Isn't that the game where Japan never attacks America and the Nazi's invade once they've successfully overrun Britain and the USSR?
I was hoping you would've included the Star Wars project in your answer... I found your answer to be pessimistic, honestly. No offense, I'm just too American to accept defeat, be it by Nuclear Holocaust or the hand of commies.
Anyway, to answer your question, the already strained Nazi war-machine would fail to successfully occupy America, and we would counter-attack their fleet, followed by Britain, and then France and into Germany itself.
What if WWIII were to happen soon? As in N.A.T.O./India/South America/Australia vs. Russia/China/Middle East (not Isreal)/ Africa? (I think we'd win, since Canada and the U.S. from N.A.T.O. could just starve all of those countries to death anyway... but it's up to you, really)