Could the Allies have won WWII in Europe if the US had stayed truly neutral?

Well, for beginners, I’m a semi-holocaust denier. (NO, I can’t explain what the semi-Holocaust was…I just have my doubts that the Genocide thing occurred the way we’ve been told) But, that aside, if there was a Holocaust, I believe that it was Himmler inspired, and Hitler may never have known about it.
*If *there was a Holocaust, and *if *Hitler did know about it, it’s my understanding that German genocide (by actual definition of ‘-cide,’ not the UN version) against the Jews wasn’t codified until the 40s.

Point being, he wasn’t irrational. Maybe mean, but, not irrational, given his own standards of morality.

Best wishes,
hh