Nakasone, Yasuhiro (yäˌsŏhēˈrō näˌkäsōˈnā) [key], 1918–, Japanese political leader and prime minister (1982–87). He served in the Diet after 1946. A political ally of Kakuei Tanaka, Nakasone succeeded Zenko Suzuki as prime minister. He increased Japan's military strength and established closer ties with the United States and with China. He resigned in 1987, and retired from the Diet in 2003.