@Drnaline,
"But Hitler was raised Catholic."
So what? He wasn't a Christian. He cast off that particular childhood influence. Instead, he grasped at a powerful, competitive religion, endemic to the German nation -- blood-and-soil, pre-Christian
tribalism.
"That was what most committed Catholic Nazis were."
What? That sentence doesn't make sense to me.
"Though 'Catholic' in name, if they truly believed in the Nazi cause, they were in conflict with Catholicism."
That's what I'm saying. Nazis chose their ancient, pre-Christian tribalism over Christianity. It made sense in historical terms. The Germans were the last major barbarian people to convert to Christianity, and they were the fiercest opponents of Rome. Yes, they eventually succumbed, but they put up one helluva fight, thanks to their cultural intransigence and unity.
"I think lack of a religious moral basis could be said to be the real force behind the mass murders of history, not atheism in and of itself as the cause."
Nazism's ethos was based on hardcore social Darwinism. They viewed the German people as a racially superior, naturally stronger people, empowered and obligated by nature itself to annihilate the weak, taking possession of all available living space, replete with its rich natural resources, in the establishment of an inconquerable, ever-lasting empire.
"It was more often a political ideology that included atheism so that no religious values could conflict with it."
Yes, but Hitler did believe he was possessed, in an abstract way, by the spirit of the German people.
PS: Let me chime in with a few of our fellow posters by citing my academic achievements. While earning my 12th PhD at Harvard/Princeton/Yale (of course I'm joking), I concluded that although Hitler was indeed demonic, he was perhaps the most fascinating leader of modern history.