Question for the board. From what I've read of the proposals for Operation Downfall (the planned invasion of Japan), the forces earmarked for Downfall vastly exceeded the U.S. forces that took part in the D-Day invasion. Operation Downfall was to involve 42 aircraft carriers, 24 battleships, and 400 destroyers on the naval side. On the army side, 14 divisions were to take part in the initial landings, with 42 divisions to take part in Operation Coronet later. So my question is, could the U.S. have implemented as large or nearly as large a force for the Normandy invasion?
To answer my own question, I'm guessing an armada of 42 aircraft carriers and 24 battleships create severe logistical difficulties with being deployed in the English Channel, not to mention that such a fleet would not really be needed to cross the Channel to France, while it was probably necessary for the Japanese invasion. But what about the army divisions allocated for Operation Downfall? Is there a reason the U.S. couldn't or didn't contribute as many army divisions for D-Day as it planned to for Downfall? Was it that America was still fighting both Germany and Japan in 1944 and didn't have the forces available, whereas with Downfall the U.S. only had to worry about Japan? Those are just some guesses off the top of my head. Anyone know the answer to this?