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date: 11 December 2019

Inducements in Interstate Relations

Summary and Keywords

What has the academic scholarship found to date on the role of inducements, external incentives, or punishments to change the behavior of states in the international system? To understand the role of inducements in international relations, it is imperative to explore the full package of options, often referred to as “carrots and sticks” that are available in foreign policy decision-making to best understand when and why certain inducements are successful and why some may be more so than others. There are two big debates of policy importance to note here: Can nuclear decision-making be influenced by external actors, such as the United States? And, second, which set of tools are most helpful to the state seeking to change the behavior of another: carrots, sticks, or some combination of both? Although both incentives and punishments are generally used to change behavior in interstate relations, there are unique policy levers in the nuclear arena that scholars have recently begun to explore. The literature on inducements directly impacts ongoing policy debates, which in turn ultimately highlights the need for more research on nuclear-specific inducements. This article offers the first in-depth, systematic analysis of these inducement options, starting with their general use and then focusing specifically on inducements in the nuclear proliferation arena.

Keywords: inducements, carrots and sticks, international relations, bargaining, nuclear proliferation, counter-proliferation

The term “carrots and sticks” has long been known to scholars, policymakers, and the general public. In fact, its origins date back to 1938, when Winston Churchill first used the metaphor to demonstrate a reward-punishment combination: “Thus by every device from the stick to the carrot, the emaciated Austrian donkey is made to pull the Nazi barrow up an ever-steepening hill” (Churchill, 2008). There are three things about this statement that are vital to understanding the trajectory of positive and negative inducements both in practice and in scholarship. First, though Churchill is credited with coining the metaphor, most scholars place a predominant importance on the United States’ use of and role in inducements. Second, somewhere along the way scholars across a variety of issue areas in international relations lost sight of the combination of reward and punishment and began focusing almost exclusive energy toward understanding the punishment side of the equation to motivate changes in behavior. At least in the American context, this move of scholarship represents a response to policymakers’ lack of interest in positive inducements, due in part to a moral distaste of being seen to “reward bad behavior.”

Finally, and critically, this has real-world implications for how inducements are seen by policymakers and how they are implemented in practice. In attempting to manage crises ranging from intrastate conflict and repression to nuclear weapons and terrorism, it is critical to better understand the important role that inducements, both negative and positive, can play in influencing interstate relations. This may suggest something of a chicken/egg dilemma at play here—though whether the preponderant focus on negative inducements began first within the academic or policy community is outside the scope of this article. However, the need to better understand when, and in what combination, inducements are most effective remains paramount.

For example, U.S. national security advisor John Bolton has recently made it very clear that he sees no utility in positive inducements, noting that he is “not much of a carrots man” (Bergen, 2018). In this view of carrots, Bolton is not only stripping the United States of half the reward-punishment combination, he is reinforcing a changing view of the United States in the international system. For instance, as the United States has backed out of the Joint Comprehensive Plan of Action, it has sent a costly signal to allies and other nuclear weapons states like North Korea and has the potential to incite a new wave of nuclear aspirants such as Saudi Arabia. This issue extends beyond the nuclear realm, affecting U.S. credibility in bilateral and multilateral interactions alike.

This article aims to shed light on the trajectory of scholarship on inducements, with the goal of providing the first in-depth synthesis of the full package of inducement options. It begins with a general overview of the use of inducements in foreign policy and then focuses specifically on inducements in the counter-proliferation arena. What becomes apparent, as the article focuses on nuclear-specific inducements, is that there is even more exclusive attention paid to sticks in this arena despite increasing evidence that a more expansive approach that includes carrots is likely to be more effective. The focus here is on two big debates: Can nuclear decision-making be influenced by external actors, such as the United States? And second, which set of tools—positive inducements, negative inducements, or both—is most effective for this strategy? As the extant literature on inducements is traced, the article highlights work on positive inducements, negative inducements, and those few studies that examine the entire spectrum of inducements. Along the way, this article points out innovations in methodology and introduces original qualitative data to reveal the importance of a more exhaustive approach highlighting positive policy levers. The article concludes with a general assessment about implications of stones left unturned in the academic scholarship and extant policy debates.

An Overview of Positive and Negative Inducements

Inducements are often defined as external instruments of statecraft extended to a target state with the goal of persuading leaders to change their behavior. This could be with the goal of ending nuclear weapons activity, ending human rights violations, or behaving more desirably in a trade relationship (Pape, 1997). It should be noted that the terminology for describing the phenomenon of extending rewards or punishments to try to change a targeted state’s behavior has become somewhat loose as its study has advanced. Inducements, at their most general, describe both positive and negative strategies—benefits and sanctions. Elsewhere, sanctions sometimes refer to carrots—as in “positive sanctions” (Baldwin, 1971). To avoid confusion, the use of “inducements” in this article generally refers to positive or negative options to change behavior and to specify types of inducements where appropriate. Positive inducements are “benefits or rewards extended to leaders, ruling coalitions, or broader constituencies in target states with the expectation that they will persuade recipients to [change their behavior]” (Solingen, 2007). Negative inducements are defined as “international instruments of statecraft that punish or deny benefits to leaders, ruling coalitions, or broader constituencies in a given state, in an effort to dissuade those targets from [undesirable behavior]” (Solingen, 2007).

Both positive and negative inducements can be focused on political, economic, or security areas. Positive political inducements offer diplomatic recognition to a state or entrance into the broader international system. Extending or reinstating diplomatic ties and offering a state the chance to join the international order are similar in nature and purpose. Diplomatic ties are offered directly and bilaterally, whereas the chance to join the international order is offered multilaterally. The (re)instation of diplomatic ties can be a powerful inducement, both symbolically and actually. Symbolically, it sends a signal to the rest of the international community that the extending state approves of, and accepts as sovereignly equal, the receiving state (Narang & Mehta, 2019). This symbolic gesture also has actual benefits such as the chance to trade with the extending state. Offering a recipient state the chance to join the international community similarly has the same benefits: recognition by the United Nations provides sovereign legitimacy to the state, and being recognized by the World Trade Organization gives the state the opportunity for free and open trade. Negative political inducements threaten the reputation of a state in the international order or threaten to withhold diplomatic recognition.

Economic aid is the most common form of positive economic inducement and, at its broadest, is given to help the stability of a recipient country. As defined by the United States Agency for International Development (USAID, 2017), “Economic assistance is foreign aid for programs with a development or humanitarian objective. Development aid programs foster sustainable, broad-based economic progress and sociopolitical stability in developing countries.” The assistance encompasses programs that are non-military in nature including agriculture, environmental crises, development assistance, and economic support more generally.

