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Introduction
The United States has played a leading role in transforming the international system over the
past sixty-five years. Working with like-minded nations, the United States has created asafer, more stable, and more prosperous world for the American people, our allies, and ourpartners around the globe than existed prior to World War II. Over the last decade, we haveundertaken extended operations in Iraq and Afghanistan to bring stability to those countries
and secure our interests. As we responsibly draw down from these two operations, takesteps to protect our nation’s economic vitality, and protect our interests in a world ofaccelerating change, we face an inflection point. This merited an assessment of the U.S.
defense strategy in light of the changing geopolitical environment and our changing fiscal
circumstances. This assessment reflects the President’s strategic direction to the Department
and was deeply informed by the Department’s civilian and military leadership, including the
Joint Chiefs of Staff, the Secretaries of the Military Departments, and the CombatantCommanders. Out of the assessment we developed a defense strategy that transitions our
Defense enterprise from an emphasis on today’s wars to preparing for future challenges,
protects the broad range of U.S. national security interests, advances the Department’s
efforts to rebalance and reform, and supports the national security imperative of deficit
reduction through a lower level of defense spending.
This strategic guidance document describes the projected security environment and the key
military missions for which the Department of Defense (DoD) will prepare. It is intended asa blueprint for the Joint Force in 2020, providing a set of precepts that will help guidedecisions regarding the size and shape of the force over subsequent program and budget
cycles, and highlighting some of the strategic risks that may be associated with the proposed
strategy.

A Challenging Global Security Environment
The global security environment presents an increasingly complex set of challenges andopportunities to which all elements of U.S. national power must be applied.
The demise of Osama bin Laden and the capturing or killing of many other senior al-Qa’ida
leaders have rendered the group far less capable. However, al-Qa’ida and its affiliates
remain active in Pakistan, Afghanistan, Yemen, Somalia, and elsewhere. More broadly,
violent extremists will continue to threaten U.S. interests, allies, partners, and the homeland.
The primary loci of these threats are South Asia and the Middle East. With the diffusion ofdestructive technology, these extremists have the potential to pose catastrophic threats that
could directly affect our security and prosperity. For the foreseeable future, the UnitedStates will continue to take an active approach to countering these threats by monitoring theactivities of non-state threats worldwide, working with allies and partners to establish
control over ungoverned territories, and directly striking the most dangerous groups andindividuals when necessary.

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U.S. economic and security interests are inextricably linked to developments in the arc
extending from the Western Pacific and East Asia into the Indian Ocean region and SouthAsia, creating a mix of evolving challenges and opportunities. Accordingly, while the U.S.
military will continue to contribute to security globally, we will of necessity rebalance
toward the Asia-Pacific region. Our relationships with Asian allies and key partners are
critical to the future stability and growth of the region. We will emphasize our existing
alliances, which provide a vital foundation for Asia-Pacific security. We will also expand
our networks of cooperation with emerging partners throughout the Asia-Pacific to ensurecollective capability and capacity for securing common interests. The United States is also
investing in a long-term strategic partnership with India to support its ability to serve as aregional economic anchor and provider of security in the broader Indian Ocean region.
Furthermore, we will maintain peace on the Korean Peninsula by effectively working withallies and other regional states to deter and defend against provocation from North Korea,
which is actively pursuing a nuclear weapons program.
The maintenance of peace, stability, the free flow of commerce, and of U.S. influence in thisdynamic region will depend in part on an underlying balance of military capability andpresence. Over the long term, China’s emergence as a regional power will have thepotential to affect the U.S. economy and our security in a variety of ways. Our two
countries have a strong stake in peace and stability in East Asia and an interest in building acooperative bilateral relationship. However, the growth of China’s military power must be
accompanied by greater clarity of its strategic intentions in order to avoid causing friction in
the region. The United States will continue to make the necessary investments to ensure that
we maintain regional access and the ability to operate freely in keeping with our treaty
obligations and with international law.  Working closely with our network of allies andpartners, we will continue to promote a rules-based international order that ensures
underlying stability and encourages the peaceful rise of new powers, economic dynamism,
and constructive defense cooperation.
In the Middle East, the Arab Awakening presents both strategic opportunities andchallenges. Regime changes, as well as tensions within and among states under pressure toreform, introduce uncertainty for the future. But they also may result in governments that,over the long term, are more responsive to the legitimate aspirations of their people, and are
more stable and reliable partners of the United States.
Our defense efforts in the Middle East will be aimed at countering violent extremists anddestabilizing threats, as well as upholding our commitment to allies and partner states. Of
particular concern are the proliferation of ballistic missiles and weapons of mass destruction(WMD). U.S. policy will emphasize Gulf security, in collaboration with Gulf Cooperation
Council countries when appropriate, to prevent Iran’s development of a nuclear weapon
capability and counter its destabilizing policies. The United States will do this while
standing up for Israel’s security and a comprehensive Middle East peace. To support theseobjectives, the United States will continue to place a premium on U.S. and allied militarypresence in – and support of – partner nations in and around this region.
Europe is home to some of America’s most stalwart allies and partners, many of whom havesacrificed alongside U.S. forces in Afghanistan, Iraq, and elsewhere. Europe is our principal
partner in seeking global and economic security, and will remain so for the foreseeable

