<P> After the Korean War began in 1950, Douglas MacArthur, the Supreme Commander for the Allied Powers in Japan and the Japanese government established the paramilitary "National Police Reserve," which was later developed into the Japan Self - Defense Forces . </P> <P> In 1951 the Treaty of San Francisco was signed by the allied countries and Japan, which restored its formal sovereignty . At the same time, the U.S. and Japan signed the Japan - America Security Alliance . By this treaty, USFJ is responsible for the defense of Japan . As part of this agreement, the Japanese government requested that the U.S. military bases remain in Japan, and agreed to provide funds and various interests specified in the Status of Forces Agreement . At the expiration of the treaty, the United States and Japan signed the new Treaty of Mutual Cooperation and Security between the United States and Japan . The status of the United States Forces Japan was defined in the U.S.--Japan Status of Forces Agreement . This treaty is still in effect, and it forms the basis of Japan's foreign policy . </P> <P> In the Vietnam War, the US military bases in Japan, especially those in Okinawa Prefecture, were used as important strategic and logistic bases . In 1970, the Koza riot occurred against the US military presence in Okinawa . The USAF strategic bombers were deployed in the bases in Okinawa, which was still administered by the U.S. government . Before the 1972 reversion of the island to Japanese administration, it has been speculated but never confirmed that up to 1,200 nuclear weapons may have been stored at Kadena Air Base, Okinawa in the 1960s . </P> <P> As of 2013, there are approximately 50,000 U.S. military personnel stationed in Japan, along with approximately 40,000 dependents of military personnel and another 5,500 American civilians employed there by the United States Department of Defense . The United States Seventh Fleet is based in Yokosuka, Kanagawa Prefecture . The 3rd Marine Expeditionary Force (III MEF) is based in Okinawa. 130 USAF fighters are stationed in the Misawa Air Base and Kadena Air Base . </P>

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