INTRODUCTION

Abstract

The Obama administration has argued that its efforts to reduce the role of nuclear weapons in US defense policy and work toward “a world free of nuclear weapons” will encourage other governments to strengthen the nuclear nonproliferation regime and support global nuclear disarmament. Does the evidence support this assertion? This essay describes the changes in US nuclear weapons and disarmament policies initiated by the Obama administration and outlines four potential pathways through which the United States might influence other governments’ policies: by reducing nuclear threat perceptions, by changing global beliefs about what constitutes “responsible” nuclear behavior, by impacting domestic debates about disarmament in foreign capitals, and by creating new diplomatic negotiation dynamics.

Keywords:

• United States
• nuclear policy
• nuclear weapons
• no-first-use policy
• extended deterrence
• nuclear posture

The Obama administration's April 2010 Nuclear Posture Review (NPR) makes an important claim about the effect of US nuclear weapons policy on the nuclear nonproliferation policies of other states: “By demonstrating that we take seriously our NPT [Treaty on the Non-Proliferation of Nuclear Weapons] obligation to pursue nuclear disarmament, we strengthen our ability to mobilize broad international support for the measures needed to reinforce the non-proliferation regime and secure nuclear materials worldwide.”1 President Barack Obama expressed a similar view about the potential influence of US nuclear doctrine on other states’ nuclear weapons doctrines in his April 2009 Prague speech: “To put an end to Cold War thinking, we will reduce the role of nuclear weapons in our national security strategy and urge others to do the same.”2 Other high-level government officials have also referred to the international influence of the NPR. For example, Gary Samore, the White House coordinator for WMD counterterrorism and arms control, proliferation, and terrorism, noted in April 2010 that, “as we crafted the [NPR] document, [we] very consciously intended to influence the perceptions of different foreign audiences. And of course, since different foreign audiences have different interests and perspectives, the document reflects a balance in terms of how we crafted the language and the substance of the review.”3

For the Obama administration, these statements reflect a major objective of the NPR that goes beyond laying out new US doctrine for a domestic audience: the desire to affect the policies of foreign governments and the thinking of their leaders. The thesis that changes in the US nuclear posture, or even US nuclear weapons policies more generally, have a strong influence on other states’ nuclear policies is, however, quite controversial. Indeed, looking back on different historical cases, different scholars and policy makers holding divergent views on the matter.4

Does the available evidence suggest that the NPR is having the hoped-for influence on other states’ nuclear policies? If so, in what manner, by what pathway, and in which countries has the NPR influenced foreign perspectives and behavior? If not, why has the NPR not had its anticipated influence in foreign capitals? Through case studies about changes in policies and opinions in several key states, the authors in this special issue seek to identify and explain the full range of international responses to the NPR.

We did not expect the influence of the NPR to be simple, uncontested, or uniform across the countries that our authors studied. We also recognized that the NPR does not stand in isolation. Foreign governments understandably place the Obama administration's declarations about future nuclear plans and policies in the context of what specific steps the administration has actually taken on nuclear weapons; they look at what the administration has done, not just at what it has said. How can we know how foreign governments are reacting to the NPR? One purpose of this introduction is to outline possible pathways of influence that can provide a kind of lens through which observers can better interpret specific government behaviors, statements, and policy shifts. There are four possible pathways through which the NPR can have a major impact in foreign capitals. First, the NPR could influence a government's threat perception, leading it to alter its own nuclear posture, military acquisition plans, or alliance relationships. Second, US declaratory policy could change beliefs about what is appropriate and prudent behavior for responsible nuclear weapon states, and in this way the NPR could serve to promote the adoption of certain nuclear doctrines or nonproliferation norms. Third, a publicly stated shift in US nuclear doctrine could influence domestic political alignments and jockeying in foreign capitals, perhaps even empowering different decision makers to have greater influence on their government's policies. Fourth, the articulation of US interests in nuclear policy could shift diplomatic negotiation dynamics between the United States and other governments, giving some an opportunity to bargain for new benefits in exchange for policy shifts on nonproliferation or nuclear reductions.

International responses to the NPR may be difficult to observe and evaluate, in part because international reactions are likely to evolve slowly. We should not expect that governments will change their nuclear postures and policies overnight. Therefore, in this special issue, we seek to identify the early indicators of shifts that may not yet be fully implemented. Based on a theoretical understanding of influence, as well as evidence that can already be observed about state reactions to the NPR, the case-study authors make projections about what states will do with respect to nuclear policy in the future. This longer-term perspective makes it especially important for authors to seek and evaluate the full range of alternative views within a state, since opposition leaders may hold different views than current government officials, the military brass may differ in perspective from civilian leaders, and academic and media opinions may influence government policies over time. The authors therefore seek to understand not only the immediate responses to the NPR, but also the possible effects the NPR might have on future foreign policy decisions, including states’ strategic relations with the United States, support for international nonproliferation efforts, and participation in agreements such as the NPT, the International Atomic Energy Agency (IAEA) Additional Protocol (AP), or bilateral (and possibly multilateral) arms control treaties.

In this introduction, we compare the 2010 NPR to its 2001 predecessor, summarize the key nuclear posture shifts and remaining ambiguities in the 2010 NPR, outline the logic of several pathways by which US nuclear posture pronouncements can exert influence, and raise a number of questions that the following case studies seek to answer. The body of this special issue on “Arms, Disarmament, and Influence” comprises nine individual case studies on reactions to the 2010 NPR—inside the capitals of both nuclear weapon states and key non-nuclear weapon states—one case study of the NATO alliance, and one analysis of the May 2010 NPT Review Conference. In the concluding article, we summarize the case study findings and discuss further policy implications of this study of the international impact of the NPR.

The 2001 and 2010 NPRs

The 2010 NPR elevates the goals of nonproliferation, counterterrorism, and disarmament to higher prominence compared with past posture reviews, which focused primarily on how best to maintain nuclear deterrence against a range of potential threats. Under the 2010 NPR, deterrence of attacks on the United States and its allies continues to be a crucial strategic goal, but the new posture seeks to reduce reliance on nuclear weapons. The new NPR presents a considerable shift in the language and criteria for applying negative security assurances to non-nuclear weapon states. The document is also extremely well written, presenting policy positions and justifying them in clear and forceful prose. Nevertheless, the NPR also contains lingering ambiguities, namely with respect to the policy toward biological and chemical weapons (the so-called calculated ambiguity policy), the stance on preemptive and preventive use of nuclear weapons, and the role of allies in conventional deterrence.

Before turning to specific points in the 2010 NPR, it is useful to revisit its predecessor. The George W. Bush administration's 2001 NPR was not publicly released, but excerpts were leaked in early 2002.5 The report proposed a “New Triad” that would include: 1) nuclear and non-nuclear offensive strike systems, 2) active and passive defenses, and 3) a “revitalized defense infrastructure that will provide new capabilities in a timely fashion to meet emerging threats.” In the 2001 NPR, nuclear weapons were seen as providing options for deterring a “wide range of threats,” including nuclear and large-scale conventional forces. While noting that fewer nuclear weapons were needed in 2001 than during the Cold War, the report identified a significant role for nuclear weapons: “U.S. nuclear forces still require the capability to hold at risk a wide range of target types. This capability is key to the role of nuclear forces in supporting an effective deterrence strategy relative to a broad spectrum of potential opponents under a variety of contingencies. Nuclear attack options that vary in scale, scope, and purpose will complement other military capabilities.” The review also implied that existing US nuclear capabilities were not well suited to attacking deeply buried targets, such as underground leadership bunkers, and that new nuclear weapons should therefore be developed.