Economic sanctions are probably the most-oft used and studied form of negative inducements. Nincic (2011) has argued that this is in part due to the real-politik tradition in the field. Sanctions can be general or targeted, meaning they can be levied at a state where all citizens feel the ramifications of the sanctions or they can be targeted to specific populations that may be more crucial to a leader’s ability to stay in power, as when the United States and the European Union imposed sanctions on Russian oligarchs in response to the country’s annexation of Crimea. Broadly defined, sanctions are the withdrawal of customary trade and financial relations with the specific intention of changing behavior. They have been viewed as a middle ground between diplomacy and military intervention (Masters, 2017). Finally, sanctions can be bilateral or multilateral in nature. All of the major powers have utilized their ability to levy sanctions individually. However, they can also act collectively through the United Nations Security Council. For example, the UNSC has employed economic sanctions against states such as Somalia, Liberia, and Yugoslavia during their civil crises, as well as Bashar Al-Assad’s regime during Syria’s civil war more recently (Masters, 2017).

Positive security inducements take the form of general military aid or specific security assurances under an alliance treaty. Military aid is broad in definition, generally known as aid used to assist a state in its defense efforts. Operationally, this can take the form of credits given by a donor country to the recipient for purchasing weapons or other military equipment from the donor or in the form of military education and training. It can be given for a variety of reasons—to counter terrorism, to support or quell a rebellion, to provide stability to a poor country, or specifically to support nonproliferation efforts. A promise to militarily defend a country is different and more specific. Military alliances are “written agreements, signed by official representatives of at least two independent states, that include promises to aid a partner in the event of military conflict, to remain neutral in the event of conflict, to refrain from military conflict with one another, or to consult/cooperate in the event of international crises that create a potential for military conflict” (Leeds, Ritter, Mitchell, & Long, 2002, p. 238). A specific type of positive security assurance will be discussed in greater detail in the next section, “Defining Counter-Proliferation,” that of the nuclear security umbrella, as it is unique to counter-proliferation.

Negative security inducements take the form of preventive war efforts and include a broad category of options that are meant to remove the capabilities of a state, but not necessarily change the behavior of it. Consider here Israel’s use of preemptive strikes, as part of a broader preventive war strategy, against the Egyptian and other Arab air forces in June 1967. This successful strategy likely contributed to Israel’s victory in the Six Day War (Strauss, 2017).

Preventive war plays a pivotal role in the nuclear context. The threat to engage in preventive war is issued as a means to change behavior, while the actual engagement in such efforts strips a state of certain capabilities. This is an important point that has been missed in much of the literature on inducements but that Mehta (2019) has described as a “game-ending move” and Cone (2019) has pointed out the distinction between the use of and the threat of these inducements. This point is expanded on in the following sections when the discussion is narrowed to inducements specifically used in counter-proliferation.

Defining Counter-Proliferation

Before explaining why states that begin nuclear weapons programs choose to renounce their nuclear ambitions, it is important to first understand the proliferation process. Unfortunately, the definition of nuclear weapons programs has been subject to wide variation in interpretation, but has resulted in two key points in the nuclear weapons development process: the opportunity/capability point and the willingness/decision point (Hymans, 2006; Jo & Gartzke, 2007; Meyer, 1984; Montgomery & Sagan, 2009; Singh & Way, 2004).1 Thus, a nuclear weapons program is defined as a motivated effort to acquire a nuclear explosive device and access to the necessary technical capabilities for building such a device.

Over the past 60 years (essentially since the earliest nuclear weapons acquisition), counter-proliferation or the conditions under which states stop their nuclear pursuit, has taken on a myriad of forms. Norway, for example, is not widely remembered as one of the world’s foremost nuclear entrepreneurs but it was one of the first states to acquire a nuclear reactor (Forland, 1997). After years of experimental research that included the difficult-to-attain capability to manufacture the fissile material necessary for a bomb (in this case, the separation of plutonium) at the start of the first wave of global nuclear proliferation in the 1950s, Norway ultimately opted to end its nuclear weapons program in the late 1960s. Contrastingly, a state like South Africa quietly pursued nuclear proliferation in the 1980s, even successfully completing production of six operational weapons and acquiring suitable delivery vehicles before ultimately agreeing to dismantle its weapons in adherence with International Atomic Energy Agency (IAEA) regulations (Mehta, 2019; Pabian, 1995).

Not surprisingly, the question of what constitutes counter-proliferation is similarly complex. To mirror initial proliferation decisions, a definition of counter-proliferation must also incorporate elements of action (e.g., dismantlement of existing facilities) and intention (i.e., adherence and compliance with the international non-proliferation regime). Similarly, nuclear reversal must be distinguished from a nuclear freeze, ambiguity in nuclear posture, or hedging (Abraham, 2010; Levite, 2003).2 This definition allows for the option that despite intentions of the international community and the proliferator, and the institutional mechanisms in place to ensure counter-proliferation, a proliferator may at some point in the future restart its program. This flexibility is allowed because it is most reflective of reality. As interstate relations evolve over time, states (such as Japan or South Korea) that seem unlikely to want to pursue nuclear weapons may opt to do so, even after receiving incentives from the international community to discourage regional proliferation behavior.

This definition also provides a crucial theoretical and empirical condition: a state is required to have begun active pursuit of a nuclear weapon, and subsequently abandoned or discontinued its proliferation activity, to be considered in this study. Past scholarship has often differentiated between different phases in the nuclear process: exploration activities, intended pursuit of the bomb, and the final assembly and acquisition of the nuclear device (Bleek, 2010; Mueller & Schmidt, 2008; Singh & Way, 2004). This has, however, led to discrepancies in how states are coded both in regard to their nuclear activity and underlying preference for nuclear acquisition.3

To attempt to resolve these discrepancies and establish a systematic baseline for investigation, characteristics of nuclear ambitions are aggregated into a broader construct that incorporates all three parts of the process—exploration, pursuit, and acquisition—to establish the universe of cases (Bleek, 2010; Mueller & Schmidt, 2008). To be classified as engaging in nuclear weapons activity, there must be evidence of technological behavior (such as indigenous production or receipt of nuclear technology or materials) and political behavior (discussions regarding a decision to pursue nuclear weapons program). To that end, counter-proliferation is defined as the observation and process of reversing a state’s decision to pursue nuclear weapons activity and a commitment to refrain from continued development, construction, or possession of nuclear weapons. The observation of counter-proliferation can then take on one of the following forms: permanent abandonment of active nuclear development, returning full weapons systems to another state or non-governmental organization, or the voluntary dismantlement of an operational nuclear arsenal. The process of reversing a state’s decision to pursue nuclear activity includes the strategies or tools used by the major power or sets of powers that desire the reversal of a nuclear ambitious state.

