Which phase of Operation Downfall planned the invasion of Japan’s main island near Tokyo?

Operation Coronet was the planned invasion of Japan’s main island near Tokyo.

Coronet was the second phase of Operation Downfall, following the proposed invasion of southern Kyushu known as Operation Olympic. Planners expected Coronet to begin in March 1946 after Allied forces had secured Kyushu and built up supplies, airfields, and reinforcements.

The proposed landings focused on the Tokyo Plain, with operations around Sagami Bay and the Boso Peninsula. The area was strategically important because it provided access to Tokyo and other major political and industrial centers on Honshu. Planning documents assigned large formations of American troops and included possible Commonwealth participation.

Coronet never occurred. Japan announced its acceptance of the Allied surrender terms in August 1945, making the projected invasion unnecessary. A frequent mix-up is to call the entire invasion plan Coronet; the correct relationship is that Downfall was the overall plan, Olympic was the Kyushu phase, and Coronet was the Tokyo-area phase.