Table of Contents

Since 1994, four U.S. presidential administrations have published Nuclear Posture Reviews (NPRs) that have served to—

  • clarify and publicly articulate, for domestic and international audiences, the threats that require the United States to retain nuclear weapons;
  • articulate for Defense Department personnel, Congress, and others the political leadership’s nuclear strategy and policies, including force posture, doctrine, procurement, and related infrastructure requirements;1
  • reinforce deterrence by conveying to potential adversaries how U.S. nuclear resolve and posture will augment U.S. conventional military forces and other instruments of national power in ways that adversaries cannot reasonably plan to defeat;
  • reassure allies that the United States can and will fulfill its security guarantees to them, including by means of nuclear weapons if necessary; and
  • satisfy domestic supporters of the administration while seeking to limit opponents’ opportunities to criticize it.

Past NPRs explicitly expressed the first four of these purposes but left the domestic political purposes as subtext. This approach reflects each administration’s need to simultaneously address multiple international and domestic audiences. Each of the four presidents who released an NPR did so within the first two years of their administrations, looking to shape domestic and international nuclear policy discourse for the remainder of their time in office.

The model NPR offered here presents both domestic and international contexts more directly than official NPRs have tended to do. It stresses that conventional deterrence and diplomatic prevention of conflicts (and ideally their resolution) must be a priority and that some nuclear policies and postures can make such diplomacy more or less successful. Economic power, when it is growing, can strengthen the United States’ leverage and its capacity to bolster conventional and nuclear deterrents. The perceived fairness and wisdom of U.S. policies and leaders can help build or erode international coalitions, which in turn affects adversaries’ and allies’ calculations of the balance of power and its direction. Success or failure in achieving these larger objectives can reduce or exacerbate the threats that nuclear weapons are suitable to deter or defeat.

The occasionally “meta” narrative offered here is intended to encourage holistic analysis and debate of nuclear policy challenges. Often, partisan politics, ideology, and bureaucratic and financial factors have affected nuclear policymaking as much as theories of deterrence have. Indeed, these factors influence how policymakers define or construct what nuclear postures are “necessary.” In making this narrative explicit, this model seeks to widen the range of possible policy deliberations and decisions. Similarly, it explores a wider range of policy dilemmas, uncertainties, and trade-offs than that found in public versions of official NPRs. The conclusions in this report may not please the staunchest advocates of nuclear superiority or of nuclear disarmament, but few domains of national and international governance are as beset with paradoxes and uncertainties as those in nuclear policymaking.

Few domains of national and international governance are as beset with paradoxes and uncertainties as those in nuclear policymaking.

The current moment in U.S. and international nuclear policymaking is exceptionally critical and poses new challenges. The United States and its allies and partners, along with Russia, China, North Korea, India, and Pakistan, perceive that their competitors or adversaries might be less restrained in the use of force than has been the case in recent decades, raising risks of conflict.2 Most of these countries are modernizing nuclear forces and developing and deploying new non-nuclear technologies—advanced conventionally armed missiles, terrestrial- and space-based antisatellite capabilities, and cyber weapons—that could interact with nuclear forces and their command and control systems in unpredictable ways. Each government wants to bypass its adversaries’ strengths and exploit their vulnerabilities. Each competing government says it intends to prevent or deter aggression.3 Above all, each seeks to prevail by countering its adversaries’ escalation within a conflict if deterrence efforts should fail. Yet, the ways in which governments manage these competitions may undermine deterrence and exacerbate risks of instability and escalatory conflict. The aim of this report is to stimulate current and prospective U.S. officials, foreign governments, and domestic and international civil society actors to think as holistically as possible about the choices they confront.


The authors of the 2010 and 2018 NPRs posited several objectives for U.S. nuclear policies and forces (see table 1).

Table 1: Objectives of the 2010 and 2018 NPRs
2010 NPR 2018 NPR
  • preventing nuclear proliferation and nuclear terrorism;
  • reducing the role of U.S. nuclear weapons in U.S. national security strategy;
  • maintaining strategic deterrence and stability at lower nuclear force levels;
  • strengthening regional deterrence and reassuring U.S. allies and partners; and
  • sustaining safe, secure, and effective nuclear arsenals.
  • deterrence of nuclear and non-nuclear strategic attack;
  • assurance of allies and partners;
  • achievement of U.S. objectives if deterrence fails; and
  • capacity to hedge against an uncertain future.
Sources: U.S. Department of Defense, Nuclear Posture Review (Washington, DC: U.S. Department of Defense, 2010), 17,; and U.S. Department of Defense, Nuclear Posture Review (Washington, DC: U.S. Department of Defense, 2018), 20, (hereinafter 2018 NPR).

