I dont see how Hitler stops-he cant. His whole stucture of power, his essence of being was centered around that past experiences and histories of war were now moot;that this new, quick, lightning war was NOW and before anyone could counter it, he had to get what he could. Blitzkrieg could work in the small, numerous, countries in Europe but it could not work in the endless steppes of Russia, nor could it bypass the 21 mile wide river. If Hitler stopped after France, then what-the guy was on a roll, momentum was with him... If he stopped, he has very limited raw materials to work with, while RUssia is growing and growing-learning about OPERATIONAL WAR-learning how to trade space for time. Hitler's Germany was designed for quick conquests to secure land (living space) and resources-without the resources of Russia where would Hitler have turned?