How do countries ensure their security when relying on extended deterrence commitments? To answer this question, this dissertation examines in three comparative case studies—West Germany (1945-1960), China (1949-1964), and Israel (1948-1967)—how client states behave under extended deterrence arrangements beyond simply accepting the assurances of patron protection. Whereas the established literature on nuclear deterrence has centered on patron states and largely conceived of their relationships with clients as a one-way street, this dissertation shifts the analytical focus to the client states and seeks to understand their varying strategic choices. It presents a novel theoretical framework that explains how external security threats interact with domestic political environments to produce different policy outcomes. West Germany pursued a hedging strategy that allowed it to extract concessions from the United States, while abiding by its non-proliferation commitments. More ambitious strategies were constrained by strong public opposition to crossing the nuclear threshold. China eventually sought nuclear independence from an extended deterrence arrangement with the Soviet Union, driven by evolving beliefs about nuclear weapons in the absence of strong domestic opposition and a reliance on nationalist coalitions. Israel, meanwhile, pursued a policy of nuclear opacity, enabled by weak domestic opposition but, unlike in China’s case, shaped by reliance on internationalist coalitions, including close ties with the United States, which dictated avoiding overt violation of non-proliferation commitments.
Stephan Pietzner is a PhD researcher in the SPS Department at the EUI, working on nuclear security issues.