Marx's complete ethos, epistemology, paradigm, dialectic and philosophy of and for the primacy of his central political theory was predicated upon class warfare: the struggle between the working class and the wealthy, and by association with the wealthy, the middle class or bourgeoisie. Distantly similar to the Identity Politics practiced by today's American Democratic Party, was Hitler's own adaptation of race warfare traded in place of Marxist class warfare, but an inter- societal race war against the Jews instead.
In order to intimately know Hitler's mind, one must read and slowly digest Mein Kampf. Hitler was fiercely tribal in his ultra passionate belief in protecting and defending the sanctity of his childhood communities, from encroachment by anyone really other than the ancient generational peoples whom he believed were the only ones who should be living there. Not only was he protective of those regions and communities, however, Hitler was also very willing to both justify doing violence to protect his beloved geographies, and, to actually do violence to meet those ends.
In my own academic opinion, Adolf Hitler's personality, both public and private, can be categorized under Moral Anti-Realism, or perhaps more specifically, Moral noncognitivism. Hitler had a moral code for himself and his inner tribe to uphold among themselves, the innermost circle and his most trusted ethnicities. Outside of that circle, however, crimes such as theft, rape, prejudicial violence, and even mass murder, were capable of being reduced to mere moral propositions incapable of being proven either true or false. Thus , and oh so conveniently for Hitler and the Nazi high-command, statements such as, "Killing is wrong" could be reduced to just "Killing" and "is wrong" could be dropped all together. What better justification could one have for mass murder—particularly when standing on the shoulders of Marx as well?