In outlining potential contingencies for the use of nuclear weapons, the 2001 NPR singled out several countries: North Korea, Iraq, Iran, Syria, and Libya as having long-standing hostility toward the United States; and China as having strategic objectives, ongoing nuclear modernization plans, and tensions over Taiwan that made it a potential nuclear adversary of the United States. Lastly, the 2001 review identified specific plans for the improvement of US missile defense systems, as well as plans for the development of robust nuclear earth penetrator weapons.

The tone of the 2010 NPR is a significant departure from 2001, even though not all of the new review's policy statements constitute major shifts in position. The 2010 NPR identifies two primary threats to US security: nuclear terrorism (“today's most immediate and extreme danger”) and nuclear proliferation—but it also notes the continuing challenge of “ensuring strategic stability” with Russia and China.6 The 2010 NPR lays out five key objectives for US nuclear policy:

1. Preventing nuclear proliferation and nuclear terrorism;

2. Reducing the role of U.S. nuclear weapons in U.S. national strategy;

3. Maintaining strategic deterrence and stability at reduced nuclear force levels;

4. Strengthening regional deterrence and reassuring U.S. allies and partners; and

5. Sustaining a safe, secure, and effective nuclear arsenal.7

The case studies in this special issue suggest that many states noted both the substantive and tonal shifts in the 2010 report and that most states were generally positive in their responses to the NPR. However, as discussed in the China and India case studies, the governments of some states were more critical and focused on the continuities between the 2001 and 2010 reports.

Approaches to Non-Nuclear Weapon States

The 2010 NPR's formulation of negative security assurances presents a major shift from earlier guarantees to non-nuclear weapon states. Previous negative security assurances promised that the United States would not use nuclear weapons against non-nuclear members of the NPT except “in the case of an invasion or any other attack on the United States, its territories, its armed forces or other troops, its allies, or on a State towards which it has a security commitment, carried out or sustained by such a non-nuclear-weapon State in association or alliance with a nuclear-weapon State.”8 The 2010 NPR removes these specific reservations and shifts the yardstick for judging applicability of the assurance to a state's record of compliance with its nonproliferation obligations: “The United States is now prepared to strengthen its long-standing ‘negative security assurance’ by declaring that 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.”9 Under the new formulation, if a non-nuclear weapon state that falls under the assurance—because it is in compliance with its NPT-related obligations—attacks the United States with biological, chemical, or conventional weapons, it would face a conventional, not nuclear, response.

The “not in compliance” label refers to Iran, North Korea, and possibly Syria, as was pointed out in briefings by Obama administration officials in April 2010.10 However, by not delineating a broader set of threats from particular states—as was the case when the 2001 NPR explicitly listed North Korea, Iran, Iraq, Libya, China, and Syria as threats to the United States—the 2010 version of the negative security assurance both limits the number of threatened states and suggests a path by which states can regain the guarantee. If the governments of Iran or North Korea were to abandon their nuclear ambitions and come back into compliance with the NPT, then the assurance would apply to them as well. Morton Halperin, a member of the Congressional Commission on the Strategic Posture of the United States, commented on this element of the 2010 NPR assurance:

For the first time this is a promise to those two countries, which says something we have said in a different context to the North Koreans but in my view never to the Iranians. If you come back into full compliance with the Nonproliferation Treaty, you will have a commitment from the United States not to threaten or use nuclear weapons against you, period, full stop.11

In a briefing on the NPR, James Miller, the Principal Deputy Undersecretary for Policy at the Department of Defense, expressed a similar viewpoint: “part of the rationale for the negative security assurance and its change was, in fact, to encourage North Korea to go the opposite direction and to desire to be one of those states that are compliant with their nuclear nonproliferation obligations.”12

It is important to note that the NPR does not say that the United States gives the power to judge another state's nonproliferation compliance to any international organization, as some critics erroneously suggested.13 The NPR does not detail precisely how compliance will be assessed in each case, but US officials have clarified that the United States reserves the right to judge the NPT compliance of non-nuclear weapon states. Speaking on the issue at the Carnegie Endowment for International Peace in Washington, DC, White House Coordinator for WMD Counterterrorism and Arms Control Gary Samore said that, “'in compliance with their nuclear nonproliferation obligations’ is intended to be a broad clause and we'll interpret that—when the time comes—we'll interpret that in accordance with what we judge to be a meaningful standard. … On the question of who determines, that's a U.S. national determination.”14 As noted in the case study on Egypt, the fact that the United States will make a unilateral determination of whether a state is in compliance with its nonproliferation commitments has been criticized as potentially making the implementation of the negative security assurance subject to political biases.

The new formulation of the negative security assurance is thus an important innovation in nuclear policy in three ways. First, it reduces the scenarios under which the United States is willing to threaten the use of nuclear weapons against non-nuclear weapon states, thereby reducing the role of nuclear weapons in US national security policy, as Obama promised in Prague. Second, if states are not in compliance with the NPT, then this reduced purpose does not apply and all options remain on the table. The compliance caveat therefore maintains an element of nuclear deterrence and extended deterrence for allies facing a North Korean or potential Iranian nuclear threat. Third, by establishing a pathway by which states might lose or regain their qualification for the guarantee, the 2010 NPR provides an incentive that might influence the decision making of governments of current or potential proliferators considering a shift in their nuclear policies either away from or toward nuclear weapons.

Approaches to Nuclear Weapon States

There is more limited innovation in the 2010 NPR with regard to nuclear posture aimed other nuclear weapon states, particularly Russia and China. Significantly, the NPR calls for ratification of the Comprehensive Nuclear-Test-Ban-Treaty (CTBT) and supports additional mutual nuclear reductions, as well efforts to increase stability and transparency in strategic relationships with these two states. The NPR specifically calls for further discussion on nuclear reductions after the ratification of New START, conceiving the treaty as a step toward nuclear disarmament. An ongoing strategic dialogue could lead to Russia sharing more information about its modernization programs and being willing to discuss US concerns about its nonstrategic nuclear arsenal.15 Plans for reductions will be balanced with the need to assure US allies who rely on the extended deterrent for their security. The NPR makes clear that the Obama administration hopes that Russia, and eventually China, will be willing to participate in deeper nuclear reductions, and that the United States sees these negotiations as a key priority for the future.

More stable strategic relationships with Russia and China, including greater communication, will, it is claimed, improve transparency, decrease mistrust, and increase confidence. The NPR explicitly posits a desired outcome in this evolution of relations:

Building more stable strategic relationships with Russia and China could contribute to greater restraint in those countries’ nuclear programs and postures, which could have a reassuring and stabilizing effect in their regions. It could also facilitate closer cooperation by those two countries with the United States on measures to prevent nuclear proliferation and nuclear terrorism.16

In its approach to nuclear weapon states, the 2010 NPR thus suggests an important hypothesis: a more cooperative atmosphere on bilateral nuclear issues with Russia and China will produce increased cooperation on broader global nuclear security issues. In this case, the document assumes that improved US-Russian and US-Sino strategic relations will make it more likely that Moscow and Beijing will cooperate with Washington's other nonproliferation and counterterrorism efforts. To what extent we can observe this is therefore a crucial question for the case studies in this special issue.

