The Institutional Origins of South Korea-U.S.-Japan “Military Cooperation” : The Making of the Agreement regarding the Status of the United Nations Forces in Japan (UN SOFA) and Its Historical Legacy

The Agreement regarding the Status of the United Nations Forces in Japan was intended to define the legal status in Japan of the armed forces of those states that had participated, or would later participate, in the Korean War as United Nations forces pursuant to the UN Security Council resolutions of June and July 1950, particularly non-U.S. contingents. This article argues that the military linkage among South Korea, the United States, and Japan, forged during the Korean War, was institutionalized and organizationally consolidated through the conclusion of the Agreement between 1952 and 1954 and through the establishment of the United Nations Command Rear in 1957, which was intended to preserve the agreement’s effectiveness after the relocation of the United Nations Command to Korea. Although this linkage had clear limitations, since neither South Korea nor Japan had voluntarily sought it, the security structure established in 1957 remains significant because the United States sought to employ it as a form of collective security arrangement in East Asia and because its basic framework has, in broad terms, endured through 2026.