Although international precommitment regimes offer a tool to escape the apparent contradiction between sovereignty and the international protection of democracy and human rights, they raise theoretical and practical questions. This article draws on multinational archival research to explore an overlooked historical episode and suggest new thinking regarding the logjams over sovereignty, incapacity of global decision making, and humanitarian imperialism. In 1945 and 1946, the American states engaged in a debate over the Larreta Doctrine, a Uruguayan proposal about the parallelism between democracy and human rights, and the regional rights and duties to safeguard these values. In the ensuing debate, the Uruguayan foreign minister elaborated a tripartite precommitment mechanism to create a web of national commitments to democratic governance and the domestic protection of human rights, to establish a regional insurance policy against failures to maintain those commitments, and to obligate the great power and neighboring states to precommit to working through the regional system instead of unilaterally. As a proposal that emerged from a weak state—and garnered support from states that faced internal and external threats to democracy and rights—the Larreta Doctrine offers insights on the central tension between state sovereignty and international commitments.