of freedom.”
U.S. Air Force Chief of Staff, General David Goldfein, 201715
NUCLEAR POSTURE REVIEWIII. Why u.S. nuclear capabilities

U.S. Nuclear Capabilities

The fundamental reasons why U.S. nuclear capabilities and deterrence strategies arenecessary 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 toensure 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 makepossible 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 withvisiting 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.

16
NUCLEAR POSTURE REVIEWever higher casualties and damage to society. During the first half of the 20th century andjust 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 madeessential 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.

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

CONVENTIONAL ERA

2.5%% OF TOTAL POPULATION

2.27%

2%

WWII

1.75%

WWI

1.5%

1.31%

1.15%

1%

1.12%

0.5%

0.4%
<0.01%
1600

1650

1700

1750

1800

1850

1900

1950

2000

Figure 2. Wartime Fatalities Percentage of World Population
Data from the DoD Historical OfficeNon-nuclear forces also play essential deterrence roles. Alone, however, they do notprovide comparable deterrence effects, as reflected by the periodic and catastrophic failuresof conventional deterrence to prevent Great Power wars throughout history. Similarly,
conventional forces alone do not adequately assure many allies and partners. Rather, thesestates place enormous value on U.S. extended nuclear deterrence, which correspondingly
is also key to non-proliferation.
17
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 bevulnerable to coercion and attack by adversaries who retain or expand nuclear arms andincreasingly lethal non-nuclear capabilities. Until the “fundamental transformation of theworld political order” takes place, U.S. nuclear weapons remain necessary to prevent war
and safeguard the Nation.

18
NUCLEAR POSTURE REVIEWIV. Enduring National Objectives
and the Roles of Nuclear Weaponsin U.S. National Security Strategy“We believe that by improving deterrence across the broad
spectrum, we will reduce to an even lower point the probabilityof a nuclear clash between ourselves and other major powers.”
Secretary of Defense James Schlesinger, 1974

19
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 andfuture 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 arealso 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, andrequirements.
Deterrence of Nuclear and Non-Nuclear Attack

The highest U.S. nuclear policy andstrategy priority is to deter potential
adversaries from nuclear attack ofany 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 ofdeterrence strategies changes acrosstime and circumstance, but thefundamental nature of deterrence An unarmed Trident II D5 missile launches from the Ohio-classendures: it is about decisively fleet ballistic-missile submarine USS Maryland (SSBN 738) off theof Florida. The test launch was part of the U.S. Navy Strategic
influencing an adversary’s decision coast
Systems Programs demonstration and shakedown operation
calculus to prevent attack or the certification process. The successful launch certified the readinessescalation of a conflict. Potential of an SSBN crew and the operational performance of thesubmarine's strategic weapons system before returning toadversaries must understand that operational availability (U.S. Navy Photo)
aggression against the United States,
allies, and partners will fail and result in intolerable costs for them. We deter attacks byensuring the expected lack of success and prospective costs far outweigh any achievablegains.
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NUCLEAR POSTURE REVIEW

U.S. deterrence strategy has always integrated multiple instruments of national power todeter nuclear and non-nuclear attack. Integrating and exercising all instruments of powerhas become increasingly important as potential adversaries integrate their militarycapabilities, 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 ofcapabilities needed to ensure that nuclear or non-nuclear aggression against the UnitedStates, allies, and partners will fail to achieve its objectives and carry with it the crediblerisk of intolerable consequences for the adversary. U.S. forces will ensure their ability tointegrate nuclear and non-nuclear military planning and operations. CombatantCommands and Service components will be organized and resourced for this mission, andwill 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 warningand 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 rightto make any adjustment in the assurance that may be warranted by the evolution and proliferationof non-nuclear strategic attack technologies and U.S. capabilities to counter that threat.
21
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, sucha policy is not justified today. It remains the policy of the United States to retain someambiguity 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 topotential 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 theUnited 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 andthe Russian Federation] are in fact highly stable. They are subject to multiple layers ofcontrol, ensuring clear civilian and indeed Presidential decision-making.” Over more thanhalf 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 commitmentsthat assure European, Asian, andPacific allies. The United States will
ensurethecredibility
andeffectiveness of those commitments.
Assurance is a common goal andadvances 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 tounderstand each other’s threat U.S. Air Force F-35A Lightning IIs and Japanese Air Self Defense
F-15 Eagles fly in formation during bi-lateral training December
perceptions and to arrive at a shared Force
4, 2017, over the Pacific Ocean. (U.S. Air Force photo)
understanding of how best to
22
NUCLEAR POSTURE REVIEWdemonstrate our collective capabilities and resolve. No country should doubt the strengthof our extended deterrence commitments or the strength of U.S. and allied capabilities todeter, 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 thecredibility 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 FailFor deterrence to be credible, theUnited 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
cancomplement but not replace U.S.
nuclear capabilities for this purpose.
All U.S. Presidents since 1945 haveconsidered U.S. employment ofradar navigator assigned to the 2nd Bomb Wing, Barksdale Air Forcenuclear weapons only in extreme ABase,
La., watches monitors on a B-52 Stratofortress during a mission
circumstances and for defensive in support of bomber assurance and deterrence operations at Royal Air
purposes. If deterrence fails, the Force Fairford, England, September 19, 2017. (Air Force photo)
initiation and conduct of nuclear operations would adhere to the law of armed conflict andthe Uniform Code of Military Justice. The United States will strive to end any conflict andrestore deterrence at the lowest level of damage possible for the United States, allies, andpartners, 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 ina regional contingency calls for robust adaptive planning to defeat and defend against
attacks, including missile defense and capabilities to locate, track, and target mobile systemsof 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 thecase 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.
23
NUCLEAR POSTURE REVIEWHedge against an Uncertain Future