By incorporating all of the states that have ever pursued nuclear activity since 1945, a rather striking image begins to emerge. The expansion of this definition permits the examination of a much larger number of cases,4 resulting ultimately in much greater theoretical and empirical leverage for analysis (Bleek, 2010; Cone, 2019; Debs & Monteiro, 2017; Jo & Gartzke, 2007; Mehta, 2019; Mueller & Schmidt, 2008; Singh & Way, 2004; Spaniel, 2019). This empirical finding has several important takeaways. First, nuclear reversal—the outcome of successful counter-proliferation efforts—is not as rare as is often presumed in the literature, and in fact reflects the behavior of the strong majority of states who have undertaken some form of nuclear weapons activity. Second, a significant percentage of reversal occurred around the same time. The introduction of new states with nuclear weapons activities stagnated in the mid-1970s and ended essentially in the 1990s when the only new proliferators, Belarus, Kazakhstan, and Ukraine, had inherited their programs after the fall of the Soviet Union. On the other hand, successful counter-proliferation continued to grow in the late 1960s, stagnating and then ultimately skyrocketing after the mid-1980s. Third, the decision to stop these weapons programs cannot be attributed entirely to changes in decision-making at the domestic level—critically, dynamics at the international level can help us understand why states are willing to abandon their nuclear pursuits. These insights and the variation in the historical record lends itself to thorough theoretical and empirical investigation to help answer key questions about counter-proliferation in the international system—such as how best the international community can incentivize nuclear reversal.

Causes of Nuclear Proliferation and Reversal

The majority of scholarship on nuclear weapons activity has centered on two major questions: How do nuclear weapons affect the structure of the international system, and why do states pursue nuclear proliferation (Betts, 1990; Campbell, Einhorn, & Reiss, 2004; Sagan, 1997; Sagan & Waltz, 2003; Thayer, 1995)? These studies focus almost entirely on the initial decision to proliferate and the aftermath of these state decisions. Early theoretical literature and more recent empirical literature examines how nuclear weapons could be used as well as how they affect the balance of power among nuclear states and between nuclear and non-nuclear states (Betts, 1977; Huth & Russett, 1984, 1993; Jo & Gartzke, 2007; Gartzke & Kroenig, 2009; Kugler, 1984; Organski & Kugler, 1980; Russett, 1989).

The second strand of scholarship on nuclear weapons, and in part the foundation of this study, seeks to examine why states proliferate and the variance in proliferation paths, and to forecast which states are most likely to become new proliferators (Bell & Miller, 2015; Debs & Monteiro, 2017; Fuhrmann, 2009, 2012; Hymans, 2006; Jo & Gartzke, 2007; Montgomery & Sagan, 2009; Rublee, 2009; Sagan, 1997; Singh & Way, 2004; Solingen, 1994, 1998; Way & Weeks, 2014). These scholars argue that states pursue nuclear weapons for various reasons, including the acquisition of power to increase internal security, for organizational or bureaucratic interests, or for enhanced prestige in the international community (Sagan, 1997). Recent empirical studies have attempted to distill some of these initial theoretical findings by identifying the primary determinants of nuclear proliferation, isolating the mechanisms linking proliferation and conflict onset, and analyzing the effect of nuclear weapons on dispute initiation and/or bargaining outcomes and interstate relations more broadly (Gartzke & Kroenig, 2009).

Although the current state of the literature on counter-proliferation has thus far been able to account for many cases, it has had limited predictive power for some key aberrations found in the empirical record. This article identifies three limitations of this research to date and how this study’s approach may help mitigate some of these concerns.

First, the majority of studies on nuclear reversal or dismantlement are detailed single-state or regional case studies emphasizing the role of state-specific domestic politics that provide idiosyncratic analyses for why some countries opt to dismantle their nuclear weapons programs (Braut-Hegghammer, 2016; Hymans, 2006; Levite, 2003; Potter & Mukhatzhanova, 2010; Reiss, 1995; Rublee, 2009; Solingen, 2007). This research has provided important analyses of these states and produced significant theoretical implications for further analysis of counter-proliferation. For example, extant explanations for South Africa’s renunciation of nuclear weapons center on its unwillingness to transfer control of the nuclear arsenal to the African National Congress on the eve of democratization,5 and other analyses suggest that Argentina’s and Brazil’s decisions to stop their pursuit of nuclear weapons are due to the resolution of the security risk each posed to the other (Hymans, 2001; Reiss, 1995). Whether these explanations are generalizable beyond this specific case requires further investigation.

As a remedy, to the extent that this article can identify cross-national patterns to more effectively disincentivize future instances of proliferation, it deviates from the extant literature for three reasons. First, the literature seeks primarily to explain why states renounce nuclear weapons proliferation as a mirroring process to the initial pursuit of nuclear weapons. But this may or may not be the case. Although many states (Germany, South Korea, Taiwan, Iraq, and Libya) may have chosen to acquire nuclear weapons as a result of domestic political pressures, these states may in turn choose to voluntarily dismantle their weapons programs because they receive strategic incentives from the international community that are better than pursuit of nuclear weapons (e.g., by revising the status quo and/or increasing their share of the distribution of resources). This may have an indirect mitigating effect on internal pressures, but it may not necessarily be the precipitating cause of nuclear reversal. Indeed, these are not necessarily opposite processes, whereby, for example, the presence and subsequent absence of organizational biases explain state proliferation behavior. To the contrary, states may choose to proliferate for specific reasons and reverse their weapons programs for varied and unrelated reasons.

Second, the literature on counter-proliferation has centered on primarily realist-based, demand-driven explanations for state behavior that emphasize resolution of security concerns as a key motivation for nuclear reversal. Country-specific accounts for nuclear reversal, from Reiss’s 1995 study to more recent analyses, including Levite’s 2003 piece, describe nuclear renunciation as the result of an absence of external security threats. In this type of framework, states make the decision to acquire nuclear weapons to deter potential aggressors and secure their territories from attack without acquiring more territory or developing substantially larger conventional military capabilities (Foran & Spector, 1997; Levite, 2003; Mueller & Schmidt, 2008; Reiss, 1995; Sagan, 1997; Thayer, 1995; Waltz, 2003).6 In the event that this external threat is alleviated or a dispute is settled, proliferating states, such as South Korea, may decide to reverse their programs and stop development of a nuclear arsenal, retaining the capability to restart the program if another threat arises. However, these demand-driven models of proliferation fail to take into account supply-side or “opportunity” factors that are necessary for successful acquisition of nuclear weapons. States may desire acquisition of nuclear weapons but may lack the capabilities necessary for successful weaponization (Jo & Gartzke, 2007; Singh & Way, 2004). Other recent quantitative work on nuclear proliferation, for example, has emphasized the need to examine supply-side or opportunity variables in analyses of the determinants of nuclear proliferation. An external security threat may persist, but a proliferating state may ultimately decide to dismantle its program because the costs of continued development outweigh the benefits of counter-proliferation. This is especially true if the international community is able to provide an inducement, such as a security guarantee, or establish a military alliance that helps to alleviate an external threat that may have contributed to the initial decision to acquire nuclear weapons. Indeed, some have argued that although Japan and South Korea have both the opportunity (a high latent nuclear capacity) and willingness (an increasingly aggressive regional adversary, North Korea), they both remain non-nuclear states because of the promise of an extended nuclear deterrent (Mehta, 2019; Mehta & Whitlark, 2017; Narang & Mehta, 2019). Both sets of determinants are crucial for explaining the process of proliferation, but neither is sufficient for understanding why states may voluntarily reverse their weapons programs.

