What if Nazi Germany did not invade Poland?

[Gaius Sempronius Gracchus]

Largely a pipe dream I think.

The Soviets were just too big (and advanced) at the end of WW2; largely due to American aid.

While the Soviets did the majority of dieing in WW2 they still had more where that came from. The US would have had to "carry the ball" for the Eastern war, and I don't think the population would have stood for it. In addition, without time for retrenchment the Allies logistics would have collapsed. It is an interesting "what if" but I just can't see the needed popular support for extending WW2 much beyond where it finished.

Well, exactly. You've hit the nail on the head. Of course US national sentiment wouldn't have stood for it - nor was there too much appetite for extending the war within an already ravaged Europe. That is the thing with any what ifs - there is usually a reason why it remained a what if rather than an actual event. The reasoning was sound, but there were stronger reasons (cons) considered at the time which out-weighed the pros.