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future. At the same time, security challenges and unresolved conflicts persist in parts ofEurope and Eurasia, where the United States must continue to promote regional security andEuro-Atlantic integration. The United States has enduring interests in supporting peace andprosperity in Europe as well as bolstering the strength and vitality of NATO, which is
critical to the security of Europe and beyond. Most European countries are now producers
of security rather than consumers of it. Combined with the drawdown in Iraq and
Afghanistan, this has created a strategic opportunity to rebalance the U.S. military
investment in Europe, moving from a focus on current conflicts toward a focus on futurecapabilities. In keeping with this evolving strategic landscape, our posture in Europe mustalso evolve. As this occurs, the United States will maintain our Article 5 commitments toallied security and promote enhanced capacity and interoperability for coalition operations.
In this resource-constrained era, we will also work with NATO allies to develop a “Smart
Defense” approach to pool, share, and specialize capabilities as needed to meet 21st century
challenges. In addition, our engagement with Russia remains important, and we willcontinue to build a closer relationship in areas of mutual interest and encourage it to be acontributor across a broad range of issues.
Building partnership capacity elsewhere in the world also remains important for sharing thecosts and responsibilities of global leadership. Across the globe we will seek to be thesecurity partner of choice, pursuing new partnerships with a growing number of nations –
including those in Africa and Latin America – whose interests and viewpoints are merging
into a common vision of freedom, stability, and prosperity. Whenever possible, we willdevelop innovative, low-cost, and small-footprint approaches to achieve our security
objectives, relying on exercises, rotational presence, and advisory capabilities.
To enable economic growth and commerce, America, working in conjunction with allies andpartners around the world, will seek to protect freedom of access throughout the global
commons – those areas beyond national jurisdiction that constitute the vital connective
tissue of the international system. Global security and prosperity are increasingly dependent
on the free flow of goods shipped by air or sea. State and non-state actors pose potential
threats to access in the global commons, whether through opposition to existing norms orother anti-access approaches. Both state and non-state actors possess the capability andintent to conduct cyber espionage and, potentially, cyber attacks on the United States, withpossible severe effects on both our military operations and our homeland. Growth in thenumber of space-faring nations is also leading to an increasingly congested and contested
space environment, threatening safety and security. The United States will continue to lead
global efforts with capable allies and partners to assure access to and use of the global
commons, both by strengthening international norms of responsible behavior and by
maintaining relevant and interoperable military capabilities.
The proliferation of nuclear, biological, and chemical weapons technology has the potential
to magnify the threats posed by regional state actors, giving them more freedom of action tochallenge U.S. interests. Terrorist access to even simple nuclear devices poses the prospectof devastating consequences for the United States. Accordingly, the Department of Defense
will continue to enhance its capabilities, acting with an array of domestic and foreign
partners, to conduct effective operations to counter the proliferation of WMD.

