Explaining the Formulation of the San Francisco System: A Comparative and Eclectic Analysis of U.S. Bilateral Alliances in East Asia

Although the U.S. hub-and-spokes system was created during the Cold War to contain communism, it has remained resilient for over seven decades. This article examines the formulation of the San Francisco System (SFS) in East Asia, rather than its implementation or effectiveness. Existing scholarship often selects cases to fit specific theories, limiting explanatory power. As a result, the five main theories of alliance formation do not fully explain why alliances emerged in East Asia’s unique context. To address this gap, the article proposes analytical eclecticism instead of a single grand theory. It argues that alliance formation in asymmetric contexts is best understood as the interaction of multiple mechanisms rather than one dominant factor, offering a more comprehensive framework for analyzing the origins of the SFS and regional security architecture.