Which 1945 Allied plan was intended to capture the Kanto Plain near Tokyo?

Operation Coronet was the planned Allied invasion of the Kanto Plain near Tokyo.

Coronet formed the second stage of Operation Downfall, following Operation Olympic’s proposed invasion of southern Kyushu. Planners expected Coronet to begin in spring 1946, after Olympic had created airfields and secured a major base area. The Kanto Plain was strategically important because it contained Tokyo and much of Japan’s political and economic power.

Japan surrendered before either stage could begin. Consequently, Coronet was never tested in battle, and its projected troop requirements and casualty estimates remain historical planning figures. The plan’s name is sometimes confused with Downfall, but Downfall was the umbrella operation and Coronet was one of its two component operations.

The planned assault reflected Allied expectations that Japan might continue fighting despite naval blockade, bombing, and the destruction of several cities. Japan’s acceptance of the Potsdam Declaration in August 1945 ended the need for the invasion.