Sustaining U.S. Global Leadership: Priorities for 21st Century Defense3Primary Missions of the U.S. Armed Forces
To protect U.S. national interests and achieve the objectives of the 2010 National Security
Strategy in this environment, the Joint Force will need to recalibrate its capabilities andmake selective additional investments to succeed in the following missions:x Counter Terrorism and Irregular Warfare. Acting in concert with other means ofnational power, U.S. military forces must continue to hold al-Qa’ida and its affiliates andadherents under constant pressure, wherever they may be. Achieving our core goal of
disrupting, dismantling, and defeating al-Qa’ida and preventing Afghanistan from everbeing a safe haven again will be central to this effort. As U.S. forces draw down in
Afghanistan, our global counter terrorism efforts will become more widely distributed
and will be characterized by a mix of direct action and security force assistance.
Reflecting lessons learned of the past decade, we will continue to build and sustain
tailored capabilities appropriate for counter terrorism and irregular warfare. We will also
remain vigilant to threats posed by other designated terrorist organizations, such as
Hezbollah.
x Deter and Defeat Aggression. U.S. forces will be capable of deterring and defeating
aggression by any potential adversary. Credible deterrence results from both thecapabilities to deny an aggressor the prospect of achieving his objectives and from thecomplementary capability to impose unacceptable costs on the aggressor. As a nation
with important interests in multiple regions, our forces must be capable of deterring anddefeating aggression by an opportunistic adversary in one region even when our forces
are committed to a large-scale operation elsewhere. Our planning envisages forces thatare able to fully deny a capable state’s aggressive objectives in one region by conducting
a combined arms campaign across all domains – land, air, maritime, space, andcyberspace. This includes being able to secure territory and populations and facilitate atransition to stable governance on a small scale for a limited period using standing
forces and, if necessary, for an extended period with mobilized forces. Even when U.S.
forces are committed to a large-scale operation in one region, they will be capable ofdenying the objectives of – or imposing unacceptable costs on – an opportunistic
aggressor in a second region. U.S. forces will plan to operate whenever possible withallied and coalition forces. Our ground forces will be responsive and capitalize onbalanced lift, presence, and prepositioning to maintain the agility needed to remain
prepared for the several areas in which such conflicts could occur.
x Project Power Despite Anti-Access/Area Denial Challenges. In order to credibly deter
potential adversaries and to prevent them from achieving their objectives, the UnitedStates must maintain its ability to project power in areas in which our access and freedom
to operate are challenged. In these areas, sophisticated adversaries will use asymmetriccapabilities, to include electronic and cyber warfare, ballistic and cruise missiles,
advanced air defenses, mining, and other methods, to complicate our operational
calculus. States such as China and Iran will continue to pursue asymmetric means tocounter our power projection capabilities, while the proliferation of sophisticatedweapons and technology will extend to non-state actors as well. Accordingly, the U.S.
military will invest as required to ensure its ability to operate effectively in anti-accessSustaining U.S. Global Leadership: Priorities for 21st Century Defense4and area denial (A2/AD) environments. This will include implementing the Joint
Operational Access Concept, sustaining our undersea capabilities, developing a newstealth bomber, improving missile defenses, and continuing efforts to enhance theresiliency and effectiveness of critical space-based capabilities.
x Counter Weapons of Mass Destruction. U.S. forces conduct a range of activities aimed

