The Pacific War

 Hollywood in the 1930's

Hollywood stopped portraying the Chinese as evil in the late 30's with threat of war with Japan, the last thing the USA needed was the two enemies to join in one army. It would have been Fu Manchu's dream, an indestructible army, consider the number of soldiers who would have died. I wouldn't have been surprised if the US would've been forced to surrender; they had enough with Japanese in the Pacific War.