Nuclear Weapons and Coercive Diplomacy Published Aug. 22, 2017 Nuclear Weapons and Coercive Diplomacy by Todd S. Sechser and Matthew Fuhrmann. Cambridge University Press, 2017, 333 pp. In 2016, then-presidential candidate Donald Trump appeared to endorse the proliferation of nuclear weapons, saying, “wouldn’t you rather, in a certain sense, have Japan have nuclear weapons when North Korea has nuclear weapons?”1 In doing so he endorsed the common assumption that North Korean possessing nuclear weapons would provide them such a coercive advantage that Japan (and South Korea) would have no choice but to similarly acquire nuclear weapons. This concern about nuclear coercion was specifically invoked in the 2010 Nuclear Posture Review that stated, “Their provocative behavior has increased instability in their regions and could generate pressures in neighboring countries for considering nuclear deterrent options of their own.”2 Todd S. Sechser and Matthew Fuhrmann dispute that nuclear weapons provide a coercive advantage and, looking at the historical cases, argue that in fact nuclear weapons do not provide any additional coercive advantage to the possessor. Throughout Nuclear Weapons and Coercive Diplomacy, Sechser and Fuhrmann develop and test a theory they call “Nuclear Skepticism.” The key points of this theory are that nuclear weapons do not add to a state’s ability to coerce, nuclear coercive threats are not perceived as credible due to their disproportionate effects, and coercive threats from nuclear states are no more likely to succeed than threats from nonnuclear states. Sechser and Fuhrmann rely on Schelling’s classic definition of a split in coercive diplomacy between compellence (or threats intended to change the status quo) and deterrence (or threats intended to maintain the status quo), with the exception that they use “compellent threat” and coercion interchangeably.3 This differentiation between coercion and deterrence is very significant for their theory because they are not questioning the usefulness of nuclear weapons for deterrence (which has been extensively studied), but instead for compellent actions (which has been relatively neglected). Within their theory, they identify a number of problems with the use of nuclear weapons for coercion, the most significant of which is that, unlike deterrence, the stakes for compellence are not generally high enough to make a nuclear threat credible.4 Coercive threats, in their definition, generally resolve around relatively minor disputes where nuclear usage would be overkill given the stakes, the international costs (via sanctions or military response) are likely too high to be worth a relatively small gain, and signaling nuclear resolve remains difficult. While that may be the case now, they do point out that these international norms and repercussions may not always exist, and it is not hard to imagine a world where the military utility of nuclear weapons outweighs the cost of their usage.5 Examining the historical record quantitatively, Sechser and Fuhrman look at the effectiveness of compellent threats by nuclear and nonnuclear states.6 Through their analysis, they determine that nuclear states have no better success rate than nonnuclear states in issuing successful compellent threats or in territorial negotiations. While their quantitative analysis shows that nuclear states do not have a better success rate than nonnuclear states in coercive diplomacy, their first set of analyses does not directly measure the success rate of nuclear threats. To account for this, Sechser and Fuhrmann conducted a detailed analysis of the 19 cases of explicit nuclear threats throughout the nuclear era, ranging from nuclear alerts to overt nuclear threats. Again, they find success in only 10 of the 19 cases studied which, although higher than the success rate for general compellent threats, does not demonstrate much coercive advantage for nuclear weapons. Through their analysis, they additionally expose some broader definitional and signaling issues. In one particularly illustrative case of failed coercion, President Nixon deployed nuclear bombers to signal resolve against North Korea, but that signal that was totally missed by both the Soviet Union and North Korea. They also identify that of their 19 nuclear threat cases, a good number of them could be viewed as a deterrent success, vice a coercive action. The most significant of these cases was the Cuban Missile Crisis, commonly viewed as validating nuclear coercion but that could also be seen as a deterrent and bargaining success. One of the major critiques of their analysis is the definition of nuclear coercion. Throughout the 19 specific cases they analyzed, some are clearly nuclear while many of them contain borderline nuclear aspects or—in the case of Israel—the nuclear coercion of a third party. Additionally, the line between coercion/compellence and deterrence is quite vague and in most cases depends upon your point of view. Many of their cases included a nuclear dyadic relationship and inherently contained both compellent and deterrent aspects. Thus, it is not always clear whether nuclear coercion is ineffective or deterrence is just that much more effective. Even when one party did not have nuclear weapons, the great power politics of the Cold War (and associated extended deterrence) may have dwarfed any coercive benefits of nuclear weapons. Additionally, Sechser and Fuhrmann acknowledge that many leaders believe, at least at first, that they have gained some coercive benefits from nuclear weapons. While the case of Pakistan demonstrates nuclear powers may learn that nuclear weapons have limitations, that does not necessarily mean a young nuclear power will not initially act aggressively. The authors make a compelling case that nuclear coercion is no more effective than nonnuclear coercion, but that does not mean the transition period until new nuclear states learn their coercive limitations will not be dangerous. Thus, a note of caution is in order since just because none of the nuclear states to date have used nuclear weapons in a coercive attempt, that does not mean future ones will not. Despite those criticisms, this study opens a relatively neglected sector of nuclear scholarship and many promising avenues for future research. A variation of this study would be to compare the utility of nuclear coercion for conventionally weak and conventionally strong states, since for a conventionally weak state (for example, North Korea) nuclear weapons may not be redundant. Another relevant research topic would be to determine if the coercive utility of nuclear weapons changes as nuclear weapons change in size or precision, since nuclear overkill was one of their causal mechanisms. Even though nuclear coercion is not effective in the scenarios they analyzed, that does not mean it is without utility under changing conditions. In their timely analysis of nuclear coercion theory, Sechser and Fuhrmann convincingly argue that in today’s world nuclear states do not possess more coercive power than other nonnuclear states. The lessons they identify in their study of nuclear coercion have important implications, not just for nonproliferation efforts but also for deterrence theorists, particularly in the analysis of nuclear signaling challenges. Importantly, lest any nuclear critics try to use their work as evidence for disarmament, they point out that many of the challenges with coercion are not an issue for deterrence and “it would be a mistake to assume that nuclear weapons are irrelevant just because they do not have coercive effects.” Joe Petrucelli George Mason University Notes 1. Stefanie Conden, “Donald Trump: Japan, South Korea Might Need Nuclear Weapons,” CBS News, 29 March 2016, http://www.cbsnews.com/news/donald-trump-japan-south-korea-might-need-nuclear-weapons/. 2. Department of Defense, “2010 Nuclear Posture Review Report,” April 2010, https://www.defense.gov/Portals/1/features/defenseReviews/NPR/2010_Nuclear_Posture_Review_Report.pdf. 3. Thomas Schelling, Arms and Influence (New Haven, CT: Yale University Press, 1968), 36–59, 69. 4. Specifically, they argue that compellent threats are generally issued over relatively minor issues such as territorial disputes. Since it does not seem reasonable that China would kick off a nuclear war with the United States and Japan over the Senkakus, nuclear brinksmanship is not convincing to adversaries in these situations. 5. An important caveat is that this is only true today because in most coercive situations nuclear weapons are largely redundant to conventional forces and because the overkill caused by nuclear usage in a low-stakes coercive situation would undoubtedly invoke significant international backlash. 6. Specifically, they use two different data sets: Sechser’s Militarized Compellent Threat dataset, which contains some 200 cases of compellent threats, and Huth and Allee’s dataset for territorial negotiations between 1919 and 1995, which contains 1,528 rounds of negotiations.