- Thomson, Max
- History - WW2
- RAN Ships
- None noted.
- September 1999 edition of the Naval Historical Review (all rights reserved)
Now DECLASSIFIED, only a few Americans back in 1945 ever were privileged to have access to a plan which, to this day, few Americans – and fewer Australians – still know about.
Buried deep for decades in the US National Archives in Washington, thousands of yellowing, dusty pages marked TOP SECRET now reveal the enormity of OPERATION DOWNFALL – the proposed invasion of Japan.
Atomic bombs dropped on Hiroshima and Nagasaki brought the Japanese to heel – and to unconditional surrender.
After that all interest in a plan for invading the Japanese homeland became obsolete.
The incredible story of the grandiose planning for American forces to invade Japan has been summarised by James Martin Davis following a study of the so-secret material once it was DECLASSIFIED from top secrecy.
Two massive military undertakings were planned. They were to be carried out in succession – OPERATION OLYMPIC on Nov 1 1945 and OPERATION CORONET on March 1 1946.
In the first invasion, combat troops would be landed by amphibious assault after an unprecedented naval and aerial bombardment. Fourteen combat divisions of American soldiers and marines would land on heavily fortified and defended Kyushu, southernmost of the Japanese home islands.
The second invasion, in the following March, would send 22 more American combat divisions against one million Japanese defenders to assault the main island of Honshu and the Tokyo Plain in a final effort to obtain unconditional surrender.
With the exception of a part of the British Pacific Fleet, it would be a strictly American operation – (though it is reasonable to assume that ships of the RAN operating for so long with Task Forces of the US 7th Fleet most probably would have participated).
In his summation, James Martin Davis states the overall plan called for use of the entire United States Marine Corps, the US Navy in the Pacific and for use of the US 7th Air Force, 8th Air Force recently deployed from Europe, the 20th US Air Force and for the American Far East Air Force.
More than 1.5 million combat soldiers, with millions in supply would be directly involved in the two amphibious operations.
A total of 4.5 million American servicemen – more than 40% of all still in uniform in 1945 – would be involved.
One US Admiral estimated there would be some 250,000 Americans killed or wounded on Kyushu alone. A General estimated American casualties from the entire operation would be one million men by the fall of 1946.
As the invasion grew imminent, the massive power of the United States Navy would approach Japan – two awesome fleets, the Third and the Fifth.
For several days battleships, heavy cruisers and destroyers of those fleets would pour thousands of tons of high explosives into targets as a prelude to the launching of the land invasion forces.
During the early hours of Nov 1 1945, thousands of American soldiers and marines would pour ashore all along the eastern, south eastern, southern and western coasts of Kyushu.
The Eastern Assault Force, made up of the 25th, 33rd and 41st Infantry Divisions would land near Miyaski at beaches called Austin, Buick, Cadillac, Chevrolet, Chrysler and Cord; moving inland to capture the city and its airfield.
The Southern Force, consisting of the 1st Cavalry Division, 43rd Division and others would attack beaches named Dusenberg, Essex, Franklin and others, to try and capture Shibushi, then the city of Kanoya and its airfield.
On the Western Shore of Kyushu at beaches named Pontiac, Reo, Rolls Royce, Saxon, Star, Studebaker, Stutz, Winton and Zephyr, the 5th Amphibious Corps would land Marine Divisions 2, 3 and 5 sending half of its force to Sendai and the other half to Kagoshima.
On Nov 4 the reserve force consisting of the 81st and 98th Infantry Divisions and the 11th Airborne Division would be landed near Kaimondake at the southern tip of Kagoshima Bay using beaches designated as Locomobile, Lincoln, La Salle, Hupmobile, Moon, Mercedes, Maxwell, Overland, Oldsmobile, Packard and Plymouth.
If all went well with that initial OPERATION OLYMPIC, then OPERATION CORONET would be launched on March 1, 1946 – again involving massive US combat forces twice the size of the initial operation and using as many as 28 Divisions on Honshu, the main Japanese island.