The 2010 NPR places China in the same category with Russia, rather than with rogue states or enemies of the United States.17 In the 2001 NPR, China was explicitly mentioned as one of the states against which the United States would consider conflict contingencies using nuclear weapons; “a more cooperative relationship” was mentioned for Russia, though clearly Russia was still targeted in US war plans.18 In contrast, the 2010 NPR states that, “The United States and China are increasingly interdependent and their shared responsibilities for addressing global security threats, such as WMD proliferation and terrorism, are growing.”19 In the 2010 NPR, China is treated as a key nuclear player that the United States can work with on issues of strategic stability, and the language stresses cooperation and mutual interests.

Across the Board

The NPR also makes several shifts that apply to both nuclear and non-nuclear weapon states. For example, the threat of nuclear terrorism is more prominent in the 2010 NPR and is mentioned as the most urgent security threat alongside proliferation and strategic stability.20 The concepts are linked, with preventing nuclear terrorism identified as the ultimate goal: “U.S. arms control and disarmament efforts, as well as other means of reducing the role of nuclear weapons and moving toward a world without them, can make a major contribution to our goal of preventing nuclear proliferation and nuclear terrorism.”21 Encouraging international participation in counterterrorism efforts is thus a key way in which the NPR hopes to influence policies in other states.

Perhaps the most significant change, however, is the NPR's attempt to reduce the role of nuclear weapons in security policy. The NPR states, “The fundamental role of U.S. nuclear weapons, which will continue as long as nuclear weapons exist, is to deter nuclear attack on the United States, our allies, and partners.”22 This statement is a shift from the 2001 NPR, in which deterring chemical and biological weapons was also identified as a crucial and indeed “unique” role for nuclear weapons.23 Nevertheless, “fundamental role” does not mean “only role,” so the current posture does include other possible roles for nuclear weapons. The 2010 NPR explicitly states that moving toward a posture in which nuclear weapons have the “sole purpose” of deterring nuclear attack is a goal for the future: “The United States is therefore not prepared at the present time to adopt a universal policy that the ‘sole purpose’ of U.S. nuclear weapons is to deter nuclear attack on the United States and our allies and partners, but will work to establish conditions under which such a policy could be safely adopted.”24

Even in cases where nuclear weapons might be used under this doctrine, such as in a conflict with a nuclear weapon state or a state that is not in compliance with nonproliferation obligations, there are now only a “narrow range of contingencies in which U.S. nuclear weapons may still play a role in deterring a conventional or CBW attack,” as opposed to the “wide range of threats” referenced in the 2001 NPR.25 While the 2001 NPR referred to nuclear weapons having “unique properties that give the United States options to hold at risk classes of targets,” the 2010 NPR suggests that most threats can be met with conventional capabilities.

It is important to note that although the 2010 NPR does not say that the United States will seek to establish a no-first-use (NFU) posture in the future, the goal of having the sole purpose of US nuclear weapons be deterring other states’ nuclear weapons use is essentially the same doctrine with a more politically correct label. Indeed, as the International Commission on Nuclear Non-proliferation and Disarmament, a joint Japanese/Australian initiative, noted in 2009, a declaration that “the sole purpose of the possession of nuclear weapons is to deter the use of such weapons against one's own state and that of one's allies” is “a different formulation of essentially the same idea” as NFU.26

The brief discussion of “sole purpose” in the 2010 NPR, however, raises several questions about international perceptions of NFU-type policies. Would a future US sole purpose declaration be seen as credible by other states? What other US doctrinal or operational changes would make a sole purpose declaration more credible for other states? What do non-nuclear US allies believe such a declaration would imply for extended deterrence? If the United States were to adopt a sole purpose declaration, would other nuclear states follow suit?

Lingering Ambiguities

In addition to highlighting some of the more straightforward features of the NPR, it is also valuable to identify the report's ambiguities. While of relatively minor importance in comparison with the key new innovations in the NPR, the lingering ambiguities may be particularly salient to some key states, including those covered in this special issue. Three examples of ambiguity in the 2010 NPR are worth highlighting.

First, the NPR is unclear on the role of allies in providing for greater future reliance on conventional deterrence. The NPR states that the United States will increasingly rely on conventional means to deter attacks, including biological, chemical, and conventional threats against both the United States and US allies. The NPR mentions allies’ conventional capabilities and their ability to defend against conventional regional threats as a change in the post–Cold War strategic situation, but the report does not indicate what specific role allies will play in strengthening regional conventional capabilities, or US ability to project those capabilities.27 The NPR's sections on regional deterrence focus on US plans and on capabilities the United States has or will pursue, with little mention of how the United States might expect allies to contribute to these efforts.28 Specifically with respect to European allies, the NPR leaves questions about the role of US nuclear weapons in Europe for future NATO discussions; with respect to allies in the Pacific, the NPR leaves the details to be worked out in regional defense planning forums.

It will be valuable to determine, therefore, how allies have responded to requests to have more “tailored” forms of extended nuclear deterrence and how key allies envision their role in improving conventional deterrence. Do they worry about or welcome a shift to greater reliance on alliance conventional capabilities to deter aggression? Do they seek to keep open their own nuclear weapons options in the long term to protect themselves from the possible withdrawal of US security guarantees, or do they see increased efforts to enhance conventional deterrence as part of their NPT Article VI commitments to work in good faith toward nuclear disarmament?29

The 2010 NPR rules out preventive and preemptive use of nuclear weapons for non-nuclear weapon states in compliance with their nonproliferation obligations, but there is no direct discussion of preventive or preemptive use against nuclear weapon states or NPT violators. President George W. Bush left open the possibility of a preventive nuclear strike against Iran in April 2006 when he dramatically repeated that “all options are on the table” after being specifically asked if his policy included nuclear options to destroy Iran's nuclear facilities.30 Whether the Obama administration means to keep in or rule out preventive nuclear weapons options against Iran is not clear. However, it is clear that Iran's leaders continue to interpret US statements about options, including the 2010 NPR, as a nuclear threat.31

Lastly, some commentators have interpreted the NPR's language on biological weapons as ambiguous because it appears to include a possible caveat.32 The text in question in 2010 NPR states:

In making this strengthened assurance, the United States affirms that any state eligible for the assurance that uses chemical or biological weapons against the United States or its allies and partners would face the prospect of a devastating conventional military response—and that any individuals responsible for the attack, whether national leaders or military commanders, would be held fully accountable. Given the catastrophic potential of biological weapons and the rapid pace of bio-technology development, the United States reserves the right to make any adjustment in the assurance that may be warranted by the evolution and proliferation of the biological weapons threat and U.S. capacities to counter that threat.33

One way to interpret this statement is that it allows the United States a way out of existing negative security assurances. We note, however, that the statement identifies a future right to evaluate the situation. As such, the statement is more of a marker and less of a caveat. This marker indicates that while today's promise to not use nuclear weapons against biological weapons should be taken seriously, in the future it might be necessary to reevaluate and, if needed, publicly change that promise. The promise to assess and adjust nuclear doctrine if necessary is not, however, intended to imply a lack of commitment to current doctrine and new negative security assurances.