The United States will continue
efforts to create a more cooperativeand benign security environment,
but must also hedge againstprospective and unanticipated risks.
Nuclear capabilities alone do notprovide the basis for hedging against
future uncertainty; non-nuclear
forces also play a critical role.
However, U.S. nuclear capabilities
provide a necessary, unique, andcurrently irreplaceable contribution.

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 transporterin the F.E. Warren Air Force Base, Wyo., missile complex, August24, 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)

Hedging strategies help reduce risk
and avoid threats that otherwise may
emerge over time. Given theincreasing prominence of nuclear
weapons in the defense policies andstrategies 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 thedevelopment, 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 andeffective solutions.

24
NUCLEAR POSTURE REVIEW

V. Tailored Strategies
and Flexible Capabilities“The challenges that each situation may present, such as time, placeand circumstance, are distinct. Therefore, flexibility and adaptivenessare essential in a defence planning process that can never be informed
reliably about the future contexts for action and requirements.”
Professor Colin S. Gray, 201725
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 topotential 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.

26
NUCLEAR POSTURE REVIEW

of nuclear weapons in U.S. national security strategy. Flexibility must address a spectrumof 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 policyof “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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NUCLEAR POSTURE REVIEW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 makecertain those weapons are never used.”
Secretary of Defense James Mattis, August 201729
NUCLEAR POSTURE REVIEW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 NATOas 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 andother important commitments.
Most concerning are Russia’snational security policies, strategy,
and doctrine that include anemphasis on the threat of limited
nuclear escalation, and its
continuing development and Russian SS-27 Mod 2 ICBM on parade in Moscow. (Photo by the
Russian Ministry of Defense)
fielding of increasingly diverse andexpanding 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 theconsequences of limited nuclear first use, either regionally or against the United Statesitself. Russia must instead understand that nuclear first-use, however limited, will fail toachieve 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 useof 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 andensure the credible prospect of unacceptably dire costs to the Russian leadership if it wereto choose aggression.

30
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 andstrategic 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. NATOwill 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—thePresident 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. andother 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 andpursuit of regional dominance haveemerged as a major challenge to U.S.
interests in Asia. It has adopted anincreasingly assertive posture indisputes with its neighbors, many ofwhom are U.S. allies or partners.
These encompass a variety ofhistorical and border disputes,
includingoverterritorialboundaries, claims to contested
island territory, and an islandbuilding campaign in the South A JIN-class Type 094 ballistic missile submarine. (Photo by the
China Sea. China possesses nuclear People’s Liberation Army-Navy)
warheads on protected ICBMs and SLBMs capable of reaching the United States andnuclear-armed, theater-range ballistic missiles capable of reaching U.S. territory, allies,
partners, forces, and bases in the region. China’s expanding non-nuclear militarycapabilities include space and cyber warfare capabilities that could decisively affect theoutcome of a conflict.
31
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 toprevent Beijing from mistakenly concluding that it could secure an advantage through thelimited 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 ofChinese 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 apeaceful 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 toashes 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 territoryand naval vessels, and test launching missiles over Japan.

32
NUCLEAR POSTURE REVIEWFor North Korea, the survival of theKim regime is paramount. Our
deterrence strategy for North Korea
makes clear that any North Korean
nuclear attack against the UnitedStates or its allies and partners is
unacceptable and will result in theend of that regime. There is no
scenario in which the Kim regime
could employ nuclear weapons andsurvive. Further, we will hold theKim regime fully responsible for any
transfer of nuclear weapons Kim Jong-un observing a recent missile launch. (Photo by the Korean
technology, material or expertise to Central News Agency)
any state or non-state actor.
North Korea relies on hardened and deeply buried facilities to secure the Kim regime andits key military and command and control capabilities. It uses underground facilities andnatural terrain features to protect North Korean military forces. Consequently, the UnitedStates will continue to field a range of conventional and nuclear capabilities able to holdsuch targets at risk.
In addition to ensuring the ability to impose intolerable costs on the Kim regime, the UnitedStates 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 forthese 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 overneighboring 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 anattempt to create exploitable military advantages.

