Proliferating Security? : explaining U.S. policy towards nuclear weapon aspirants

The proliferation of nuclear weapons has been a critical concern of the United States since World War II. While limiting the spread of nuclear weapons was a uniform goal of American administrations, in actual practice, there was significant variability in approaches to states as they approached the threshold of weaponization or crossed it. Against allied South Korea, America used the threat of military abandonment and technology denial to force the country to curtail its nuclear ambitions. In the case of a hostile China in the 1960s, military threats were the tool of choice. Policy variability cut across the ally/opponent divide, encompassing an ambivalent acceptance of non-aligned India’s nuclear capabilities by Ford in the 1970s and an acquiescence with China’s by Reagan in the 1980s. I argue that explanations based purely on the International Structure or Domestic Politics do not sufficiently explain these outcomes. I propose a causal mechanism that shapes the U.S. response to nuclear proliferation based on two independent variables, ‘Strategic Liability’ and ‘Commercial Value’. Strategic Liability is rooted in the International System, while Commercial Value is rooted in the domestic political economy of the U.S. Strategic liability is the Executive’s perception of risk from the nuclear program of a particular state, whereas Commercial value is the Executive’s estimation of the economic importance of that state. I show how these variables act on the American Executive, privileging its role in shaping the United States’ response to a state’s attempts to develop nuclear weapon capabilities. I posit four policy outcomes based on the combination of these independent variables, which take a high or low value. I test my argument by analyzing the U.S. response to the four major cases noted above, each corresponding to a unique combination of strategic liability and commercial value.