What was the proposed second stage of Operation Downfall, aimed at Honshu near Tokyo?

Operation Coronet was the proposed second stage of Operation Downfall, aimed at Honshu near Tokyo.

The plan was designed to follow Operation Olympic, the planned invasion of Kyushu. Coronet was scheduled for 1 March 1946 and would have placed Allied forces on the Kantō Plain, the broad region surrounding Tokyo. The objective was to capture the capital area and force the Japanese government to capitulate if earlier operations had not ended the war.

Operation Downfall was never executed. Japan’s surrender announcement in August 1945 and the formal signing in September removed the need for an invasion of the home islands. Coronet consequently remained a planning document rather than a battlefield operation.

The proposed invasion is often discussed alongside debates about the likely human cost of continuing the war. American and Japanese planners prepared for heavy resistance, drawing on the experience of battles such as Iwo Jima and Okinawa. However, estimates of possible casualties varied widely, and no actual Coronet campaign occurred.