Japan’s Peace Diplomacy on the Vietnam War and the 1968–1969 Shift in the United States’ Asia Policy

This article investigates the impact of the changing international environment in Asia at the turn of the 1960s on Japanese diplomacy regarding the Vietnam war and Southeast Asia. In 1968–1969, the United States announced important changes in its policy on the Vietnam problem and Asia, particularly the reduction of its military involvement in the region. Taking advantage of a US policy shift, China and the Soviet Union sought to expand their influence in Southeast Asia. Drawing on declassified diplomatic documents, this article shows that the government of Japanese Prime Minister Satō Eisaku, balancing domestic pressures and the need to preserve relations with Washington, adjusted its diplomacy in response to changes in the regional environment. While continuing efforts towards peace in Vietnam, Japan began work to shape a post-Vietnam Southeast Asian order based on peaceful coexistence between communist and non-communist countries. This was Japan’s strategy for countering the expected increase in Beijing and Moscow’s regional influence. Japan gradually acted to engage North Vietnam, a key actor to realize regional peaceful coexistence and a war settlement – which would in turn facilitate the realization of the reversion of Okinawa to Japan. This approach would be formalized in the 1977 Fukuda Doctrine.