33
NUCLEAR POSTURE REVIEWIran continues to invest in the largest
missile program in the Middle Eastand could, in the future, threaten ordeliver nuclear weapons were Iran toacquire 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 U.S. Ambassador to the United Nations Nikki Haley discusses evidenceof Iran’s destabilizing activities in the Middle East and Iran’s effort tochemical and biological weapons.
cover up continued violations of U.N. resolutions during a news
conference at Joint Base Anacostia-Bolling in Washington, D.C.,

Many of the JCPOA’s key December 14, 2017. (DoD photo)
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, andpartners 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 thatany 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 ofprecluding or degrading Tehran’s missile threats. The United States will continue tostrengthen 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 Statesaffirms 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 andits 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.
34
NUCLEAR POSTURE REVIEWOur ability to continue assuring allies and partners is challenged by the range and diversityof potential adversaries and the threats they pose. The United States extends deterrence toover 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 ofa 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 ofpotential 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, andpolitical 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: sharedinterests 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 effectivemeans of deterring aggression andpromoting peace and stability in theEuro-Atlantic region.
NATOfollowed the U.S. post-Cold War
trend in deemphasizing the role ofnuclear weapons in NATO’s
deterrence and defense posture, but
the Alliance never lost sight of the
Sukhoi Su-24 attack aircraft makes a very low altitude passfundamental purpose NATO’s nuclear AbyRussian
USS Donald Cook (DDG 75) April 12, 2016. Donald Cook, ancapabilities play in preserving peace, Arleigh Burke-class guided-missile destroyer forward deployed toSpain, is conducting a routine patrol in the U.S. 6th Fleet area
preventing coercion, and deterring Rota,of operations in support of U.S. national security interests in Europe.
aggression.
(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, andintroduced 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 aconflict, but would result in unacceptable costs to an adversary that would far outweigh thebenefit it could hope to achieve. The Alliance has already initiated measures to ensure thatNATO’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 caneffectively integrate nuclear and non-nuclear operations, if deterrence fails; and›Ensure the NATO NC3 system is modernized to enable appropriate consultations andeffective nuclear operations, improve its survivability, resilience, and flexibility in themost 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 anessential 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 mosteffective means of assurance in the Asia-Pacific region. However, North Korea, China, andRussia each present unique, and in some ways more complex, threats to our allies and36
NUCLEAR POSTURE REVIEWinterests in the Asia-Pacific region.
Further, the perception and immediacyof 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, inAsia we have a series of bilateralarrangements with varying degrees ofmultilateral cooperation across different
missions. Our nuclear posture, too, is The U.S.-Japan Bilateral Commission on Civil Nuclear
different. Following the Cold War, the Cooperation tour an Aerial Measuring System helicopter.
United States removed all of its nuclear (Photo provided by NNSA)
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 theassurance 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 andcorresponding 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 becharacterized with certainty today. The combination of a highly dynamic security
environment and the rapid advancement and spread of military technology creates a rangeof possible threat developments for which we must be prepared. Additionally, the UnitedStates is embarking on a nuclear force sustainment and replacement program which is justin time. This requires a high degree of concurrency and synchronization and, thus, has thepotential for scheduling shortfalls. We cannot predict with confidence when or if any ofthese potential challenges will occur, but there always exists the potential for geopolitical
37
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-scaleconventional 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, thatcreate a new threat to U.S. nuclear deterrent capabilities.

›

Operational risk includes the potential for operational shortfalls that reduce theeffectiveness of U.S. nuclear forces. It includes reduced availability of deployed forces,
intelligence collection gaps that inhibit identification or characterization of designatedtargets, 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 programsfor 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 ofgeopolitical, technological, operational, and programmatic risk; and, reducing the harmthat 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 through38
NUCLEAR POSTURE REVIEW

