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The Cornerstone and the Linchpin: Reconstituting U.S.-ROK- Japan Trilateral Security Cooperation

Issues & Insights Vol. 22, SR9, pp. 1-12


This paper focuses on the ‘why,’ ‘how,’ and ‘what’ of trilateral security cooperation by answering three interrelated questions. First, are there significant enough external and internal conditions to compel U.S.-ROK-Japan trilateral security cooperation? Second, what factors contributed to prior success in sustaining U.S.-ROK-Japan trilateral security cooperation? Third, in what areas can U.S.-ROK-Japan trilateral security cooperation be most effective? By examining the external pressures and internal changes that will continue to push Japan and South Korea closer together than in the recent past, this paper argues ‘why’ trilateral security cooperation is feasible. To understand ‘how’ trilateral security cooperation can be successfully sustained, this paper identifies the advantages of organizing the U.S.-ROK-Japan trilateral as a form of flexible multilateralism based on overlapping frameworks of cooperation rather than a formally binding agreement. To promote trilateral security cooperation in a way that recognizes both obstacles and opportunities, this paper recommends a pathway toward reconstituting U.S.-ROK-Japan trilateral cooperation based on this principle of flexible multilateralism. Finally, this paper focuses on the ‘what’ of trilateral security cooperation by recommending two areas of focus that appeal to the shared national security interests of the United States, Japan, and South Korea: 1) trilateral contingency planning for a Taiwan conflict and 2) commitment to a principle of ‘collective economic defense’ to buttress against future instances of economic coercion.

About this Volume

Authors of this volume participated in the inaugural U.S.-Japan Next-Generation Leaders Initiative, sponsored by the U.S. Department of State, through the U.S. Embassy Tokyo. With backgrounds from academia, government, military and industry, the cohort brings rich insights on the past, present, and future of the U.S.-Japan bilateral security relations.

The statements made and views expressed are solely the responsibility of the authors and do not necessarily reflect the views of their respective organizations and affiliations. Pacific Forum’s publications do not necessarily reflect the positions of its staff, donors and sponsors.

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Jada Fraser is an M.A. Student in Asian Studies at Georgetown University’s School of Foreign Service. Previously, she was a Policy Research Fellow with the Edwin O. Reischauer Center for East Asian Studies at Johns Hopkins SAIS. Her research for the Center primarily focused on prevailing geopolitical trends in the U.S.-Japan-China strategic triangle. Prior to joining SAIS, Jada worked as a Research Assistant with the Japan Chair at the Center for Strategic and International Studies. She focused on issues in the U.S.-Japan Alliance and U.S. and allies’ Indo-Pacific strategy. Her work has been published on the CSIS website. Jada graduated with High Honors and Departmental Special Honors from the University of Texas at Austin where she completed her B.A. in International Relations and Global Studies and was awarded a certificate in Security Studies from the Clements Center for National Security. Her current research interests include U.S. alliance strategy in the Indo-Pacific, Japan-South Korea relations, and strategic competition with China.

Photo: Flags representing the United States, Japan and the Republic of Korea are displayed during a trilateral meeting in 2018. Source: State Department photo/ Public Domain