Bargaining with the Bomb: Militarized Nuclear Signals and Coercive Bargaining

• In Event: Shifting Nuclear Balance

Abstract

When and how coercive diplomacy using nuclear weapons succeed? Despite the importance of this question, past studies offer unsatisfactory answers. By exclusively focusing on the effect of nuclear weapons possession on dispute outcomes, existing research does not explore what actions states take using nuclear weapons during crises and how those actions contribute to bargaining leverage. Second, past studies fail to specify the conditions under which the benefits of using nuclear weapons could outweigh their costs (and vice versa), which affects the credibility of coercive nuclear threats. Last, previous studies rarely theorize the mechanisms through which intra-crisis behavior with nuclear weapons influences bargaining outcomes, both against nuclear-armed states and non-nuclear states.
To fill those gaps, this paper proposes a military signal theory of nuclear coercion. I focus on what I call a militarized nuclear signal—a military action a state takes with its nuclear-capable forces during coercive bargaining. Militarized nuclear signals include actions such as alerting nuclear forces, forward-deployment of nuclear-capable military units, and dispersion of nuclear delivery systems. These actions commonly increase the readiness of the mobilized nuclear forces or make them more proximate to the disputed territory (or the adversary’s territory).
I argue that sending a militarized nuclear signal increases the likelihood that a coercer achieves its aims, but its effects are not uniform across cases. Specifically, nuclear signals interact with three aspects of the bargaining environment: the target’s nuclear possession, and the balance of conventional and nuclear forces. I argue that militarized nuclear signals are effective only under certain circumstances, such as a severe nuclear disparity or when a non-nuclear target possesses superior conventional military power. These conditions make the benefits of using nuclear weapons greater than its costs. Under these conditions, therefore, militarized nuclear signals contribute to compelling the target to concede by increasing the target’s costs of resistance and perceived risk of inadvertent nuclear escalation.
To test this argument, I develop an original dataset on militarized nuclear signals during international crises using primary historical documents and secondary sources. The dataset covers all nuclear-armed states’ military signals with nuclear forces in all interstate crises from 1945 to 2002. Unlike other data on nuclear proliferation, which simply code nuclear weapons possession, this new dataset directly codes a wide array of intra-crisis behavior states took with their nuclear-capable forces during crises. My analysis covers all crises between non-nuclear states, nuclear-armed states and non-nuclear states, and nuclear-armed states. By using a comprehensive dataset, my statistical analysis provides more generalizable findings than previous research, which tend to focus on either well-known Cold War superpower crises or crises between India and Pakistan.
Using these new data, I investigate the relationship between militarized nuclear signals and interstate crisis outcomes. I find strong and robust support the hypothesis that militarized nuclear signals increase the probability of achieving crisis aims when the non-nuclear target possesses superior conventional military power. However, militarized nuclear signals play no role in shaping the outcomes of nuclear crises. I conclude with a brief discussion of the theoretical and policy implications of my findings on nuclear coercion, nuclear proliferation, and interstate coercion.

Author

• Kyungwon Suh, Syracuse University