diplomacy; and 3) dissuading adversaries from attempting to challenge U.S., allied, andpartner 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 willcontinue 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 thecurrent and potential future security environments. This will include threat-based analysesof what potential adversaries are doing or considering today, as well as what is possible inlight of projected advancement and diffusion of technology. Finally, the United States willremain at the forefront of science and technology to reduce the likelihood of technologicalsurprise.
Risk reduction through diplomacy. We will seek opportunities for diplomatic agreementsthat reduce the likelihood of future security challenges via mutual restraints that reduce thepotential 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 geopoliticalchallenges 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 tomeet any such challenge. Therefore, in preparing to respond to geopolitical challenges, wewill 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 addresschanges 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 geopoliticalthreat 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 bysustaining 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
39
NUCLEAR POSTURE REVIEWupload hedge weapons onto existing delivery platforms to augment the deployed force asnecessary 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 atechnologicalor
geopoliticalchallenge that threatens an element of
U.S. nuclear forces. These attributes
include survivability, the ability topenetrate adversary defenses, theability to visibly signal deterrence
messages, prompt response, and arange of warhead yield options.
This strategy for risk mitigation helps Researcher prepares a global burst detector subsystem for a test in
to hedge against the possibility that an the flight test chamber at Sandia National Laboratories in
Albuquerque, N.M., August 4, 2016. (Photo by Randy Montoya)
operational or technical problem oradversary breakthrough would compromise the effectiveness of our nuclear forces. It also
helps to preclude nuclear arms competition by communicating to adversaries that we candeny 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 futurerisk exposure by ensuring that flexibility is built into and sustained in our current and futurenuclear force structure. This applies to delivery systems, platforms, warheads, commandand 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, theUnited 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.

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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 andinfrastructure—in many cases for decades beyond what was originallyintended. 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, 201741
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 ofmembers of the United States Armed
Forces and civilian personnel who
dedicate their professional lives to thedeterrence of war and protecting the
Nation. These exceptional men andwomen 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 Airman 1st Class stands guard at Minot Air Force Base, N.D.,
Carter stated in 2016 when speaking to October 31, 2017, during Global Thunder 18. (U.S. Air Force
Air Force Service members at Minot Air photo)
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 withlittle 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 todeter effectively and respond as necessary to different threats and circumstances. Thisrequirement is now magnified by the need to tailor U.S. strategies to a broader range ofadversaries 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 and42
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 isnecessary. The multiplicity of platforms, weapons, and modes of operation inherent in thetriad and U.S. non-strategic nuclear forces, provide a significant margin of flexibility andresilience. 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 designphases that enable us to modify systems in the future at lower cost and with greater speed.
The triad must be considered as awhole because it functions as awhole, with each leg essential tooverall effectiveness. As Secretary of
Defense Mattis concluded regarding
deterrence requirements and thetriad, “I also have looked at – I havequestioned the triad, and I cannot
solve the deterrent problem
reducing it from a triad. If I want tosend the most compelling message, I
have been persuaded that the triad inits framework is – is the right way to Marine Corps General Joe Dunford, chairman of the Joint Chiefs ofmeets with the crew of a B-52H at Minot Air Force Base, N.D.,go.”
The triad’s synergy and Staff,
November 2, 2016. (DoD photo)
overlapping attributes help ensure
the enduring survivability of our deterrence capabilities against attack and our capacity tohold a range of adversary targets at risk throughout a crisis or conflict. Eliminating any legof the triad would greatly ease adversary attack planning and allow an adversary toconcentrate 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.

43
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 topose 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 geographicallocations 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 adisarming 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 ForceThe 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 mostsurvivable leg of the triad. When on patrol, SSBNs are, at present, virtually undetectable,
44
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 otherneededattributes.
Theirintercontinental range and constantreadiness allows them to hold targets
at risk throughout Eurasia from theirlaunch areas in the Atlantic and Pacificoceans. 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 The OHIO-class ballistic-missile submarine USS Kentucky (SSBN 737)
can upload additional warheads if transits the Hood Canal as the boat returns to Naval Base KitsapBangor following the boat's first strategic deterrent patrol since 2011.
necessary, contributing to the U.S. (U.S. Navy photo)
hedge capacity.
Finally, SSBNs are highly mobile. They can demonstrate U.S. nuclear presence andcommitment 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 throughthe 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 ForceThe 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 legof 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 acrisis.

45
NUCLEAR POSTURE REVIEWThe ICBM force is highly survivableagainst any but a large-scale nuclear
attack. To destroy U.S. ICBMs on the
ground, an adversary would need tolaunch a precisely coordinated attack
with hundreds of high-yield andaccurate warheads.
This is an
insurmountable challenge for any
potential adversary today, with the
exception of Russia. In contrast, in theabsence of our ICBM force, a large
proportion of our strategic nuclear
triad, including SSBNs in port and non- An unarmed Minuteman III intercontinental ballistic missile during
alert bombers, could be subject to an an operational test at 2:10 a.m. Pacific Daylight Time Wednesday,
2, 2017, at Vandenberg Air Force Base, Calif. (U.S. Air Forceattempted nuclear first strike involving Aug.
photo)
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 tohold 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 needto 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 strategicballistic 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
46
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 anddispersed, 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 themvirtually unlimited range and endurance. In recent years, B-52 and B-2A bombers havecarried 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 theflexibility valuable for deterrence indifferent circumstances. The gravity
bombs carried by B-2A bombers andthe ALCMs carried by B-52H
bombers provide multiple yield
options. In addition, the B83-1 andB61-11 can hold at risk a variety ofprotected targets. As a result, bothwill be retained in the stockpile, atleast until there is sufficient Air Force Captain flies a B-52H Stratofortress during a training mission
confidence in the B61-12 gravity over North Dakota, January 31, 2017. (Air Force photo)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 canpenetrate advanced air defenses. Beginning in 1982, our B-52H bombers were equippedwith 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 toensure the ALCM can be maintained until its replacement, the Long-Range Stand-Off(LRSO) cruise missile, becomes available.
47
NUCLEAR POSTURE REVIEW