International Responses to the 2001 NPR

In summarizing the 2010 NPR, we have raised several questions on how states might respond to shifts and ambiguities in US policy, but it is also interesting to consider international responses not only across country cases, but also over time. How do responses to the 2010 NPR differ from international responses to the 2001 NPR? A 2006 SAIC report, “Foreign Perspectives on U.S. Nuclear Policy and Posture,” provides a good overview of responses to the 2001 review; furthermore, many of the reactions are directly related to the shifts we identify in the 2010 review.34 The SAIC study found that most states (including key US allies) criticized the 2001 NPR for increasing the role of nuclear weapons, blurring the line between conventional and nuclear weapons, and making nuclear weapons more usable. Numerous international sources, including those among allies and friends, expressed concern that an NPR that gave the impression of an increased nuclear role would have “possible adverse proliferation impacts.”35 Some states perceived a threat in US plans to develop new nuclear weapons, namely nuclear bunker busters, while at the same time US allies saw these plans as largely unnecessary for security. Many allies—including Japan, Turkey, Australia, and new NATO members—continued to see a need for extended deterrence in general, but there was less support from “Old NATO.”

The SAIC report found that many countries, particularly US allies, criticized the relatively closed process by which the 2001 NPR was developed. They argued that the US government needed to have much deeper consultations with allies before drafting a new posture and needed to be better about listening to the allied perspectives. The SAIC report therefore recommended that the United States consult more frequently, address disagreements and clarify misconceptions more carefully, and communicate its plans more clearly. In fact, six out of the ten broad implications in the report are essentially about communication regarding US intentions and US responses to other states’ concerns.36 The report also called for US officials to rethink their approach to disarmament by reaffirming the elimination of nuclear weapons as a US goal and by engaging in the disarmament debate. The SAIC study identified a clear recommendation from US allies that links the US approach to disarmament to influencing the policies of other states: “from close U.S. allies, their final message for U.S. officials is that a greater U.S. readiness to engage on nuclear disarmament issues would pay off in increased support from other third parties in pursuing U.S. non-proliferation objectives.”37

The dominant international reactions to the 2001 NPR were deep concern about the apparent increased role of nuclear weapons in US doctrine and hesitant support, from US allies only, for new developments such as missile defense and improved long-range conventional weaponry. Even though in some respects the 2010 NPR does not make drastic shifts from its predecessor, or establish a sole purpose for nuclear weapons as some experts hoped, it does adopt a significantly different tone on nuclear policy, stressing international cooperation in reducing nuclear dangers and limits for US weapons. Additionally, the 2010 NPR was developed through extensive consultations with US allies. Did the same states that criticized the 2001 NPR have a more positive response to the 2010 NPR? Do states interpret the document and the consultation process as enough of an engagement on disarmament to warrant supporting the United States on its nonproliferation goals?

A central purpose of our case studies is to determine the degree to which there is in fact a connection between US promises and progress regarding disarmament and other states’ policies regarding nonproliferation efforts. In this special issue, the case studies provide new evidence in an ongoing debate that has emerged in the context of the 2001 NPR, the 2010 NPR, and US nuclear policy more broadly. Harald Müller's article on the 2010 NPT Review Conference is particularly important as an early test of the proposition. Taking place directly after the release of the NPR, the NPT Review Conference presented an opportunity to observe states’ rhetoric on nonproliferation and disarmament issues and, more importantly, their behavior in negotiations.

In trying to assess whether disarmament and support for nonproliferation are related, or whether a US move to limit the role of nuclear weapons leads other states to do the same, we need a better sense of, essentially, what to look for as indicators. We turn to this question in the next section, connecting the indicators we should look for in country responses with the processes by which we might expect influence to occur.

The NPR and Theories of Influence

The 2010 NPR policy statements summarized above are intended not only as a domestic declaration of the new US nuclear posture, but also as a tool to influence the behavior of other states. Despite making this goal clear in the NPR and in other key statements, however, the Obama administration has not provided an explanation of how it believes such influence actually happens. Why should we expect what the United States says about its nuclear weapons to have an impact on nuclear decision making in other states? What precisely happens when foreign governments observe a US declaratory policy that encourages, incentivizes, or compels them to adjust their own approach to nuclear weapons?

To better understand the possible pathways of policy influence, we turn to several theories about diplomatic influence from the political science literature and elaborate on their application for nuclear posture. The four approaches proposed below—changing threat perceptions, creating norms of appropriateness and legitimacy, enabling domestic actors, and altering bargaining dynamics—are “ideal pathways” in the sense that they provide a model lens we can apply in interpreting observed behaviors of states. While it is possible that one pathway may provide a better explanation for how influence occurs in one or many states, these pathways are not mutually exclusive, and it is possible that several pathways work simultaneously, or perhaps under different conditions. While these theories can help us frame existing evidence and suggest new directions for inquiry, we also expect that some of the observations in the following case studies will not fit neatly into any of these ideal types.

Changing Threat Perceptions

One strand of realist theory emphasizes that, first and foremost, states care about their security, and they must respond to changes in their security environment. States change their own nuclear policies to suit new security needs, such as in response to a new threat from the United States or a regional challenger or a reduction in such threats. In response to a new threat, states might pursue policies such as enhancing their own capabilities, creating hedging options regarding nuclear proliferation, or seeking to strengthen an alliance.38 From this point of view, the mechanism by which the NPR influences policy change in other states is in the way that US declaratory policy informs their assessments of national security needs.

If we believe that threat assessment is a key driver of a state's nuclear policies, then we would want to know how particular elements of the NPR affect threat perception in that state. In some cases, the NPR affects the threat perception of other states because these states perceive themselves to be targets of US weapons or see US weapon developments as an attempt to neutralize their own capabilities. For example, if China were to interpret US plans for missile defense as directly intended to overcome Chinese capabilities, then that threat assessment might affect Chinese arms development programs. Alternatively, some US shifts, such as the new formulation of negative security assurances, may make the governments of non-nuclear weapon states feel less threatened by US nuclear weapons than they were previously, in which case they may seek to shift resources away from domestic armament programs or support strengthened nonproliferation policies (such as the IAEA's Additional Protocol) that constrain their future options. The NPR articulates this logic several times, in terms of both nuclear and non-nuclear weapon states.39

Responses to the NPR based on threat perceptions can also be difficult to predict. The 2010 NPR attempts to reduce the role of nuclear weapons, but this shift has the potential to make foreign governments feel either more or less threatened. On one hand, states that are not threatened by nuclear weapons might be less likely to seek a nuclear deterrent of their own. But US plans to develop certain conventional capabilities—namely, Prompt Global Strike (conventionally armed land- or sea-based intercontinental ballistic missiles)—may lead some states to perceive an increased threat from the United States if they believe that these conventional weapons are more likely to be used than nuclear weapons. This perception may alter their calculations for the kinds of deterrence postures and capabilities they need to respond to US developments. As another example, we might ask whether allies that rely on the US extended nuclear deterrent still assess their security as being adequately guaranteed by the United States even with a more limited nuclear mission. Under what conditions might these allies question the adequacy of US protection and respond by bolstering their security in other ways, such as through domestic conventional or even nuclear programs? There have been persistent concerns, for example, about whether US efforts to reduce the role of nuclear weapons for extended deterrence in South Korea and Japan will undercut perceptions in Seoul and Tokyo of the credibility of US security guarantees. Alternatively, such efforts might enhance South Korean and Japanese perceptions that the United States is committed to their security because conventional responses to attacks other than nuclear attacks on allies could be deemed to be much more likely and therefore a more credible deterrent threat in the first place.

