The claim that Hitler and Stalin were atheists, and committed their crimes against humanity because of their lack of belief in a Deity, is not borne out by Hitler's own writings and speeches, which are peppered with references to God and His divine plans for the German people. Unless Hitler was a completely cynical hypocrite, he must have believed at least some of this. He had been, after all, brought up as a Catholic.
For instance, after the Reichstag fire Hitler, with Goering, Goebbels and von Papen, inspected the smouldering ruins and said to Sefton Delmer, the Daily Express correspondent who was also present, "This is a God-given signal, and if this fire, as I believe, turns out to be the handiwork of Communists, then there is nothing that shall stop us now crushing out this murder pest with an iron fist. You are witnessing the beginning of a great new epoch in German history."