at preventing the proliferation and use of nuclear, biological, and chemical weapons.
These activities include implementing the Cooperative Threat Reduction (Nunn-Lugar)
Program, and planning and operations to locate, monitor, track, interdict and secure
WMD and WMD-related components and the means and facilities to make them. They
also include an active whole-of-government effort to frustrate the ambitions of nations
bent on developing WMD, to include preventing Iran’s pursuit of a nuclear weapons
capability. In partnership with other elements of the U.S. Government, DoD willcontinue to invest in capabilities to detect, protect against, and respond to WMD use,should preventive measures fail. 
x Operate Effectively in Cyberspace and Space. Modern armed forces cannot conduct
high-tempo, effective operations without reliable information and communication
networks and assured access to cyberspace and space. Today space systems and theirsupporting infrastructure face a range of threats that may degrade, disrupt, or destroy
assets. Accordingly, DoD will continue to work with domestic and international allies
and partners and invest in advanced capabilities to defend its networks, operational
capability, and resiliency in cyberspace and space.
x Maintain a Safe, Secure, and Effective Nuclear Deterrent. As long as nuclear
weapons remain in existence, the United States will maintain a safe, secure, and effective
arsenal. We will field nuclear forces that can under any circumstances confront anadversary with the prospect of unacceptable damage, both to deter potential adversaries
and to assure U.S. allies and other security partners that they can count on America’s
security commitments. It is possible that our deterrence goals can be achieved with asmaller nuclear force, which would reduce the number of nuclear weapons in ourinventory as well as their role in U.S. national security strategy.
x Defend the Homeland and Provide Support to Civil Authorities. U.S. forces willcontinue to defend U.S. territory from direct attack by state and non-state actors. We will
also come to the assistance of domestic civil authorities in the event such defense fails orin case of natural disasters, potentially in response to a very significant or evencatastrophic event. Homeland defense and support to civil authorities require strong,steady–state force readiness, to include a robust missile defense capability. Threats to thehomeland may be highest when U.S. forces are engaged in conflict with an adversary
abroad.
x Provide a Stabilizing Presence. U.S. forces will conduct a sustainable pace of presence
operations abroad, including rotational deployments and bilateral and multilateral training
exercises. These activities reinforce deterrence, help to build the capacity andcompetence of U.S., allied, and partner forces for internal and external defense,strengthen alliance cohesion, and increase U.S. influence. A reduction in resources will

Sustaining U.S. Global Leadership: Priorities for 21st Century Defense5require innovative and creative solutions to maintain our support for allied and partnerinteroperability and building partner capacity. However, with reduced resources,
thoughtful choices will need to be made regarding the location and frequency of these
operations.
x

Conduct Stability and Counterinsurgency Operations. In the aftermath of the wars
in Iraq and Afghanistan, the United States will emphasize non-military means andmilitary-to-military cooperation to address instability and reduce the demand forsignificant U.S. force commitments to stability operations. U.S. forces will neverthelessbe ready to conduct limited counterinsurgency and other stability operations if required,operating alongside coalition forces wherever possible. Accordingly, U.S. forces willretain and continue to refine the lessons learned, expertise, and specialized capabilities
that have been developed over the past ten years of counterinsurgency and stability
operations in Iraq and Afghanistan. However, U.S. forces will no longer be sized to
conduct large-scale, prolonged stability operations.

x

Conduct Humanitarian, Disaster Relief, and Other Operations. The nation has
frequently called upon its Armed Forces to respond to a range of situations that threaten
the safety and well-being of its citizens and those of other countries. U.S. forces possess
rapidly deployable capabilities, including airlift and sealift, surveillance, medical
evacuation and care, and communications that can be invaluable in supplementing leadrelief agencies, by extending aid to victims of natural or man-made disasters, both athome and abroad. DoD will continue to develop joint doctrine and military response
options to prevent and, if necessary, respond to mass atrocities. U.S. forces will also
remain capable of conducting non-combatant evacuation operations for American
citizens overseas on an emergency basis.

The aforementioned missions will largely determine the shape of the future Joint Force. The
overall capacity of U.S. forces, however, will be based on requirements that the following
subset of missions demand: counter terrorism and irregular warfare; deter and defeat
aggression; maintain a safe, secure, and effective nuclear deterrent; and defend thehomeland and support civil authorities.

Toward the Joint Force of 2020
To ensure success in these missions, several principles will guide our force and program
development. First, given that we cannot predict how the strategic environment will evolvewith absolute certainty, we will maintain a broad portfolio of military capabilities that, in theaggregate, offer versatility across the range of missions described above. The Department
will make clear distinctions both among the key sizing and shaping missions listed aboveand between these mission areas and all other areas of the defense program. Wholesale
divestment of the capability to conduct any mission would be unwise, based on historicaland projected uses of U.S. military forces and our inability to predict the future. Likewise,
DoD will manage the force in ways that protect its ability to regenerate capabilities thatmight be needed to meet future, unforeseen demands, maintaining intellectual capital andrank structure that could be called upon to expand key elements of the force.