Non-Strategic Nuclear Weapons
During the Cold War, the United States possessedlarge 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, andbe available for these DCA beginning in 2021.
U.S. and NATO DCA, together with U.S. gravity
bombs, are forward deployed in European NATOcountries. Their forward presence contributes
significantly to the deterrence of potential Sandia National Laboratory mechanical engineer
a microphone for an acoustic text on aadversaries and the assurance of allies. Their adjusts
B-61-12 system.
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 movethese 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 fundtheir respective nuclear delivery system and warhead programs to remain on schedule for48
NUCLEAR POSTURE REVIEW

synchronized delivery, and they will seek opportunities to accelerate programs where costeffective.
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 ForceThe 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 anumber 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 replaceelements 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 andgeopolitical 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 successof 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 theUnited 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 withthe 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 beequipped 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 thetriad, 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 andchallenge 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
for an adversary to threaten much of the U.S. deterrent forces in a first-strike attack. Delaysin the B-21 bomber program or associated bomber weapons would reduce the ability of ourstrategic 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 forwhich strategic bombers are particularly well suited.
Flexible and Secure Nuclear Capabilities:
An Affordable Priority“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
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 thenecessity 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, eventhe 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 thereplacement 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 lessthan 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 thelast such investment period in the 1980s, which at the time was almost 3.7 percent of thefederal budget, and the 17.1 percent of the DoD budget required in the early 1960s.

51
NUCLEAR POSTURE REVIEWDOD NUCLEAR ENTERPRISE FUNDING

18%

1962:

16%

TOTAL TRIAD: 17.1%
of DoD Budget

14%

1984:

2029:

TOTAL TRIAD: 10.6%
of DoD Budget

12%

Legacy Triadand
Sustainment
Peak Recapitalization of Nuclear Enterprise
Funding, including 100% of B-21 funding

TOTAL TRIAD: 6.4%
of DoD Budget

Peak Recapitalization:8%

3.7% of DoD Budget

6%

Recapitalization

4%

Legacy Triadand Sustainment

2%

Sustainment:

2.7% of DoD Budget

Figure 3. Cost of DoD Nuclear Force Replacement
Data provided by DoD

2040

2037

2034

2031

2028

2025

2022

2019

2016

2013

2010

2007

2004

2001

1998

1995

1992

1989

1986

1983

1980

1977

1974

1971

1968

1965

0%
1962

PERCENT OF DOD BUDGET

10%

FISCAL YEAR

The projected DoD costs of sustaining and replacing the nuclear capabilities needed tosupport 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 theAmerican 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 theversatility and flexibility of the U.S. triad that only modest supplements are now requiredin this much more challenging threat environment.

52
NUCLEAR POSTURE REVIEWRUSSIA’S NON-STRATEGIC NUCLEAR CHALLENGE

Anti-Ship Missile

Torpedo

GLCM

Depth Charges

Gravity
WeaponAir-to-Surface Missile

Anti-Submarine Missile

CRBM

Anti-Aircraft Missile

SRBM

Anti-Ballistic Missile

RUSSIA

UNITED
STATES

Gravity
Weapon

KEY

LAND

SEA

AIR

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 employableby 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.

These supplements will enhance deterrence by denying potential adversaries any mistaken
confidence that limited nuclear employment can provide a useful advantage over the UnitedStates 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 perceptionthat 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 thisevolving nuclear weapons doctrine appear to lower the threshold for Moscow’s first-use of
53
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 incrises 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, theUnited States will maintain aspectrum of capabilities sized andpostured to meet U.S. needs, andparticularly to ensure that noadversary under any circumstances
can perceive an advantage throughlimited nuclear escalation or otherstrategic attack.
For decades, the United States has
deployed low-yield nuclear options
to strengthen deterrence andassurance. Expanding flexible U.S. U.S. Air Force F-35A Lightning IIs assigned to Hill Air Force Base,taxi at Kunsan Air Base, Republic of Korea, November 27, 2017.
nuclear options now, to include low- Utah
(U.S. Air Force photo)
yield options, is important for thepreservation of credible deterrence against regional aggression. To be clear, this is notintended 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 inlimited nuclear escalation, making nuclear weapons employment less likely.
Consequently, the United States will maintain, and enhance as necessary, the capability toforward 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
54
NUCLEAR POSTURE REVIEW

effect. They will provide additional diversity in platforms, range, and survivability, and avaluable 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. Doingso 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 anuclear-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 mayreconsider 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 andcruise 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 tostrengthen deterrence and assurance, we will immediately begin efforts to restore thiscapability 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 forit 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 diversityof U.S. nuclear capabilities to help address emerging deterrence requirements in the nearterm 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 exploitableadvantage.
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NUCLEAR POSTURE REVIEW