Third, the most recent scholarship on nuclear counter-proliferation has focused primarily on providing state- or regional-level explanations for why states decide to renounce nuclear weapons programs. Both Hymans and Solingen present domestic-level factors for counter-proliferation (Hymans, 2006; Mueller & Schmidt, 2008; Solingen, 2007). Hymans provides a leader-specific theory that argues that certain types of leaders are more likely to voluntarily stop developing nuclear weapons program, using the Australian case to illustrate his causal logic (Hymans, 2006; Mueller & Schmidt, 2008). Solingen, on the other hand, looks to regime-specific factors to outline her argument that the political-ideological orientation of the ruling coalition in the country may determine whether the state is likely to continue to pursue nuclear weapons (e.g., Argentina) or opt to voluntarily dismantle (e.g., Libya). She argues that domestic coalitions have varying preferences for nuclear policies, depending on how those coalitions view the effect of nuclear weapons on regime security (Solingen, 1994, 1998, 2007). On the other hand, Liberman’s analysis of South Africa, for example, stresses the need to incorporate both domestic and system-level explanations into a single-case study. He argues that the South African case was unique in that the decisions to arm and disarm were not mirroring. South Africa initiated its nuclear program in response to organizational and leader biases, whereas the improving security environment of the late 1980s and outward-looking politicians that sought the benefits of economic openness and interdependence drove its decision to give up its operational nuclear program (Liberman, 2001).

These studies highlight the limitations of many of the assumptions that underlie this initial scholarship. There are likely a variety of causal factors at work in proliferation and reversal decisions, and it is necessary to consider different levels of explanations. Taken together, these studies produce both important theoretical implications and other relevant factors that are necessary for case studies and a broader analysis. They also highlight the necessity of examining multiple explanatory factors at all relevant levels of analysis. In addition to identifying a more parsimonious explanation for states’ decisions to reverse their programs, one additional contribution of a larger, systemic analysis is to forecast the types of inducements, including positive inducements, that are most associated with persuading future proliferating states to reverse their nuclear programs. The following section, “The Use of Inducements in Counter-Proliferation,” addresses these gaps in the existing scholarship by introducing inducements in the context of nuclear counter-proliferation.

The Use of Inducements in Counter-Proliferation


Positive inducements come in two forms for counter-proliferation: (a) transferring resources such as technology, money, or knowledge to influence leaders to give up their weapons program (economic incentives) or (b) offering security assurances to remove a perceived threat, such as placing a state under the nuclear umbrella of a nuclear power, building confidence by creating or strengthening alliances, or offering diplomatic recognition (security incentives). Negative inducements come in both economic and security forms as well. Strategies for negative inducements include imposing economic sanctions (either unilaterally or multilaterally) on a state, threatening to withhold promised aid, or threatening or using military intervention (Baldwin, 1971; Bernauer & Ruloff, 1999; Cortright & Lopez, 1995, 2002; Davis, 2000; Drezner, 1999; Eyler, 2007; Haass & O’Sullivan, 2001; Miller, 2014; Miyagawa, 1992; Niblock, 2001; Solingen, 2007; Speier, Chow, & Starr, 2001).

There are two types of inducements that are unique to counter-proliferation: positive security assurances on the rewards side and threats or actual use of military force (including the targeting and killing of nuclear scientists and bombing of nuclear facilities) on the punishments side. A nuclear umbrella is a security arrangement under which the participating protégé states consent or acquiesce to the potential use of nuclear weapons in their defense by patron states while formally denouncing nuclear weapons of their own. Thus, the concept of extended nuclear deterrence can be understood as the umbrella’s intended effect (Huth, 1988; Murdock & Yeats, 2009; Reiter, 2014). There is a dual, concurrent goal of extended deterrence from the perspective of the patron state, to dissuade a would-be attacker from invading a protégé state while also persuading a protégé state that its commitments are credible.

This has important implications for proliferation and counter-proliferation decisions. The existing literature on proliferation offers a variety of logics and findings regarding the impact of formal alliances on nuclear weapons ambitions (Bleek & Lorber, 2013; Debs & Monteiro, 2017; Gerzhoy, 2015; Lanoszka, 2018; Miller, 2014). For example, neutrality and non-aggression pacts can satisfy security concerns by reducing the number of states that can be considered adversaries or opponents. Alternatively, by allowing a state to externally balance and rely on the military capabilities of other states if it is threatened, alliances may help incentivize states to reverse their own indigenous nuclear progress. Through either mechanism, nuclear umbrellas can effectively reduce the need for a nuclear program.

This, however, is incumbent on the credibility of the patron’s commitments. As the current geo-strategic environment continues to evolve, assumptions of credibility may be further strained or moot.7 For example, allies of superpower patrons may be likely to acquire nuclear weapons as bargaining chips in order to extract concessions such as economic or military aid from their patron state. It may especially be the case that states in an extended deterrent relationship may be likely to pursue nuclear weapons as a hedge against an uncertain future where the nuclear umbrella is weakened, removed, or lacks credibility. Efforts at counter-proliferation become increasingly difficult in an arena where patron states lack credibility in their promises to defend and protect allies, especially through the use of nuclear weapons. If this becomes the case, continued proliferation can be expected.


Though preventive war is not unique to nuclear proliferation, the bombing of nuclear facilities and the targeting and killing of nuclear scientists is. Fuhrmann and Kreps (2010) is probably the most comprehensive study of the use and threat of bombing as a means to counter nuclear proliferation. The authors conduct a large-N analysis of 12 states that threatened or actually attacked nine target states. There are, however, several studies that examine case studies of a singular bombing, most of which are focused on the Israeli bombing of Osiraq in 1981 (e.g., Feldman, 1982; Raas & Long, 2007; Ramberg, 1982; Reiter, 2005; Whitlark, 2017). Importantly, new work has begun to leverage more empirical variation by focusing on the decision by leaders to consider and/or use preventive military force to counter proliferation (Whitlark, 2017).