A critic of this approach to understanding the effects of changing nuclear postures could raise an important counterargument: why should what the United States says it will do matter for other states? Why would other governments believe that the NPR is a credible signal? After all, the term “declaratory policy” is sometimes used to differentiate between what a government says about its nuclear weapons and what a government really plans or intends to do with its arsenal. Moreover, the US government could choose to not follow NPR statements or just change plans when it becomes advantageous to do so. If the information coming from US declaratory policy is not seen by states as a credible indicator of actual changes in US plans, behavior, and capabilities, we would not expect the NPR to have any influence on their decision making.

In our judgment, this criticism is not sound, and it would be a mistake to dismiss the potential of the NPR to influence others for two central reasons. First, the NPR is not as “cheap” a signal as it might appear. There are costs associated with declaratory statements that can help make them appear as more credible commitments by the US government to a certain future policy. Once a posture change is announced and defended publicly by the administration, President Obama would face criticism from domestic and international audiences if he were to back away from an announced position.40 Costs also come from inside the government, as the declaratory policy informs classified military guidance. Both senior and junior US military officers often refer to declaratory policy in developing more specific planning, so while publicly stated and classified doctrines may differ in some respects, they are rarely inconsistent.41 Again, if a significant inconsistency between public and classified nuclear postures were ever exposed, the administration would risk political costs and charges of hypocrisy. Second, even if there are questions raised about the reliability of the posture signaled through the NPR, the document still provides some information about US intentions and strategy. As a consequence, states will try to evaluate the extent to which policies declared in the NPR will translate into capability or posture shifts. The fact that the NPR can present ambiguous signals about US policy shifts means that states may misinterpret the direction, or conduct additional analysis of US policy, but it does not imply that there would be no response at all to the document.

The “threat perception” pathway suggests several kinds of possible responses from observer states that we would be able to interpret as NPR influence. In each country, we would want to know to what extent government officials are focused on assessing the meaning of the NPR for future US capabilities. Do they explicitly look to the NPR to inform their discussions on US capabilities, posture, or plans for future developments? On the other hand, do some actors, such as military officials, dismiss the NPR as not credible, or simply ignore it? Such a finding would suggest that the NPR is not having an impact on certain states’ threat perceptions. In some scenarios, we might not be able to observe the changing threat perceptions, but rather the resulting policy changes. If states are seen changing their own nuclear or conventional postures, starting or stopping some defense programs, or strengthening an alliance after the 2010 NPR, we might see these as threat perception–based responses to the US policy. Finally, how do states respond to specific elements in the NPR that are intended to alter their security calculations? For example, how is the shift in negative security assurances perceived by non-nuclear weapon states? Do nuclear weapon states agree that greater stability in strategic nuclear arsenals will allow for more cooperative relations in other security areas?

Norms of Appropriateness and Responsibility

A second way in which the NPR may influence other states is through the establishment and promotion of international norms.42 Through public statements, the United States shapes common understanding of what it means to be a “responsible” state, what “leaders in nonproliferation” do, and how “leading powers” behave.43 The role and identity of a responsible nuclear state are increasingly defined via participation in arms control negotiations, nonproliferation and export control organizations, and efforts to limit the role of nuclear weapons. Declaratory policies like the NPR contribute to US efforts to create a consensus around this definition of appropriate behavior and best practices, while creating rules to identify outliers—states whose behavior makes them violators and irresponsible actors.44

We can observe the norm-based influence of past US declaratory policies most clearly in India's nuclear doctrine shifts. In 1999, the Draft Indian Nuclear Doctrine proposed a formulation on conditions for nuclear use that was an almost identical copy of language in US negative security assurances from the 1980s: “India will not resort to the use or threat of use of nuclear weapons against states which do not possess nuclear weapons, or are not aligned with nuclear weapons powers.”45 Following the 2001 NPR, in 2003 the Indian government changed its traditional NFU nuclear doctrine to include the threat of nuclear first use against a state that uses biological or chemical weapons against Indian territory or its armed forces anywhere.46 This apparent mirroring of not only US policy but also language suggests that US declaratory policy informed another government about what policy shifts were appropriate and how best to articulate them. India's National Security Advisory Board served as a kind of “engine of isomorphism,” bringing ideas from the US 2001 NPR into doctrinal debates in New Delhi and advocating the US doctrinal innovations as prudent, appropriate actions for adoption in India.47

How do norms and definitions the United States supports become internationalized, transferring from external ideas to domestic policies? Political scientists have suggested several mechanisms for “norm diffusion.”48 First, because the United States is a powerful state, its adoption of certain norms and appropriate behavior understandings makes them more prominent in the eyes of observer states. Norms that appear more prominent and widespread are more likely to be adopted by other states as well. Second, if the United States is seen as a leader in some issue area, and US policy is seen as reasonable rather than hypocritical, then this position gives the United States the ability to legitimate certain existing ideas. Norms that have legitimacy are more likely to be widely adopted than other ideas or understandings. The ability of the United States to give some norms greater prominence and legitimacy in the international system means that these ideas will be more likely to influence the nuclear policies of other states.

The NPR alludes to a norms-type influence mechanism on several occasions. Most explicitly, it refers to North Korea and Iran as defying “international norms and agreements” on the proliferation of nuclear weapons. As a result, the NPR maintains, these states will face increasing isolation and international pressure.49 The NPR further argues that reducing the role and number of nuclear weapons demonstrates that the United States is making progress toward meeting its NPT Article VI obligations, which puts it in a “much stronger position to persuade our NPT partners to join with us in adopting the measures needed to reinvigorate the non-proliferation regime and secure nuclear materials worldwide against theft or seizure by terrorist groups.”50 This point suggests the United States seeks a position that will give its objectives greater international legitimacy, increasing the chances of broader adoption. Finally, there is also a hope in the NPR that other states may emulate future US policy choices, such as ratifying the CTBT if the United States were to do so.51

As with the threat perception explanation, we can imagine a number of possible state responses that we might interpret as evidence of norms diffusion. First, does domestic debate in these states explicitly reference pressure from a “nonproliferation norm”? Does the state try to identify itself as a responsible member of the nonproliferation regime? Are government officials more likely to repeat language similar to the NPR's in their own discussions on issues such as role of nuclear weapons, nuclear posture, or nuclear terrorism and proliferation threats? Is there increased support for the United States in public forums, such as the NPT Review Conference?52 The norms explanation suggests that we evaluate not only national security policy shifts in observer states, but also their behavior in international forums and even their rhetoric in public discussions of nuclear issues.

