Adopting a liberal international institution entails not just the economic issues of efficiency and stability,but the diplomatic issues of alliance and multilateralism. Yet existing systemic theories of international institution are unable to analyze the process and outcome of adoption, because the theories do not have appropriate analytical insights into domestic negotiations between decision makers holding distinct policy positions over the issues. This article applies rational choice theory to an analysis of the trade liberalization efforts by the Ikeda Cabinet that involved both the economic and diplomatic issues. More specifically, the article content-analyzes parliamentary speeches by the Prime Minister, the Minister of Foreign Affairs, and the Director General of the Economic Planning Agency and captures the leader’s rhetorical manipulation of issue dimensions to pursue major trade liberalization under the emergent Cold War in East Asia through the exploitation of the cabinet’s unanimity rule. The analysis has an implication for the recent Abe Cabinet’s attempt at participating in the Transpacific Partnership (TPP) negotiations under changing security environments in the region.