These studies generally suffer from potential selection biases or other empirical limitations. First, this type of policy tool has rarely actually been implemented (or at least that has been publicly acknowledged by the imposer of this cost). There are even fewer studies that focus on the targeting and killing of nuclear scientists for the same reason—so little is publicly available and vetted. Cone (2016) includes the small number of available instances of this inducement in a larger measure of negative inducements, and Tobey (2012) conducts an historical case study of the issue. Second, the consideration (or unwillingness to use this type of policy tool) has mostly been relegated to the policy community or crises du jour. Only recently has the academic scholarship been able to theoretically isolate when major powers, such as the United States, contemplate using military force and whether this consideration (and public threats) are themselves effective coercive tools (Whitlark, 2017).

Lastly, it is important to note that though this tool is often included as one of a spectrum of policy tools or inducements available to a state seeking to influence the nuclear reversal of another state, this article argues that this strategic choice may be mischaracterized as an “inducement” as its goal is not to change behavior, but rather to eliminate a capability altogether. This distinction, though seeming small in concept, is important from a theoretical and empirical perspective.

Advancements in the Field: Examining the Extant Literature in Depth

The most often studied and well-understood inducement for counter-proliferation is that of economic sanctions. The field has come a long way in understanding the effects of sanctions. Several studies seek to determine whether targeted or comprehensive sanctions are more effective (Bapat & Morgan, 2009); to provide general breadth over temporal and spatial domain (Hufbauer, Schott, Elliott, & Oegg, 2007; Morgan, Bapat, & Kobayashi, 2014); or to take a deeper dive into specific instances of the use of sanctions (Baldwin, 1971; Levy, 1999; Lopez & Cortwright, 2004) Still further studies question the effectiveness of sanctions (Pape, 1997), and as a response to this, Miller (2014) serves as one of the leading studies of the unexpected utility of economic sanctions. He argues that sanctions are more effective than scholars previously thought because they quell states from even seeking nuclear weapons programs in the first place. In response to the forgotten “rewards” side of inducements, especially in the context of counter-proliferation, several studies have emerged that either focus exclusively on the utility of positive inducements (Nincic, 2011; Reardon, 2010) or attempt to show their strength by including them alongside their negative counterparts (Cone, 2019).

Importantly, new research has begun to focus on how a combination of tools and approaches is important in understanding the processes that underlie counter-proliferation (Cone, 2019; Debs & Monteiro, 2017; Mehta, 2019; Spaniel, 2019). Debs and Monteiro, for example, zero in on the importance of underlying strategic considerations of opportunity and willingness—security concerns, relative power, and the reliability of allies (Debs & Monteiro, 2017). They argue that as critical and informative as these conditions are for understanding why states may want to acquire nuclear weapons, they are also useful in understanding why states may wish to forego or counter nuclear pursuit in the first place. States may wish not to pursue nuclear weapons for fear of being too vulnerable to external military intervention, that is, because of preventive war concerns. Specifically, Debs and Monteiro argue that “the efficacy of softer counter- and non-proliferation measures depends on the underlying credibility of threats to use military force against or in support of the potential proliferator” (Debs & Monteiro, 2017, pp. 38–39).

Relatedly, Cone takes as a starting point for her analysis that nuclear reversal is best understood by examining inducements as a package, as they are typically employed by policymakers (Cone, 2019). In doing so, scholars gain leverage not only on whether positive or negative inducements are more effective at countering proliferation, but also on what types of positive and negative inducements are most effective. Cone argues that when the full spectrum of inducements are examined, positive inducements are more effective at engendering nuclear reversal, as negative inducements may have unintended consequences for leaders who operate in a high-threat security environment. Economic sanctions are particularly ineffective in matters of counter-proliferation, and positive inducements offer leaders a “face-saving” measure that is particularly important in the nuclear context, as nuclear weapons hold a symbolic power not only in the international system but also for a leader’s domestic audience. From a domestic audience–centric framework, nuclear weapons often serve as a source of national pride. By accepting economic or military aid, or even diplomatic recognition with major powers, a leader gains something for his regime while still saving face for not capitulating to negative pressure from a major power.

Cone’s 2019 study makes an important contribution by taking the analysis a step further to distinguish what types of positive inducements are the most effective and under what conditions (Cone, 2019). Hawks and doves have long debated the best way to induce a reversal in a proliferator’s trajectory. Hawks advocate the use of sticks (sanctions, military action, or diplomatic isolation), whereas doves are the proponents of carrots (diplomatic recognition, economic and military aid, extended deterrence, and integration in the international community). However, previous research on inducements has remained agnostic to what types of positive (or negative) inducements are most effective, either lumping all types of positive inducements into one indicator, creating a count of the number of inducements received, or focusing on one specific type of positive inducement to explain the behavior of a target state without considering the other types. Arguing that a finer-grained conceptualization of inducements is necessary, Cone tests each of the arguments involved in these two distinct yet intersecting debates and finds that as positive inducements move from political to economic, to security in type, so does the likelihood of nuclear reversal.

Lastly, Mehta argues that nuclear reversal is most likely when states are threatened with sanctions and offered rewards that are tailored to compensate for a lost nuclear weapons deterrent in an effort to reduce the likelihood that the United States would use preventive military force against them (Mehta, 2019). This analysis reveals that sticks must be employed in tandem with carrots to motivate leaders to reverse nuclear course and agree to accept a deal to forego a nuclear deterrent. Indeed, this approach may provide a means to understanding the literature’s mixed findings on the utility of rewards and sanctions as merely opposite tools with no real impact. By employing them in tandem, these inducements have a powerful impact on domestic-level decision-making on counter-proliferation.

Importantly, Mehta’s study clarifies how inducements play a critical role in shifting how leaders view their nuclear weapons programs (Mehta, 2019). For leaders concerned about political fallout if they were to abandon their nuclear weapons programs, these inducements provide crucial political cover and a face-saving mechanism for satisfying their domestic constituencies. To compensate for the political costs of succumbing to exogenous pressures, leaders can highlight the political benefits of positive inducements and demonstrate the potential costs of negative inducements if they were to continue their nuclear efforts. In doing so, leaders can justify reversing nuclear progress, especially decades-long programs, without jeopardizing their own political futures.

Next Steps for Counter-Proliferation Scholarship

This article reviewed the state of the art on the role of inducements in interstate relations, specifically in curbing the spread of nuclear weapons in the international system. Although recent scholarship has begun to focus on this part of the proliferation equation, there is still more work to be done to fully understand what types of policy levers are most effective at altering nuclear decision-making. In light of current proliferation challenges (as well as other challenges to the international system), the study of inducements is likely to be increasingly salient in the coming years.