Domestic Actors as an Intervening Factor

The policies that the United States adopts create opportunities and incentives for various domestic actors in other countries to participate in debate, which in turn mediates how receptive the state's policy is to altered threat perceptions or changing norms. Rather than a separate influence mechanism, domestic politics is likely to be an important intervening factor, altering the impact of the two influence pathways discussed above.

By turning some issues—such as nuclear reductions or counterterrorism efforts—into prominent topics of international discussion, the NPR can give certain actors a new opportunity to participate in policy debates. US support for the CTBT or for clearer negative security assurances, for example, elevates the positions of officials responsible for these policy issues in other countries. These officials play a more prominent role as the United States seeks to start bilateral negotiations, hold multilateral meetings, or put these issues on international forum agendas. The increased presence of these actors, who already hold preferences for new policy directions, may make the government more amenable to reevaluating the security environment or adopting nonproliferation norms.53 President Obama's 2010 Nuclear Security Summit, for example, was clearly designed to elevate the attention given to physical protection of nuclear materials outside the United States by bringing more than forty heads of state to Washington and having them agree to meet again in Seoul in 2012.

International responses can shift in both pro-US and anti-US directions, however, depending on how US policies are interpreted and presented to domestic audiences by key government players. The “domestic factors” pathway therefore also suggests that foreign interpretations of the NPR could be “deliberate misinterpretations” designed to promote certain policy preferences. The content of the NPR could be intentionally misrepresented, for example, by groups that seek a greater role for nuclear weapons and that use US policy to generate public support for their cause.

In individual country cases, the role of domestic actors might be observed when comparing the NPR responses of various domestic groups. Are views among different groups similar or different? What is the nature of disagreements between groups? Going further, it is important to consider who participates in discussions before and after the 2010 NPR. Are there new actors becoming involved in nuclear policy discussions, or perhaps some old actors who are now more, or less, prominent? It is also possible that some responses to the NPR are articulated because they are salient for domestic audiences. Do some actors stand to benefit or suffer from domestic public views on nuclear issues? Do we see these actors leveraging such issues in political statements or electoral campaigns? Finally, in each country case, we would want to evaluate how new actors or domestically salient issues might impact the state's perspective on changing security threats or on the state's receptiveness to nonproliferation norms.

Creating a Bargaining Dynamic on Nonproliferation Policies

The fourth and final way in which the US nuclear posture can influence other states is not though precipitating changes within those states, but rather in altering the way these states can bargain with the United States over benefits and concessions in security or even economic negotiations. The NPR identifies what nuclear policies the United States wants other states to adopt, key areas where it hopes to have international participation in nonproliferation efforts, what kinds of future reductions it is interested in, and which outlier states it hopes to pressure into compliance. This information could give foreign governments an opportunity to come to the bargaining table with newly valuable offers. For example, states might be more willing to offer new support for sanctions on another state, take steps toward ratifying the CTBT, or give support to the IAEA's AP, because they see these as policy moves that the United States wants and therefore would be willing to reward, directly or indirectly. Some research suggests that such implicit bargains have long been present in nuclear-related negotiations; Jennifer Erickson and Christopher Way, for example, find that states that signed the NPT have statistically significant higher levels of conventional arms transfers from Washington and Moscow, even controlling for patterns of alliance commitments.54

A new bargaining space in nuclear policy could also lead some states to hold out on policy shifts because they hope to get a better concession from the United States. Because the NPR reveals what is valuable to the Obama administration, some governments might actually be less likely to support a US-led nonproliferation effort without a better trade in return, even though previously they might have been just as willing to go in that direction anyway. For example, Russia might withhold its support for multilateral pressure on Iran until it receives concessions from the United States in other areas, for example in bilateral arms control, in US missile defense plans, or even in US relations with key third-party states such as Ukraine, Georgia, or Uzbekistan.

Evidence of NPR influence through bargaining dynamics can be difficult to observe because trade-offs are often not explicit “deals,” especially across issue areas. However, linkages are a common aspect of foreign policy, and in hypothesizing that some bargaining dynamic is going on specifically within the nuclear sphere, we can look for which policy shifts might be related. Considering the timing of decisions may be particularly useful. Are there some policy shifts that states seem more willing to make post–2010 NPR than they were previously? Are they also expecting increased support or other benefits from the United States, including in other non-nuclear issue areas? Are some states less willing to participate in the reduction and nonproliferation goals laid out in the NPR than they were previously? Are these states making stronger demands, or trying to draw out a negotiation process with the United States?

A Few Important Caveats in Using a Theoretical Lens to Understand Responses

The influence pathways we have presented are not mutually exclusive, and it is possible that the NPR actually influences other states though several or even all of these mechanisms. The degree of policy influence can range across country types, the direction of that influence might vary, and responses to the NPR might be stronger in some countries than in others, even though some element of influence occurs in all. The effect of US declaratory policy likely varies by the nuclear status of observer states.

Additionally, some influence pathways may apply well to one group of states but be less applicable to another. For example, accepting the US understanding of “appropriate behavior” in the nuclear sphere might be more likely with states that are already closely aligned to the United States ideologically or politically than it is for states with existing tensions or entrenched views on disarmament serving as competing norms to US views. We might also expect that certain parts of the NPR will draw stronger responses from some states than others. The effect of declaratory policy likely varies based on how clear that policy is perceived to be by observer states. Clear statements may engender strong international responses, while ambiguities may lead to mixed responses or hedging.

These likely divergences in responses are in part related to the point that as a policy statement, the NPR is intended for multiple audiences, including multiple types of international actors as well as domestic constituencies in the United States. For example, the NPR seeks to balance a range of needs and expectations from US NATO allies, some of whom have strong preferences for disarmament (like Germany), while others remain committed to their own nuclear weapons (such as France), or US weapons for extended deterrence (such as Turkey). Domestically, the NPR must also address both parties in Congress, especially some Democratic advocates of nuclear disarmament and some Republican members who are particularly attentive to the future of modernization programs. Given this need to balance interests, the NPR's message may in some cases be intentionally ambiguous, leading to multiple reasonable interpretations by international actors.

Finally, to reiterate a point from the beginning of this introduction, we must be mindful of the fact that change takes time. Some of the observations on state responses presented in the case studies are early indicators of new policies, and some may turn out not to be indicative of future shifts. In looking at observable evidence of the ideal-type pathways, our goal is to identify what we assess as supporting or disconfirming evidence of policy influence, both at the time of this analysis and in future expectations. In this special issue, we seek to make some projections about how reactions to US nuclear policy might continue to unfold in other states; it is also important to consider what kinds of future international responses would suggest that these projections are, or are not, bearing out.

Conclusion—What this Issue Contains

The articles in this special issue report on a considerable range of international responses to the NPR, including overall positive reactions along with some negative ones, relief from some states that the NPR does not go too far toward disarmament (and concern that it does not go far enough from others), and evidence of foreign governments’ policies that shifted in response to the NPR and of policies that largely ignore US attempts at influence. The case studies cover multiple types of states: authors investigate responses from nuclear and non-nuclear weapon states, NPT members and non-members, close and distant US allies, and states facing different types of threat environments. This collection of case studies thus allows us to capture a wide range of reactions to the NPR.

