Re: @nematoad ... Also...
"Can you say Flying Tigers?"
Yes I can. I can also say that the Flying Tigers were mercenaries in the employ of the Nationalist Chinese government.
Look, there were some US citizens actively engaged before 1941. The 3 RAF Eagle squadrons come to mind, but my point was that the US has always talked and acted as if nothing really happened until after Pearl Harbor. Quite apart from the fact that as other here have said the Soviet Union played a huge part in bleeding the Third Reich to death.