Nuclear Command, Control, and Communications (NC3)Modernization"We have to modernize the entire architecture. And so, as you see themodernization 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 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; andenabling the management and directionof forces.
Today’s NC3 system is a legacy of theCold War, last comprehensively
updated almost three decades ago. It The Advanced Extremely High Frequency, or AEHF, systemprovides survivable, global, secure, protected and jam-resistant
includes interconnected elements communications for high-priority military ground, sea and air
composed of warning satellites and assets. (U.S. Air Force photo)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
56
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 forgovernance 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 increasinglycongested, competitive, and contested. A number of countries, particularly China andRussia, 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 andpotential vulnerabilities for the NC3 system. Potential adversaries are expending
considerable effort to design and use cyber weapons against networked systems. While ourNC3 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 oflimited nuclear options, our NC3 system must be resilient in the context of adversary
limited nuclear strikes. The U.S. leadership, including Combatant Commanders, must beable to communicate and share information across networked command and control
systems, and to integrate nuclear and non-nuclear military planning and operations in thecontext of adversary nuclear employment.

Modernizing the NC3 System
In light of the critical need to ensure our NC3 system remains survivable and effective incrisis 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 spaceassets are agile and resilient, thereby deterring and if necessary overcoming attempts toextend conflict into space. The United States will enhance the training of operational spaceforces to ensure that we are prepared to successfully achieve mission objectives against therange of 21st century threats.
57
NUCLEAR POSTURE REVIEWStrengthen Protection Against Cyber Threats. The United States will protect NC3components against current and future cyber threats and ensure the continuing availabilityof U.S.-produced information technology necessary for the NC3 system.
Enhance Integrated Tactical Warning and Attack Assessment. The United States willdevelop a future architecture which will include modernized SBIRS satellites and integratemissile defense sensors to maximize warning time. The United States will also continue totransition the DSP system to SBIRS and enhance ground-based radars. The upgraded SBIRS
constellation will include six satellites supported by the existing DSP architecture toenhance the survivability of U.S. satellites. Additionally, we will continue to sustain andupgrade the USNDS to support accurate attack assessment.
Improve Command Posts and Communications Links. The United States will upgrade andmodernize 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 toenhance command and control, andfield modernized communicationtransmitters and terminals across theNC3 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 toadapt new technologies for information
display and data analysis to improve
support for Presidential decision
making and senior leadership Missile Technician 3rd Class, Senior Chief Missile Technician andMachinist's Mate, all assigned to the Ohio-class ballistic-missile
consultations.
submarine USS Alaska (SSBN 732), operate the controls of thedive simulator at the Trident Training Facility. (U.S. Navy photo)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 ofadversary 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, andexercise 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 toaddress 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 Secretaryof Defense no later than May 1, 2018, a plan to reform NC3 governance to ensure its
effective functioning and modernization.
58
NUCLEAR POSTURE REVIEWVIII. Nuclear Weapons
Infrastructure“NNSA’s ability to achieve its vital national security missions isdependent 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 theenvironment at risk.”
NNSA Administrator, Frank Klotz, 201759
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, anddiscourage 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, andeffectiveness;›

Extend the life of a select sub-set of nuclear warheads, and design, develop, andproduce 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 asafeguard, maintain a nuclear test capability;›

Maintain the capability to design, develop and produce nuclear warheads with new ordifferent 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,
nuclearcounterterrorism, and emergency
response.
The main challenge to an effective
and resilient infrastructure is theneedtomaintaindesign,development, manufacturing, andtesting capabilities during thelengthy periods of time between
rebuilding cycles to ensure theenduring health of the infrastructure.
During the Cold War, the United Machinists at Lawrence Livermore National Laboratory use a state-ofthe-art hydraulic press needed for W80-4 work. (Photo provided by
States carried out an intensive and NNSA)
60
NUCLEAR POSTURE REVIEWbalanced program on roughly a five-year cycle. The last new, modern warheaddevelopment 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 anddeliver 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 andcompleting 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 suitablereplacement is identified; and,›

Exploring future ballistic missile warhead requirements based on the threats andvulnerabilities of potential adversaries, including the possibility of common reentry
systems between Air Force and Navy systems.