The countries studied here were selected not only for the analytic range they provide, but also by merit of their individual importance. Japan, for example, is not merely representative of the group of non-nuclear, NPT-member, close-US ally states. Japan's geostrategic position and advanced civilian nuclear capabilities make it a particularly important case for understanding the role of US security guarantees in affecting the nuclear decisions of other states. China and Russia are essential to any discussion of international responses to the NPR because they are the two nuclear powers that could be targets of US offensive nuclear capabilities. However, some key countries were omitted from this project. As states in noncompliance with the NPT, Iran and North Korea are actors the United States particularly wants to affect, but which are also likely to be the hardest targets of influence. Further analysis of international responses to the NPR would benefit from both assessment of longer-term responses of the cases included here, as well as inclusion of additional cases.

Finally, as the case studies make clear, the influence of the NPR should be assessed within the context of other factors shaping states’ long-term behavior. The NPR is one element of the broader US nuclear agenda, and most case studies in this issue explicitly note that states connect the NPR with expectations from President Obama's Prague speech. As we will note in the concluding article, the influence of the US NPR does not take place in isolation from other US policies. We should conceive of US progress on the disarmament front, these case studies suggest, as a necessary, but not sufficient, condition for international progress on the nuclear nonproliferation agenda. The NPR could not guarantee that other governments would react in the manner that the United States wished in the arena of nuclear nonproliferation policies, but it did make it more likely that reasonable compromises and mutually acceptable agreements could be negotiated.

ACKNOWLEDGEMENTS

We thank Paul Brest, Megan Garcia, and Emily Warren of the Hewlett Foundation for supporting this project. We also thank Michael Armacost, Linton Brooks, Lewis Dunn, John W. Lewis, Michael May, Vipin Narang, Gi-Wook Shin, and Michael Sjulin for their valuable comments on earlier drafts of the articles in this special issue. Finally, we want to acknowledge the superb research and editing support provided by Jane Esberg from the genesis to the completion of the project.

Notes

1. Department of Defense, “Nuclear Posture Review Report” (hereafter 2010 NPR), April 6, 2010, p. 12, <www.defense.gov/npr/docs/2010%20nuclear%20posture%20review%20report.pdf>.

2. Barack Obama, “Remarks by President Barack Obama,” Prague, April 5, 2009, <www.whitehouse.gov/the_press_office/Remarks-By-President-Barack-Obama-In-Prague-As-Delivered/>.

3. Gary Samore, remarks at “International Perspectives on the Nuclear Posture Review,” Carnegie Endowment for International Peace, Washington, DC, April 22, 2010, <www.carnegieendowment.org/files/0422carnegie-samore.pdf>.

4. For a good outline of this debate, see Christopher F. Chyba, “Time for a Systematic Analysis: U.S. Nuclear Weapons and Nuclear Proliferation,” Arms Control Today, December 2008, <www.armscontrol.org/act/2008_12/Chyba>. On the argument that there is no causal connection between disarmament and proliferation, see Harold Brown and John Deutch, “The Nuclear Disarmament Fantasy,” Wall Street Journal, November 19, 2007, p. 9; and Christopher Ford, “Disarmament vs. Nonproliferation?” New Paradigms Forum, October 29, 2010, <www.newparadigmsforum.com/NPFtestsite/?p=531>. For an argument on how US nuclear policies can influence other states, see Christopher F. Chyba, “Remarks at Carnegie International Non-Proliferation Conference, Washington DC, June 22, 2004, <cisac.stanford.edu/publications/us_nuclear_posture/>.

5. Quotes in this paragraph are from the 2001 NPR. Excerpts from the 2001 NPR (submitted to Congress on December 31, 2001), are available at GlobalSecurity.org, “Nuclear Posture Review [Excerpts]” (hereafter 2001 NPR), January 8, 2002, <www.globalsecurity.org/wmd/library/policy/dod/npr.htm>.

6. 2010 NPR, p. iv (Executive Summary).

7. 2010 NPR, p. iii.

8. “U.S. ‘Negative Security Assurances’ at a Glance,” Arms Control Association, Fact Sheet, 2010, <www.armscontrol.org/factsheets/negsec>.

9. 2010 NPR, p. 15. We interpret “nuclear nonproliferation obligations” as referring to those obligations arising from NPT membership. This interpretation is consistent with comments on the NPR negative security assurance by Obama administration officials. For example, at the NPR rollout event in April 2010, Secretary of Defense Robert Gates articulated the assurance as: “If a non-nuclear-weapon state is in compliance with the nonproliferation treaty and its obligations, the U.S. pledges not to use or threaten to use nuclear weapons against it.” Robert Gates, remarks at “DOD News Briefing with Secretary Gates, Navy Adm. Mullen, Secretary Clinton, and Secretary Chu,” Pentagon, Washington DC, April 6, 2010, <www.defense.gov/transcripts/transcript.aspx?transcriptid=4599>.

10. Robert Gates, remarks at “New Nuclear Posture Review Briefing,” Pentagon, Washington, DC, April 6, 2010, <www.jcs.mil/speech.aspx?id=1355>. On Syria being a case of noncompliance that has not been resolved, see Samore, remarks at “International Perspectives on the Nuclear Posture Review,” p. 5.

11. Morton Halperin, comments at briefing on “Understanding New START and the Nuclear Posture Review,” Arms Control Association, Washington, DC, April 9, 2010, <www.armscontrol.org/events/STARTandNPRBriefing>.

12. James Miller, comments at “DOD's Nuclear Posture Review Rollout Briefing,” Department of Defense, “Officials Brief on the Department of Defense's Nuclear Posture Review: US Seeks to Reduce Nuclear Dangers, Pursue World Free of Nuclear Weapons,” April 7, 2010, <www.america.gov/st/texttrans-english/2010/April/20100407165508xjsnommis0.7896016.html&distid=ucs>.

13. For example, Keith Payne, a former Department of Defense official, said: “The new NPR appears to place the UN's IAEA and its Board of Governors at the heart of determining U.S. nuclear deterrence strategy options,” quoted in Bill Gertz, “Inside the Ring: U.N. Nuclear Control,” Washington Times, April 8, 2010, <www.washingtontimes.com/news/2010/apr/08/inside-the-ring-49434836/>.

14. Samore, remarks at “International Perspectives on the Nuclear Posture Review.”

15. 2010 NPR, p. x (Executive Summary).

16. 2010 NPR, p. x (Executive Summary), p. 29.

17. The 2010 NPR includes a section titled “Strategic Stability with Russia and China,” on pp. 4–5.

18. 2001 NPR, section titled “Sizing the Nuclear Force,” in which China's capabilities are mentioned in the context of US force requirements: “In setting requirements for nuclear strike capabilities, distinctions can be made among the contingencies for which the United States must be prepared. Contingencies can be categorized as immediate, potential or unexpected. … Due to the combination of China's still developing strategic objectives and its ongoing modernization of its nuclear and non nuclear forces, China is a country that could be involved in an immediate or potential contingency” (pp. 16–17).

19. 2010 NPR, p. 5.

20. 2010 NPR, p. iv.

21. 2010 NPR, p. 12.

22. 2010 NPR, p. 15.

