This project examines the impact of nuclear proliferation on regime and leader survival, proposing two mechanisms for this interaction. First, a bomb program can generate internal legitimacy by rallying support among relevant domestic audiences. Such initiatives are particularly valuable following contentious successions, providing new leaders with a means of consolidating their rule. Second, successful proliferation attempts can boost external security by incentivizing the international community to prevent regime collapse, either deterring foreign intervention or entrapping great powers into providing costly support to tentative allies. In the former, fears of nuclear inheritance, lost fissile materials, or last-ditch nuclear use can persuade major powers to back the continued survival of nuclear-capable states. In the latter, the shadow of nuclear escalation can motivate patrons to provide costly diplomatic or material support to client states. I rely on a mixed-methods research design to test these arguments. Survival analysis, Bayesian modeling, and a battery of robustness tests establish a baseline domestic hazard rate relative to nuclear activity. Next, two in-depth case studies trace the processes linking proliferation and political survival in Israel and South Africa, showing how weapons programs generate domestic support, deter external aggression, and entrap great power assistance. These benefits hold for as long as nuclear capabilities are maintained, prolonging the lives of states that would have otherwise faced insurmountable existential challenges. The analysis concludes with fifteen vignettes that highlight the generalizability and limitations of my theoretical framework.