Similar states, disparate treatment: Explaining inconsistent enforcement in the international nonproliferation regime

What are the causes and consequences of inconsistent enforcement of international law norms? Why do states undertake enforcement actions in certain cases and not others? Can states that may be the targets of enforcement take actions to shield themselves, enabling continued noncompliance with impunity? Much international relations and international law scholarship laments the absence of adequate enforcement mechanisms in the international system and celebrates the few instances of coercive enforcement as a vindication of the credibility of international legal regimes. Through a careful examination of coercive enforcement in a particularly significant area of international law---the nuclear nonproliferation regime---this study argues that instances of enforcement may be equally damaging to the credibility of international legal norms when undertaken inconsistently.;International law specifies objective criteria of compliance to determine whether states should be subjected to coercion to secure adherence to legal requirements. Where states violate basic norms structuring the international system---whether with respect to the international security order or in other core areas---the expectation is that they will be subjected to coercion with a view to securing a return to compliance. Yet a cursory review of the status of different states in the international system reveals that similarly situated states are frequently treated disparately with respect to the degree of coercion to which they are subjected. Some human rights abusers enjoy full participation in international cooperative arrangements, while others are systematically excluded; some weapons proliferators are subject to enforcement while others are not. My dissertation sets out to examine why states that engage in similar violations of international law are treated disparately and the consequences of that disparate treatment for securing future compliance.;The core hypothesis examined in this project is that the inconsistent enforcement of international legal norms is a consequence of the privileging of short-term strategic objectives over the long-term costs of inconsistency to the durability and credibility of international regimes. This hypothesis is a statement of a time-inconsistency (and commitment) problem, whereby states that may be the principal beneficiaries of an international legal regime nonetheless behave in ways that undermine its durability as a result of conflicting short-term preferences that lead to exemptions from enforcement. Thus, while the most powerful states in the international system have a vested interest in the long-term durability of international security regimes, in any particular instance in which enforcement is under consideration, they may weight their immediate strategic preferences with respect to the shielding of allies or the punishment of adversaries over the interest in consistent enforcement to optimize compliance with the regime.;This time-inconsistency hypothesis is examined through comparative consideration of three detailed, qualitative studies of nuclear proliferation records, and attendant enforcement outcomes, in the cases of Iran, Pakistan and South Korea. Through in-depth primary and secondary research and interviews, I reconstruct the nonproliferation compliance records of these countries and the consequent enforcement decisions taken by powerful states in the international system, together with the International Atomic Energy Agency and the United Nations system more broadly. I find that the three states were similarly situated at critical junctures in the development of their nuclear programs, but evidence of their violations of the nonproliferation regime (broadly understood) were treated quite differently. I argue that the principal explanation for this inconsistency lies in short-term strategic preferences---unrelated to nonproliferation---of powerful states in the international system at the particular junctures during which evidence of possible proliferation activity emerged. In examining the causes and consequences of inconsistent enforcement, this study evaluates competing explanations drawn from the international relations and international law literatures, while advancing arguments in favor of greater and more consistent enforcement.