In light of this new scholarship and divergent approaches, as well as increasing ambiguity over the impact of a variety of potential foreign policy tools, new research must aim to improve understandings of the complex environment of counter-proliferation. One avenue will do so by exploring the multiple actors engaged in counter-proliferation policy areas simultaneously and by examining which tools utilized by which actors under which conditions can lead to successful counter-proliferation outcomes. This broader theoretical and empirical effort should lead to a more realistic assessment of the global counter-proliferation policy space and a more nuanced understanding of when policy interventions are likely to succeed. It will also chart a path forward for improving U.S. foreign policy by clarifying where productive cooperation can happen with a variety of like-minded international partners.

Understanding the conditions under which counter-proliferation is successful—or not—is an important part of broader U.S. foreign policy. Proliferation challenges are likely to persist in the future, with states developing or acquiring nuclear technology (horizontal proliferation) or advancing existing nuclear capabilities to pursue nuclear weapons (vertical proliferation). By understanding how states in the international system can interact to facilitate cooperation or spoil attempts to negotiate nuclear reversal, scholars and practitioners can better understand how the United States should operate in these interventions to successfully and efficiently counter the spread of nuclear technology. Given changing domestic political and financial constraints, as well as an evolving foreign policy that may be more limited in its attention to the nonproliferation regime, it is important to assess whether, and in what ways, other states may facilitate or hinder these global efforts. And in our own conversations with diplomats from the European Union and other emerging powers, it is becoming increasingly imperative that scholars, analysts, and policymakers work to better understand these complex dynamics to ensure that the nuclear club does not grow.

Finally, and importantly, advancements made in counter-proliferation literature can shed light on other empirical arenas in which countries use inducements to attempt to change behavior. For instance, the logic of counter-proliferation may help us better understand how inducements can influence other weapons programs, trade relationships, election fraud and other cyber-security issues, and territorial disputes. Given the increasing complexity of the current geo-strategic environment, these efforts are of the utmost importance.


Opinions, conclusions, and recommendations expressed or implied within this article are solely those of the author and do not necessarily represent the views of the Air University, the United States Air Force, the Department of Defense, or any other U.S. government agency. The authors thank Molly Berkemeier-Harvey, Rachel Whitlark, two anonymous reviewers, and the editors of the Oxford Research Encyclopedia of Politics for their thoughtful questions and valuable recommendations.

Further Reading

Baldwin, D. (1971). The power of positive sanctions. World Politics, 24(1), 19–38.Find this resource:

Cone, P. (2019). The power of the positive: Effectiveness of positive inducements in counterproliferation. Working Paper.Find this resource:

Debs, A., & Monteiro, N. (2017). Nuclear politics: The strategic causes of proliferation. Cambridge, U.K.: Cambridge University Press, Cambridge Studies in International Relations.Find this resource:

Drezner, D. (1999). The sanctions paradox: Economic statecraft and international relations. Cambridge, U.K.: Cambridge University Press.Find this resource:

Haass, R. N., & O’Sullivan, M. L. (Eds.). (2001). Honey and vinegar: Incentives, sanctions and foreign policy. Washington, DC: Brookings Institution Press.Find this resource:

Hufbauer, G., Schott, J., Elliott, K., & Oegg, B. (2007). Economic sanctions reconsidered. Washington, DC: Peterson Institute for International Economics, Clearance Center Press.Find this resource:

Mehta, R. N. (2019). The politics of nuclear reversal. Oxford, U.K.: Oxford University Press.Find this resource:

Miller, N. (2014). The secret success of nonproliferation sanctions. International Organization, 68(4), 913–944.Find this resource:

Miyagawa, M. (1992). Do economic sanctions work? London, U.K.: Palgrave Macmillan.Find this resource:

Morgan, T. C., Bapat, N., & Kobayashi, Y. (2014). The threat and imposition of sanctions: Updating the TIES dataset. Conflict Management and Peace Science, 3(5), 541–558.Find this resource:

Nincic, M. (2011). The logic of positive engagement. Ithaca, NY: Cornell University Press.Find this resource:

Pape, R. (1997). Why economic sanctions do not work. International Security, 22(2), 90–136.Find this resource:

Whitlark, R. (2017). Nuclear beliefs: A leader-focused theory of counter-proliferation. Security Studies, 26(4), 545–574.Find this resource:


Abraham, I. (2010). “Who’s next?” Nuclear ambivalence and the contradictions of non-proliferation policy. Economic and Political Weekly, 45(43), 48–56.Find this resource:

Baldwin, D. (1971). The power of positive sanctions. World Politics, 24(1), 19–38.Find this resource:

Bapat, N. A., & Morgan, T. C. (2009). Multilateral versus unilateral sanctions reconsidered: A test using new data. International Studies Quarterly, 54(4), 1075–1094.Find this resource:

Bell, M. S., & Miller, N. L. (2015). Questioning the effect of nuclear weapons on conflict. Journal of Conflict Resolution, 59(1), 74–92.Find this resource:

Bergen, P. (2018). New Trump adviser is “not much of a carrot man.” CNN, April 9.Find this resource:

Bernauer, T., & Ruloff, D. (1999). The politics of positive incentives in arms control. Columbia: University of South Carolina Press.Find this resource:

Betts, R. K. (1977). Nuclear blackmail and nuclear balance. Cambridge, MA: Harvard University Press.Find this resource:

Betts, R. K. (1990). A nuclear golden age? The balance before parity. In S. M. Lynn-Jones, S. E. Miller, & S. Van Evera (Eds.), Nuclear diplomacy and crisis management (pp. 39–68). Cambridge, MA: MIT Press.Find this resource:

Bleek, P. C. (2010). Why do states proliferate? Quantitative analysis of the exploration, pursuit, and acquisition of nuclear weapons. In W. C. Potter & G. Mukhatzhanova (Eds.), Forecasting nuclear proliferation in the 21st century: The role of theory (Vol. 1, pp. 159–192). Stanford, CA: Stanford University Press.Find this resource:

Bleek, P., & Lorber, E. (2013). Security guarantees and allied nuclear proliferation. Journal of Conflict Resolution, 58(3), 429–454.Find this resource:

Braut-Hegghammer, M. (2016). Unclear physics: Why Iraq and Libya failed to build nu clear weapons. Ithaca, NY: Cornell University Press.Find this resource:

Campbell, K. M., Einhorn, R. J., & Reiss, M. B. (2004). The nuclear tipping point: Why states reconsider their nuclear choices. Washington, DC: Brookings Institution Press.Find this resource:

Churchill, W. S. (2008). Churchill by himself: The definitive collection of quotations. Text copyright the Estate of Winston S. Churchill. U.K.: Ebury Press.Find this resource:

Cone, P. (2016). Leaders in search of the bomb: Institutional Incentives for Nuclear Decisions. (Doctoral dissertation). University of South Carolina, Columbia, SC.Find this resource:

Cone, P. (2019). The power of the positive: Effectiveness of positive inducements in counterproliferation. Working paper. OSF Registries, February 28.Find this resource:

