Originally Posted by
Marsilius
Er... oh, yes they did, I'm afraid. The USA didn't enter the war by choice but because war was declared on them (a) by Japan attacking at Pearl Harbor, and then (b) by Hitler declaring war on the USA (not the other way around). The USA may have been generally sympathetic to the anti-Axis cause before December 1941 but it was dragged into the conflict willy-nilly. It didn't enter the war on principle at that point but because they had no choice over whether to do so or not.