FAMILY & FRIEND VETERANS OF FOREIGN WARS

While the war was being fought in the Philippines and Okinawa, plans were ripening rapidly for the largest amphibious operation in the history of warfare. "Downfall," the grand plan for the invasion of Japan, contemplated a gargantuan blow against the islands of Kyushu and Honshu, using the entire available combined resources of the army, navy, and air forces.

 

The plans for "Downfall" were first developed early in 1945 by the Combined Chiefs of Staff at the Argonaut Conference held on the tiny island of Malta in the Mediterranean. On 9 February, just a few days before the historic Three-Power meeting at Yalta, President Roosevelt and Prime Minister Churchill were informed of the conclusions reached at Argonaut. At that time, the strategic concept of future operations in the Pacific embodied the defeat of Japan within eighteen months after Germany's surrender and included the following series of proposed objectives:

 

a. Following the Okinawa operation, to seize additional positions to intensify the blockade air bombardment of Japan in order to create a situation favorable to:

b. An assault on Kyushu for the purpose of further reducing Japanese capabilities by containing and destroying major enemy forces and further intensifying the blockade and air bombardment in order to establish a tactical condition favorable to:

c. The decisive invasion of the industrial heart of Japan through the Tokyo Plain.1

 

On 29 March, the U.S. Joint Chiefs of Staff, working on the assumptions that the war in Europe would be over by 1 July 1945 and that the forthcoming Okinawa operation would be concluded by mid-August of 1945, set a tentative schedule for the invasion of Japan. The invasion plan was assigned the cover name "Downfall" and consisted of two main operations: "Olympic," the preliminary assault on the southern island of Kyushu, which was slated for 1 December 1945, and "Coronet," the subsequent landing on Honshu, which was scheduled for 1 March 1946.

 

It was proposed that forces already in the Pacific be used to the fullest extent possible in planning for the assault and follow-up phases of "Olympic." Reserve and follow-up divisions for "Coronet" would be obtained by redeployment, either directly or via the United States, of troops and equipment from the European Theater.

 

On 3 April 1945, the Joint Chiefs of Staff issued a directive in which General MacArthur was instructed to complete the necessary operations in Luzon and the rest of the Philippines, prepare for the occupation of North Borneo, and "make plans and preparations for the campaign in Japan." The amphibious and aerial phases of the projected Homeland invasion.