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6Second, we have sought to differentiate between those investments that should be madetoday and those that can be deferred. This includes an accounting of our ability to make acourse change that could be driven by many factors, including shocks or evolutions in thestrategic, operational, economic, and technological spheres. Accordingly, the concept of“reversibility” – including the vectors on which we place our industrial base, our people,
our active-reserve component balance, our posture, and our partnership emphasis – is a key
part of our decision calculus.
Third, we are determined to maintain a ready and capable force, even as we reduce ouroverall capacity. We will resist the temptation to sacrifice readiness in order to retain force
structure, and will in fact rebuild readiness in areas that, by necessity, were deemphasizedover the past decade. An ill-prepared force will be vulnerable to corrosion in its morale,
recruitment, and retention. Unless we are prepared to send confident, well-trained, andproperly equipped men and women into battle, the nation will risk its most importantmilitary advantage – the health and quality of the All-Volunteer Force.
Fourth, the Department must continue to reduce the “cost of doing business.” This entails
reducing the rate of growth of manpower costs, finding further efficiencies in overhead andheadquarters, business practices, and other support activities before taking further risk inmeeting the demands of the strategy. As DoD takes steps to reduce its manpower costs, toinclude reductions in the growth of compensation and health care costs, we will keep faithwith those who serve.
During the past decade, the men and women who comprise the All-Volunteer Force haveshown versatility, adaptability, and commitment, enduring the constant stress and strain offighting two overlapping conflicts. They have also endured prolonged and repeateddeployments. Some – more than 46,000 men and women – have been wounded, and stillothers – more than 6,200 members of the Armed Forces – have lost their lives. As the
Department reduces the size of the force, we will do so in a way that respects thesesacrifices. This means, among other things, taking concrete steps to facilitate the transitionof those who will leave the service. These include supporting programs to help veteranstranslate their military skills for the civilian workforce and aid their search for jobs.
Fifth, it will be necessary to examine how this strategy will influence existing campaign andcontingency plans so that more limited resources may be better tuned to their requirements.
This will include a renewed emphasis on the need for a globally networked approach todeterrence and warfare.
Sixth, the Department will need to examine the mix of Active Component (AC) and Reserve
Component (RC) elements best suited to the strategy. Over the past decade, the National
Guard and Reserves have consistently demonstrated their readiness and ability to makesustained contributions to national security. The challenges facing the United States today
and in the future will require that we continue to employ National Guard and Reserve forces.
The expected pace of operations over the next decade will be a significant driver indetermining an appropriate AC/RC mix and level of RC readiness.
Seventh, as we transition out of Iraq and draw down in Afghanistan, we will take extra
measures to retain and build on key advancements in networked warfare in which joint

Sustaining U.S. Global Leadership: Priorities for 21st Century Defense7forces have finally become truly interdependent. This imperative will shape a number ofDepartmental disciplines, ranging from establishing warfighting requirements to the way ourforces train together.
Finally, in adjusting our strategy and attendant force size, the Department will make every
effort to maintain an adequate industrial base and our investment in science and technology.
We will also encourage innovation in concepts of operation. Over the past ten years, theUnited States and its coalition allies and partners have learned hard lessons and applied new
operational approaches in the counter terrorism, counterinsurgency, and security force
assistance arenas, most often operating in uncontested sea and air environments.
Accordingly, similar work needs to be done to ensure the United States, its allies, andpartners are capable of operating in A2/AD, cyber, and other contested operating
environments. To that end, the Department will both encourage a culture of change and be
prudent with its “seed corn,” balancing reductions necessitated by resource pressures with
the imperative to sustain key streams of innovation that may provide significant long-term
payoffs.

Conclusion
The United States faces profound challenges that require strong, agile, and capable militaryforces whose actions are harmonized with other elements of U.S. national power. Our
global responsibilities are significant; we cannot afford to fail. The balance between
available resources and our security needs has never been more delicate. Force and program
decisions made by the Department of Defense will be made in accordance with the strategic
approach described in this document, which is designed to ensure our Armed Forces canmeet the demands of the U.S. National Security Strategy at acceptable risk.

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