Honshu was the planned target of Operation Coronet near Tokyo in 1946.
Coronet was the second stage of Operation Downfall, the proposed Allied invasion of Japan. Its objective was the Kanto Plain on Honshu, the large island containing Tokyo. The operation was tentatively scheduled to begin on 1 March 1946, after the planned invasion of southern Kyushu under Operation Olympic.
Planners expected Coronet to be larger than Olympic. The initial assault was to involve American forces landing around Sagami Bay and the Boso Peninsula, followed by a drive toward Tokyo and surrounding areas. The operation was intended to bring the main Japanese political and industrial center under Allied control.
Japan’s surrender in August 1945 made Coronet unnecessary. Honshu should not be confused with Kyushu, which was the target of Olympic, or Okinawa, where a major battle had already taken place. Honshu is Japan’s largest main island and remains the location of Tokyo.