On July 7, the Japanese foreign ministry released 37 classified documents related to the reversion of Okinawa and the 1960 revision of the security treaty with America.
One of the documents contains the minutes of a meeting between U.S. and Japanese officials held on November 26, 1958. During the meeting, U.S. officials basically pressured Japan into revising Article 9, which prohibits Japan from using force to resolve international disputes.
Another one of the documents contained the minutes of a meeting held on May 27, 1968. During that meeting, the U.S. ambassador told Japan that North Korea monitored U.S. military capabilities in the region and that America needed to have nuclear weapons in Japan to deter North Korea.