This article analyzes the promise—and limits—of pro-democratic intervention in international law. It revisits Immanuel Kant's influential prescription for peace, developed in Perpetual Peace: A Philosophical Sketch (1795), which has served as the foundation for democratic peace theory. This article emphasizes the unintended consequences of pro-democratic intervention in the international system. It finds arguments for the promotion of democratic entitlements deserving, but evidence for the existence of a right to democratic governance in international law wanting. The analysis, which incorporates evidence from cases, and synthesizes insights from scholarship in international law and international relations, casts doubt on the morality of democracy in the pursuit of international peace and security. It demonstrates that international lawyers have insufficiently appreciated the fact that democracy, if not handled with care, can underwrite democratic war—rather than democratic peace. This article argues that if the international community, however defined, truly aspires to realize the Kantian imperative of perpetual peace, it must enshrine democratic rights in unfamiliar cultures with more circumspection. Otherwise democratic rights become democratic wrongs, and policies of perpetual peace become prescriptions for perpetual war.