23. For example, an excerpt from the Foreword in the 2001 NPR states: “U.S. forces must pose a credible deterrent to potential adversaries who have access to modern military technology, including NBC [Nuclear-Biological-Chemical] weapons and the means to deliver them over long distances.” Another excerpt from the report states: “Nuclear weapons could be employed against targets able to withstand non-nuclear attack, (for example, deep underground bunkers or bio-weapon facilities)” (pp. 12–13).

24. 2010 NPR, p.16.

25. 2010 NPR; 2001 NPR: “Nuclear weapons play a critical role in the defense capabilities of the United States, its allies and friends. They provide credible military options to deter a wide range of threats, including WMD and large-scale conventional military force.” See also, Arms Control Association, “U.S. ‘Negative Security Assurances’ at a Glance.”

26. Gareth Evans and Yoriko Kawaguchi, co-chairs, “Eliminating Nuclear Threats: A Practical Agenda for Global Policymakers,” International Commission on Nuclear Non-proliferation and Disarmament, Section 17, paras. 17.27–32, November 2009, <www.icnnd.org/reference/reports/ent/index.html>.

27. 2010 NPR, pp. 15, 28.

28. 2010 NPR, p. 33.

29. Scott D. Sagan, “Shared Responsibilities for Nuclear Disarmament,” Daedalus 138 (Fall 2009), pp. 157–68.

30. “President Bush Nominates Rob Portman as OMB Director and Susan Schwab for USTR,” White House Office of the Press Secretary, April 18, 2006, <georgewbush-whitehouse.archives.gov/news/releases/2006/04/20060418-1.html>. Quoted in Scott D. Sagan, “The Case for No First Use,” Survival 51 (June–July 2009), p. 174.

31. “Nuclear Threat Sullies U.S. Reputation: Leader,” Tehran Times, April 22, 2010, <www.tehrantimes.com/Index_view.asp?code=218012>.

32. Brahma Chellaney, “The NPT's Uncertain Future,” Japan Times, August 7, 2010, <search.japantimes.co.jp/cgi-bin/eo20100807bc.html>.

33. 2010 NPR, p. viii.

34. Lewis A. Dunn, Gregory Giles, Jeffrey Larsen, and Thomas Skypek, “Foreign Perspectives on the U.S. Nuclear Policy and Posture: Insights, Issues and Implications,” SAIC for the Defense Threat Reduction Agency, DTRA01-03-D-0017, December 12, 2006, <www.fas.org/irp/agency/dod/dtra/foreign-pers.pdf>.

35. Lewis A. Dunn, Gregory Giles, Jeffrey Larsen, and Thomas Skypek, “Foreign Perspectives on the U.S. Nuclear Policy and Posture: Insights, Issues and Implications,” SAIC for the Defense Threat Reduction Agency, DTRA01-03-D-0017, December 12, 2006, <www.fas.org/irp/agency/dod/dtra/foreign-pers.pdf>

36. Lewis A. Dunn, Gregory Giles, Jeffrey Larsen, and Thomas Skypek, “Foreign Perspectives on the U.S. Nuclear Policy and Posture: Insights, Issues and Implications,” SAIC for the Defense Threat Reduction Agency, DTRA01-03-D-0017, December 12, 2006, <www.fas.org/irp/agency/dod/dtra/foreign-pers.pdf> pp. 3–8.

37. Lewis A. Dunn, Gregory Giles, Jeffrey Larsen, and Thomas Skypek, “Foreign Perspectives on the U.S. Nuclear Policy and Posture: Insights, Issues and Implications,” SAIC for the Defense Threat Reduction Agency, DTRA01-03-D-0017, December 12, 2006, <www.fas.org/irp/agency/dod/dtra/foreign-pers.pdf> p. 3.

38. On material factors in foreign policy, see Kenneth N. Waltz, “Structural Realism after the Cold War,” International Security 25 (Summer 2000), pp. 5–41. See also, Michael Mastanduno, David A. Lake, and G. John Ikenberry, “Toward a Realist Theory of State Action,” International Studies Quarterly 33 (December 1989), pp. 457–74. On internal and external balancing, see James D. Morrow, “Arms Versus Allies: Trade-offs in the Search for Security,” International Organization 47 (1993), pp. 207–33.

39. 2010 NPR, p. 29.

40. The concept of “audience costs” has been mostly developed in the context of credibility of military threats by democracies. Democracies, it is argued, make more credible threats because they face greater costs for backing down, as publics electorally punish leaders for such backtracking. While the NPR is not a threat in the same sense, we can imagine that publics would be also likely to punish the president for reneging on a policy that outlines security commitments. For more on audience costs, see James D. Fearon, “Domestic Political Audiences and Escalation of International Disputes,” American Political Science Review 88 (September 1994), pp. 577–92; and Michael Tomz, “Domestic Audience Costs in International Relations: An Experimental Approach,” International Organization 61 (2007), pp. 821–40.

41. Sagan, “The Case for No First Use.”

42. On norms in international relations, see Martha Finnemore and Kathryn Sikkink, “International Norm Dynamics and Political Change,” International Organization 52 (Autumn 1998), pp. 887–91.

43. On state roles and identity in international relations, see James Rosenau, “Roles and Role Scenarios in Foreign Policy,” in Stephen G. Walker, ed., Role Theory and Foreign Policy Analysis (Durham, NC: Duke University Press, 1987), pp. 57–61; K.J. Holsti, “National Role Conceptions in the Study of Foreign Policy,” International Studies Quarterly 14 (September 1970), pp. 233–309.

44. On evaluative or prescriptive norms, which have standards of “appropriateness,” see Finnemore and Sikkink, “International Norm Dynamics and Political Change,” pp. 891–92.

45. “Draft Report of the National Security Advisory Board on Indian Nuclear Doctrine,” August 17, 1999, available through Pugwash, <www.pugwash.org/reports/nw/nw7a.htm>.

46. Sagan, “The Case for No First Use,” p. 176.

47. For details, see Scott D. Sagan, “The Evolution of Pakistani and Indian Nuclear Doctrine,” in Scott D. Sagan, ed., Inside Nuclear South Asia (Stanford, CA: Stanford University Press, 2009), pp. 219–63.

48. For more extensive propositions on how international norms develop, spread, and become adopted domestically, see Finnemore and Sikkink, “International Norm Dynamics and Political Change.”

49. 2010 NPR, p. 9.

50. 2010 NPR, p. 7.

51. 2010 NPR, p. 13.

52. Increased support for the US positions could also be a result of changed threat perceptions. However, articulation of that support in public forums suggests that the state seeks to demonstrate and promote its view, which would fit with a norms-diffusion explanation.

53. For more on the role of domestic actors in nuclear policy, see Etel Soligen, Nuclear Logics: Contrasting Paths in East Asia and the Middle East (Princeton, NJ: Princeton University Press, 2007).

54. Jennifer L. Erickson and Christopher Way, “Membership Has Its Privileges: Conventional Arms and Influence within the Nuclear Non-Proliferation Treaty,” in Robert Rauchhaus, Matthew Kroenig, and Erik Gartzke, eds., Causes and Consequences of Nuclear Proliferation (New York: Routledge, forthcoming 2011).