Date of Award


Degree Type


Degree Name

Doctor of Philosophy (PhD)


Political Science


Daniel McDowell


coercion, international conflict, nuclear deterrece, nuclear operations, nuclear weapons

Subject Categories

International Relations | Political Science | Social and Behavioral Sciences


What is the effect of military operations of nuclear weapons, defined broadly as the management of nuclear weapons and the implementation of doctrinal concepts by which the military uses nuclear weapons in peacetime and combat, on international conflict outcomes? This dissertation explores how employment dimensions of military nuclear operations influence patterns of interstate military conflicts. The existing quantitative literature on nuclear weapons and international conflict mainly explores the impact of nuclear weapons possession on patterns of interstate conflict by using crude metrics of nuclear capabilities, such as binary measures of nuclear proliferation and a simple warhead count. These research practices are problematic, however, in two ways. First, they lead prior studies to understate the role of state action using nuclear-capable forces in influencing conflict behavior. Second, they also overlook how patterns of interstate conflicts are shaped by substantial variation in states’ military nuclear capabilities for various military nuclear missions, which are also directly related to the conceptual foundations of theories of nuclear deterrence. My dissertation investigates the impact of military nuclear operations on interstate conflict in two main ways: First, I explore the impact of intra-crisis military signals employing nuclear-capable forces on crisis outcomes. Second, I examine the effect of the variation in the ability of states’ nuclear arsenals to fulfill wartime nuclear missions on conflict outcomes.The first essay explores the coercive utility of nuclear weapons in crisis bargaining. It presents a new theory of nuclear coercion, which emphasizes the effect of military signals employing nuclear-capable forces in crises, rather than the mere possession of nuclear weapons, on crisis outcomes. The theory also argues that these militarized nuclear signals interact with military contexts of crises, such as targets’ nuclear possession and the balance of nuclear and conventional military power. Using a novel dataset on all episodes of militarized nuclear signals in crises, I find that militarized nuclear signals help states achieve crisis aims when facing conventionally superior non-nuclear opponents. However, nuclear signals do not create a measurable effect on crisis outcomes if the balance of conventional forces favors nuclear-armed coercers. In addition, the nuclear balance of power moderates the effect of nuclear signals in nuclear crises. In particular, militarized nuclear signals reduce the chance that coercers achieve crisis aims when the balance of nuclear forces favors nuclear-armed opponents. The second essay explores the effect of the nuclear balance of power on the initiation of foreign policy crises between nuclear-armed states. Scholars are divided as to whether possessing a superior nuclear arsenal produces deterrent advantages in peacetime, but the literature does not provide a quantitative evaluation of these competing claims. In addition, existing works often rely on crude indicators of military nuclear capabilities, such as a simple warhead count. I construct a novel dataset of strategic nuclear forces, which accounts for important technological features of nuclear capabilities, such as warhead delivery capacity, accuracy, and warhead yield. Using the dataset, my quantitative analysis finds that strategic nuclear superiority does not result in a reduced risk of nuclear crisis initiation. This result holds even when conditions generating a greater risk of nuclear escalation, such as targets’ adoption of escalatory nuclear posture or targets’ conventional military inferiority, exist. The third essay provides a new dataset on states’ minimum deterrent capabilities—the ability to impose nuclear punishment on opponents. Although this concept constitutes the central underlying mechanism for several quantitative studies on nuclear weapons, scholars mainly use datasets on nuclear proliferation for empirical analysis. By only measuring whether a state achieves a de facto nuclear weapon state status, however, these datasets do not consider a significant variation in states’ nuclear delivery capabilities and the geographic distance between opponents. To fix this mismatch between theories and measures, my dataset uses open-source information on all nuclear states’ delivery capabilities, nuclear weapons bases, and geographical distance between states to measure all nuclear states’ ability to strike a given opponent with nuclear weapons from 1945 to 2010. Empirical applications demonstrate that the robustness and the interpretation of several findings from prior studies depend on our choice of appropriate measures of nuclear capabilities given our theoretical interests.


Open Access