The differences between these lists of objectives reflect changes in the international environment and in U.S. politics. The lists also reflect who led the NPR drafting process and the broader foreign policy and domestic agendas of two different presidents. Nevertheless, these lists may have more overlap and continuity than appear at first glance.

For example, the 2018 NPR downplayed references to nonproliferation. However, Donald Trump’s administration supported nonproliferation efforts and adhered to the Treaty on the Non-Proliferation of Nuclear Weapons (NPT). The 2018 NPR affirmed its predecessors’ conclusions that providing extended nuclear deterrence to allies reduces risks that they might proliferate, notwithstanding Trump’s rhetoric denigrating various U.S. allies’ contributions to their own defense.4 Similarly, although the 2018 NPR did not call for reducing the role of U.S. nuclear weapons, it did say, “The United States remains committed to its efforts in support of the ultimate global elimination of nuclear, biological, and chemical weapons.”5 The 2018 NPR, unlike the 2010 document, referred to the need “to achieve U.S. objectives if deterrence fails,” but both envisioned winning escalatory competitions with adversaries by conducting damage-limiting conventional and nuclear operations against them. Both recommended maintaining the appropriate nuclear force structure to pursue such a nuclear strategy.

In 2021, the following objectives should drive U.S. nuclear policies:

  • deter nuclear and non-nuclear existential threats to the United States and allies and partners, particularly from Russia, China, and North Korea;
  • assure allies and partners of continued U.S. commitments to mutual defense, nonproliferation, and disarmament;
  • reduce potential drivers of nuclear escalation;
  • limit the level of destruction caused by nuclear use to the lowest levels possible; and
  • preserve international stability, prevent proliferation, and facilitate nuclear weapons reductions.

These objectives reflect a shared global interest in preventing warfare, especially warfare between nuclear-armed adversaries. These objectives also acknowledge that if war nevertheless occurs, it is in everyone’s interest to limit its destructiveness. International law and, more specifically, the law of armed conflict reflect and serve these interests, as the 2010 and 2018 NPRs stated. This report will highlight the latter three of these five objectives because their policy implications deserve greater attention.


1 These elements include industrial and scientific capacity associated with nuclear weapons safety, security, effectiveness, production, and dismantlement.

2 Some scholars argue that multiple factors since World War II have caused a general decline in the number and destructiveness of international conflicts, and they argue that this decline is likely to persist. The most widely known proponent is Steven Pinker, The Better Angels of Our Nature: Why Violence Has Declined (New York: Penguin Books, 2012). See also Michael Mousseau, “The End of War: How a Robust Marketplace and Liberal Hegemony Are Leading to World Peace,” International Security 44, no. 1 (2019): 160–96. However, these theories are not uncontested; see Tanisha Fazal and Paul Poast, “War Is Not Over,” Foreign Affairs, November/December 2019,

3 Some states may consider initiating conflict as a way, in their view, to prevent an adversary from committing an aggression or territorial aggrandizement in the near future. Others likely regard such preventive uses of force as offensive rather than defensive. The U.S. invasion of Iraq in 2003 is a recent much criticized example of preemptive use of force. China’s recent behavior in and around its land and sea borders raise similar concerns of offensive behavior.

4 For example, consider Donald Trump’s comments on burden-sharing in NATO (North Atlantic Treaty Organization) and his apparent consideration of U.S. withdrawal from the Washington Treaty. Steve Holland and Lesley Wroughton, “Trump Says NATO Countries’ Burden-Sharing Improving, Wants More,” Reuters, April 2, 2019,; and Julian E. Barnes and Helene Cooper, “Trump Discussed Pulling U.S. From NATO, Aides Say Amid New Concerns Over Russia,” New York Times, January 14, 2019,; Michael R. Gordon and Gordon Lubold, “Trump Administration Weighs Troop Cut in South Korea,” Wall Street Journal, last updated July 17, 2020,

5 2018 NPR, 5.