Which planned Operation Downfall phase targeted Japan’s Kanto Plain near Tokyo?

Operation Coronet was the planned Operation Downfall phase targeting Japan’s Kanto Plain near Tokyo.

The Kanto Plain surrounds Tokyo on the main Japanese island of Honshu. Coronet was intended to follow Operation Olympic, the proposed invasion of Kyushu, and was scheduled for spring 1946. Airfields captured during Olympic were expected to provide support for the advance toward the Tokyo area.

Coronet was cancelled before it began because Japan surrendered in August 1945. The planned invasion therefore remained a military contingency rather than a battle or campaign. Its cancellation also meant that the expected casualties and destruction associated with an invasion of the densely populated home islands did not occur.

Operation Coronet is sometimes confused with Operation Downfall itself. Downfall was the overall invasion plan, while Coronet was its second major phase. The first phase, Olympic, targeted Kyushu.