What if hitler had never been born?

Would there had been a second world war? Would it have kept the same, with hitler replace with another person from the nazi party, and WWII have gone on like normal? Would russia's push for world revolution upset the 'free' countrys to a point where WWII was brought about as a, "NATO VS COMMUNIST" war? Would there have been peace? There woulden't have been a korea or vietnam war, seeing as the communism in north korea and vietnam where caused by the land-split at the end of WWII.... what do you think?