Over the past several decades, theU.S. nuclear weapons infrastructure
has suffered the effects of aging andunderfunding. 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 tomaintain 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 Detector for Advanced Neutron Capture Experiments at Los Alamos
developments. There is now no Neutron Science Center. (Photo provided by NNSA)
61
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 throughrefurbishment, at present the United States does not have the ability to produce new
nuclear weapons.” While North Korea can illicitly produce nuclear warheads, the UnitedStates 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, ournuclear 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 toit.
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 theUnited States must have sufficientresearch, design, development, andproduction capacity to support thesustainment and replacement of its
nuclear forces. To meet these needs,
the United States must resolve thecurrent significant infrastructure Secretary Perry meets with Yukiya Amano, Director General of IAEA
March 20, 2017 at the Department of Energy. (Photo provided byfunding shortfalls over the next five on
DOE)
years.
62
NUCLEAR POSTURE REVIEWTo remain postured to address challenges that may emerge, the United States needs theflexibility to hedge against future risks. Consequently, NNSA will explore approaches for
rapid prototyping, develop options for modifying warheads to increase flexibility andresponsiveness, examine the potential for retired warheads and components to augment
the future hedge stockpile, and survey past and extant warhead designs to better understandwhat can be certified without resuming full-scale nuclear testing. An additional measurefor 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 will continue to observe a nuclear test moratorium that began in 1992.
This posture was adopted with the understanding that the United States must remain readyto resume nuclear testing if necessary to meet severe technological or geopoliticalchallenges.
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 atechnical or geopolitical development demand a new nuclear weapon, it is crucial that thenuclear 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 newwarhead designs from initial concept through development, prototyping, and plans forcertification, NNSA should assess capabilities currently being exercised by: life extension
programs, stockpile certification, laboratory directed research and development, andtechnology maturation. On this basis, NNSA will identify any gaps in the full range of theskills needed to design and develop nuclear weapons. The Stockpile Responsiveness
Program that Congress recently instituted with bipartisan support explicitly directs that theUnited 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 meetchanges in the security environment.
The United States will pursue initiatives to ensure the necessary capability, capacity, andresponsiveness of the nuclear weapons infrastructure and the needed skills of the nuclear
enterprise workforce, including the following:

63
NUCLEAR POSTURE REVIEW›

Pursue a joint DoD and DOE advanced-technology development capability to ensurethat efforts are appropriately integrated to meet DoD needs.

›

Provide the enduring capability and capacity to produce plutonium pits at a rate of nofewer than 80 pits per year by 2030. A delay in this would result in the need for ahigher rate of pit production at higher cost.

›

Ensure that current plans to reconstitute the U.S. capability to produce lithiumcompounds 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 tomeet 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 andhedging 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.

64
NUCLEAR POSTURE REVIEWIX. Countering
Nuclear Terrorism“[W]e must prevent nuclear weapons and materials fromcoming into the hands of terrorists and being used against us,
or anywhere in the world...”President Donald Trump, August 21, 2017

65
NUCLEAR POSTURE REVIEWIX. Countering nuclear terrorism

Nuclear terrorism remains among
the most significant threats to thesecurity of the United States, allies,
and partners. The Joint Chiefs ofStaff, in 2015, emphasized,“Nuclear, chemical, and biologicalagents 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 ourhomeland as possible is a key mission U.S. Airmen from the 193rd Special Operations Squadron, prepare toboard an EC-130J Commando Solo aircraft December 2, 2017, at
for the U.S. military.”
193rd Special Operations Wing, Middletown, Pennsylvania. (U.S. Air
National Guard photo)

U.S. strategy to combat the threat ofnuclear 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 theseassets; and respond to nuclear incidents, by locating and disabling a nuclear device ormanaging 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 andattribution capabilities.

›

Strengthening defenses against nuclear terrorism to protect the American people andU.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 thenumber of nuclear facilities and the quantity of nuclear material worldwide continue toincrease, we will maintain our focus on reducing the vulnerability of these materials to theftor seizure. We will also decrease the availability of sensitive equipment and technologies
on the black market and thereby hinder terrorist access to them.

66
NUCLEAR POSTURE REVIEWThe most effective way to reduce
the risk of nuclear terrorism is tosecure nuclear weapons andmaterials at their sources. The
United States will continue towork with allies and partners to
disrupt proliferation networks andinterdict transfers of nuclear
materials and related technology.
In particular, we will improvecoordination with international
export-control
andlawenforcement agencies to bolster
in Prominent Hunt 17-2, an interagency Nuclear Forensics
information sharing to detect and Participants
Exercise, held in New Mexico. (Photo provided by NNSA)
interdict nuclear and radiologicalmaterial. Through collaboration with foreign partners, we will maintain the constellationof radiation detection technologies that have been deployed in 60 countries around theworld 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 tosearch 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 attributethe source of a nuclear attack by
establishing a nuclear materials
archive to store, consolidate, andanalyzehigh-value
nuclearmaterials.
The United States will hold fully
accountable any state, terroristgroup, 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 Soldiers from the Hawaii National Guard's 93rd Weapons of Mass
Civil Support Team receive hands-on training with the Talon
nuclear terrorism is limited, for Destruction
IV unmanned robot at the Robot Logistics Support Center, in Lexington,effective
deterrence
our 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 UnitedStates 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, andpartner 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 ofnuclear-armed states, including by maintaining credible U.S. extended nuclear deterrence
and assurance; 2) deny terrorist organizations access to nuclear weapons, materials, andexpertise; 3) strictly control weapons-usable material, related technology, and expertise;and 4) seek arms control agreements that enhance security, and are verifiable andenforceable.
Non-Proliferation and the Nuclear
Non-Proliferation Treaty