Cortright, D., & Lopez, G. (1995). Economic sanctions: Panacea or peacebuilding in a post-Cold War world? Boulder, CO: Westview Press.Find this resource:

Cortright, D., & Lopez, G. (2002). Smart sanctions: Targeting economic statecraft. Lanham, MD: Rowman & Littlefield Publishers.Find this resource:

Davis, J. (2000). Threats and promises: The pursuit of international influence. Washington, DC: John Hopkins University Press.Find this resource:

Debs, A., & Monteiro, N. (2017). Nuclear politics: The strategic causes of proliferation. Cambridge, U.K.: Cambridge University Press, Cambridge Studies in International Relations.Find this resource:

Drezner, D. (1999). The sanctions paradox: Economic statecraft and international relations. Cambridge, U.K.: Cambridge University Press.Find this resource:

Eyler, R. (2007). Economic sanctions: International policy and political economy at work. New York, NY: Palgrave Macmillan.Find this resource:

Feldman, S. (1982). The bombing of Osiraq—revisited. International Security, 7(2), 114–142.Find this resource:

Foran, V. I., & Spector, L. S. (1997). The application of incentives to nuclear proliferation. In D. Cortright (Ed.), The price of peace: Incentives and international conflict prevention (pp. 21–53). Boulder, CO: Rowman & Littlefield.Find this resource:

Forland, A. (1997). Norway’s nuclear odyssey: From optimistic proponent to nonproliferator. Nonproliferation Review, 4(2).Find this resource:

Fuhrmann, M. (2009). Spreading temptation: Proliferation and peaceful nuclear cooperation agreements. International Security, 34(1), 7–41.Find this resource:

Fuhrmann, M. (2012). Atomic assistance: How “Atoms for Peace” programs cause nuclear insecurity. Ithaca, NY: Cornell University Press.Find this resource:

Fuhrmann, M., & Kreps, S. E. (2010). Targeting nuclear programs in war and peace: A quantitative empirical analysis, 1941–2000. Journal of Conflict Resolution, 54(6), 831–859.Find this resource:

Gartzke, E., & Kroenig, M. (2009). A strategic approach to nuclear proliferation. Journal of Conflict Resolution, 53(2), 151–328.Find this resource:

Gerzhoy, G. (2015). Alliance coercion and nuclear restraint: How the United States thwarted West Germany’s nuclear ambitions. International Security, 39(4), 91–129.Find this resource:

Haass, R. N., & O’Sullivan, M. L. (Eds.). (2001). Honey and vinegar: Incentives, sanctions and foreign policy. Washington, DC: Brookings Institution Press.Find this resource:

Hufbauer, G., Schott, J., Elliott, K., & Oegg, B. (2007). Economic sanctions reconsidered. Washington, DC: Peterson Institute for International Economics, Clearance Center Press.Find this resource:

Huth, P. K. (1988). Extended deterrence and the prevention of war. New Haven, CT: Yale University Press.Find this resource:

Huth, P. K., & Russett, B. (1984). What makes deterrence work? Cases from 1900 to 1980. World Politics, 36(4), 496–526.Find this resource:

Huth, P. K., & Russett, B. (1993). General deterrence between enduring rivals: Testing three competing models. American Political Science Review, 87(1), 61–73.Find this resource:

Hymans, J. (2001). Of gauchos and gringos: Why Argentina never wanted the bomb, and why the United States thought it did. Security Studies, 10(3), 153–185.Find this resource:

Hymans, J. (2006). The psychology of nuclear proliferation: Identity, emotions, and foreign policy. Cambridge, U.K.: Cambridge University Press.Find this resource:

Jo, D.-J., & Gartzke, E. (2007). Determinants of nuclear weapons proliferation: A quantitative model. Journal of Conflict Resolution, 51(1), 167–194.Find this resource:

Kugler, J. (1984). Terror without deterrence: Reassessing the role of nuclear weapons. Journal of Conflict Resolution, 28(3), 470–506.Find this resource:

Lanoszka, A. (2018). Atomic assurance: The Alliance politics of nuclear proliferation. Ithaca, NY: Cornell University Press.Find this resource:

Leeds, B. A., Ritter, J. M., Mitchell, S. M., & Long, A. G. (2002). Alliance treaty obligations and provisions, 1815–1944. International Interactions, 28(3), 237–260.Find this resource:

Levite, A. (2003). Never say never again: Nuclear reversal revisited. International Security, 27(3), 59–88.Find this resource:

Levy, P. I. (1999). Sanctions on South Africa: What did they do? American Economic Review, 89(2), 415–420.Find this resource:

Liberman, P. (2001). The rise and fall of the South African bomb. International Security, 26(2), 45–86.Find this resource:

Lopez, G., & Cortright, D. (2004). Containing Iraq: Sanctions worked. Foreign Affairs, 4, 90–103.Find this resource:

Masters, J. (2017). What are economic sanctions? Council on Foreign Relations, August 7.Find this resource:

Mehta, R. N. (2019). The politics of nuclear reversal. Oxford, U.K.: Oxford University Press.Find this resource:

Mehta, R., & Whitlark, R. (2017). Assessing the benefits and burdens of nuclear latency. International Studies Quarterly, 61(3), 517–528.Find this resource:

Meyer, S. M. (1984). The dynamics of nuclear proliferation. Chicago, IL: University of Chicago Press.Find this resource:

Miller, N. (2014). The secret success of nonproliferation sanctions. International Organization, 68(4), 913–944.Find this resource:

Miyagawa, M. (1992). Do economic sanctions work? London, U.K.: Palgrave Macmillan.Find this resource:

Montgomery, A. H., & Sagan, S. D. (2009). The perils of predicting proliferation. Journal of Conflict Resolution, 53(2), 302–328.Find this resource:

Morgan, T. C., Bapat, N., Kobayashi, Y. (2014). The threat and imposition of sanctions: Updating the TIES dataset. Conflict Management and Peace Science, 3(5), 541–558.Find this resource:

Mueller, H., & Schmidt, A. (2008). The little known story of de-proliferation: Why states give up nuclear weapon activities. ISA Convention Paper. San Francisco, CA, March 26–29.Find this resource:

Murdock, C., & Yeats, J. (2009). Exploring the nuclear posture implications of extended deterrence and assurance. Workshop Proceedings and Key Takeaways. Washington, DC: Center for Strategic and International Studies.Find this resource:

Narang, N., & Mehta, R. N. (2019). The unforeseen consequences of extended deterrence: Moral hazard in a nuclear protégé. Journal of Conflict Resolution, 63(1), 218–250.Find this resource:

Niblock, T. (2001). Pariah states and sanctions in the Middle East: Iraq, Libya, Sudan. Boulder, CO: Lynn Rienner.Find this resource:

