2002 年 2002 巻 130 号 p. 92-108,L10
During this period, Prime Minister Eisaku Sato faced three important challenges: the U. S. escalation of the Vietnam War, the extension of the U. S. -Japan security treaty in 1970, and the reversion of Okinawa. These three issues were inter-related, having an impact on each other. Sato had several reasons to support the U. S. Vietnam policy: the war made it difficult for Japan to play a larger non-military role in Asia; it made the reversion of Okinawa extremely difficult with the U. S. bases playing an essential role in the U. S. war efforts. Moreover, with the war continuing, Sato feared, the opposition would take advantage of the mounting anti-war sentiments to repudiate the security treaty in 1970 by linking B-52s' bombing missions from Okinawa and the Vietnam War with the security treaty. The Johnson administration, on the other hand, also wanted Japan to play a larger role in Asia for its own reasons: their need to reduce U. S. over-commitments, especially in view of the deteriorating balance of payments; their desire for Japan's expanding role to accommodate the rising nationalist sentiments among Japanese; above all, the administration's desire for Japan's public support for the U. S. war efforts as well as her increased aid to Southeast Asian countries including South Vietnam.
The Japanese government's effort at mediation was part and parcel of his over-all efforts to meet such U. S. expectations. Sato not only supported the U. S. Vietnam policy but also responded positively to expanding Japan's role in Asia as had been urged by Washington. Sato hoped that such cooperative efforts would make a good impression on President Johnson and his advisors, thus creating a favorable atmosphere for negotiations for the Okinawa reversion. Sato's tactics worked but at the cost of eroding Japan's role as a mediator. His closer identification with Washington and Saigon beginning in the summer of 1967 further eroded Japan's role as a mediator in the Vietnam War. The Okinawa reversion was achieved at the expense of the inhabitants on Okinawa. Given Sato's own convictions, he found no difficulty accepting Washington's rationale that the bases on Okinawa contributed not only to regional security in Asia but also to that of Japan. This logic, however, required that the U. S. bases on Okinawa be reinforced rather than reduced against the wishes of the Okinawans. His linking of the security of Japan with that of regional security in Asia marked a significant departure from his predecessors who had been prudent enough to confine the role of the U. S. bases primarily to the defense of Japan. It should be also noted that, given the opposition's intention to make the Okinawa problem the focal point of their political campaign, the reversion of Okinawa substantially helped smooth out the political process of extending the security treaty in 1970 by depriving them of a potentially explosive issue to mount a campaign for the repudiation of U. S. -Japan security relations based on the treaty arrangements.