The NPT is the cornerstone of the nuclear non-proliferation regime. It provides the formalinternational legal framework for measures to constrain and deny proliferators and to
identify, contain, and sanction
transgressors.
The Treaty
establishes a framework governingpeaceful uses of nuclear energy,
allowing states to pursue civil
nuclear programs under safeguards
that help provide transparency andconfidence that such programs will
not contribute to proliferation. The
NPT’s positive role in building
consensus for non-proliferation
enhances international efforts toimpose costs on those who would NNSA and the Institute of Nuclear Physics in Kazakhstan collaborate
remove all HEU from the institute’s reactor. (Photo provided bypursue nuclear weapons outside the to
NNSA)
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 byits 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 overthirty 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.
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Nuclear non-proliferation today faces acute challenges. Most significantly, North Korea ispursuing a nuclear path in direct contravention of the NPT and in direct opposition tonumerous 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 thisthreat.
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 foruse 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 theimposition 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 willcontinue to pursue the political andsecurity conditions that could enablefurther nuclear reductions. We will
work to increase transparency andpredictability, where appropriate, toavoid potential miscalculation among
nuclear weapons states and otherpossessor states through strategic
dialogues,risk-reduction
communications
channels,andsharing of best practices related to Arizona Army National Guard Soldiers from the 2220th
Company are engulfed by colored smoke after
nuclear weapons safety and security. Transportation
putting on their protective masks during a simulated chemical attack
August 5, 2017 at Florence Military Reservation in Florence, Ariz.

To further strengthen the NPT The Guardsmen conducted nuclear, biological and chemical warfare
which included entering a gas chamber and being exposed toregime, the United States will support training
CS tear gas. (U.S. Army National Guard photo)
initiatives to improve capabilities todetect, deter, and attribute proliferation and use; reduce the vulnerability of nuclear andradiological 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
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attribution purposes by establishing a nuclear materials archive to store, consolidate, andanalyze 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 thetechnical challenges of verifying nuclear reductions, and therefore will explore newconcepts 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 employmentof improvised nuclear devices; attribute responsibility to perpetrators; and mitigate theconsequences 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 toensure 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 forsignature at the U.N. in 2017, is fueled by wholly unrealistic expectations of the eliminationof 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 posturesin a verifiable and enforceable manner, arms control can help establish a useful degree ofcooperation and confidence among states. It can foster transparency, understanding, andpredictability in adversary relations, thereby reducing the risk of misunderstanding and72
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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 UnitedStates and Soviet Union increasedtransparency,
moderatedcompetition, codified rough parity instrategic nuclear arms, and closed offareas of competition. The most Members of the technical team make adjustments during a reactor
recent 2010 New START Treaty conversion in Ghana. (Photo provided by NNSA)
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 toarms control efforts that advance U.S., allied, and partner security; are verifiable andenforceable; 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 tochange borders and overturn existingnorms, and by significant, continuing
non-compliance with existing arms
control
obligationsandcommitments.
In this regard, Russia continues toviolate a series of arms control
treaties and commitments, the mostsignificant being the INF Treaty. In a
broader context, Russia is either
rejecting or avoiding its obligations
and commitments under numerous (State Department – Open Skies)
agreements, including the Conventional Armed Forces in Europe Treaty, the Budapest
Memorandum, the Helsinki Accords, and the Presidential Nuclear Initiatives. In addition,
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NUCLEAR POSTURE REVIEWRussia has violated the Open Skies Treaty and is selectively implementing the politicallybinding 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 negotiatedreductions, and to pursue reductions in non-strategic nuclear forces.
Regarding the INF Treaty, the United States complies with and remains committed topreserving 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 haspressed 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 inviolation of multiple existing
agreements would indicate a lack ofconsequences for its non-complianceand thereby undermine arms control
broadly.
Consequently, the United States will Air Force Master Sergeant calls range commands during a live-firework to convince states in violation exercise at Fort Carson, Colo., June 9, 2017. He is the first sergeantof their legal arms control assigned to the 233rd Support Group. (Air National Guard photo)
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 areprepared to consider arms control opportunities that return parties to predictability andtransparency, 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 andpartners.

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