Nincic, M. (2011). The logic of positive engagement. Ithaca, NY: Cornell University Press.Find this resource:

Organski, A. F. K., & Kugler, J. (1980). The war ledger. Chicago, IL: University of Chicago Press.Find this resource:

Pabian, F. V. (1995). South Africa’s nuclear weapon program: Lessons for U.S. non proliferation policy. Nonproliferation Review, 3(1), 1–19.Find this resource:

Pape, R. (1997). Why economic sanctions do not work. International Security, 22(2), 90–136.Find this resource:

Potter, W., & Mukhatzhanova, G. (2010). Forecasting nuclear proliferation in the 21st century. Stanford, CA: Stanford University Press.Find this resource:

Raas, W., & Long, A. (2007). Osirak redux? Assessing Israeli capabilities to destroy Iranian nuclear facilities. International Security, 31(4), 7–33.Find this resource:

Ramberg, B. (1982). Attacks on nuclear reactors: The implications of Israel’s strike on Osiraq. Political Science Quarterly, 97(4), 653–669.Find this resource:

Reardon, R. (2010). Nuclear bargaining: Using carrots and sticks in nuclear counter-proliferation. (Doctoral thesis). Massachusetts Institute of Technology, Cambridge, MA.Find this resource:

Reiss, M. (1995). Bridled ambition: Why countries constrain their nuclear capabilities. Washington, DC: Woodrow Wilson Center Press.Find this resource:

Reiter, D. (2005). Preventive attacks against nuclear programs and the success at Osiraq. Nonproliferation Review, 12(2), 355–371.Find this resource:

Reiter, D. (2014). Security commitments and nuclear proliferation. Foreign Policy Analysis, 10(1), 61–80.Find this resource:

Rublee, M. R. (2009). Nonproliferation norms: Why states choose nuclear restraint. Athens: University of Georgia Press.Find this resource:

Russett, B. (1989). The real decline in nuclear hegemony. In E.-O. Czempiel & J. N. Rosenau (Eds.), Global changes and territorial challenges: Approaches to world politics for the 1990s (pp. 177–193). Lexington, MA: Lexington Books.Find this resource:

Sagan, S. D. (1997). Why do states build nuclear weapons? Three models in search of a bomb. International Security, 2(3), 54–86.Find this resource:

Singh, S., & Way, C. (2004). The correlates of nuclear proliferation. Journal of Conflict Resolution, 48(6), 859–885.Find this resource:

Solingen, E. (1994). The political economy of nuclear restraint. International Security, 19(2), 126–169.Find this resource:

Solingen, E. (1998). Regional orders at century’s dawn: Global and domestic influences on grand strategy. Princeton, NJ: Princeton University Press.Find this resource:

Solingen, E. (2007). Nuclear logics: Contrasting paths in East Asia and the Middle East. Princeton, NJ: Princeton University Press.Find this resource:

Spaniel, W. (2019). Bargaining over the bomb: The successes and failures of nuclear negotiations. Cambridge, U.K.: Cambridge University Press.Find this resource:

Speier, R., Chow, B., & Starr, S. R. (2001). Nonproliferation sanctions. Santa Monica, CA: RAND Corp.Find this resource:

Strauss, B. (2017). Preemptive strikes and preventive wars: A historian’s perspective. Strategika, Issue 44. Hoover Institution.Find this resource:

Thayer, B. (1995). Nuclear weapons as a Faustian bargain. Security Studies, 5(1), 149–163.Find this resource:

Tobey, W. (2012). Nuclear scientists as assassination targets. Bulletin of the Atomic Scientists, 68(1), 61–69.Find this resource:

Waltz, K. (2003). More may be better. In S. D. Sagan & K. N. Waltz (Eds.), The spread of nuclear weapons: A debate renewed (2nd ed., pp. 3–45). New York, NY: Norton.Find this resource:

Way, C., & Weeks, J. L. (2014). Making it personal: Regime type and nuclear proliferation. American Journal of Political Science, 58, 705–719.Find this resource:

Whitlark, R. (2017). Nuclear beliefs: A leader-focused theory of counter-proliferation. Security Studies, 26(4), 545–574.Find this resource:

U.S. Agency for International Development. (2017). U.S. overseas loans and grants: Obligations and loan authorizations, July 1, 1945–September 30, 2017. CONG-R-0105. Washington, DC: USAID.Find this resource:


(1.) The difficulty arises when using one point or the other as the defining characteristic of starting a nuclear weapons program. By placing either intent or capability as senior to the other, one can introduce biases that result in over- or under-estimation of nuclear weapons programs. To mitigate this potential bias, this article adopts the current standard in the literature and incorporates both simultaneously as necessary conditions.

(2.) For the purposes of congruence with other analyses in the field, this article then adopts a definition suggested by Ariel Levite—“the phenomenon in which states embark on a path leading to nuclear weapons acquisition but subsequently reverse course, though not necessarily abandoning altogether their nuclear ambitions . . . including a governmental decision to slow or stop altogether an officially sanctioned nuclear weapons program”—as a basis for selection into the population of interest (Levite, 2003; Mueller & Schmidt, 2008).

(3.) For example, Singh and Way (2004) exclude West Germany from their analysis, whereas others argue that West Germany explored the bomb option but took only limited actions toward acquisition as a result of U.S.-imposed restrictions on the possession of nuclear arms, not a weaker preference for a nuclear deterrent. Similarly, Singh and Way (2004) classify South Korea’s shift from nuclear “exploration” to renunciation as a diminished preference for nuclear weapons, whereas other evidence suggests that South Korea’s change in policy, from “pursuit” to “reversal,” was instead the result of U.S. pressure to renounce nuclear weapons.

(4.) The total universe of cases, 31 or 34, depends on the inclusion of three former Soviet satellite states that opted to relinquish their inherited arsenals upon independence. Although some argue that these cases are not true instances of nuclear reversal, as these states inherited nuclear weapons but did not choose to acquire them in the first place, there are reasons to include these states. Though the former Soviet republics did not make the choice independently to begin nuclear weapons programs, their leaders each made the decision to relinquish the weapons that were left on their sovereign territory once the Soviet Union broke apart. The factors that played into decision-making for dismantling and reversing their nuclear arsenals are important to consider. Interestingly, analyses with and without their inclusion generally yield similar results.

(5.) More recent scholarship provides an alternative take on South Africa’s nuclear renunciation.

(6.) T.V. Paul is among the first to highlight the logical inconsistencies in the neorealist argument about proliferation by noting the negative security externalities of proliferation: developing weapons program could trigger a reaction that may actually make the proliferating state less secure. Anticipating this would make a threatened state less likely to want to pursue nuclear weapons.

(7.) This point was reaffirmed in several off-the-record interviews with European and Latin American policymakers.