"What seems an obstacle to many persons is really a preliminary condition of our victory. Just because our task is so great and because so many difficulties have to be overcome, the highest probability is that only the best kind of protagonists will join our ranks. This selection is the guarantee of our success. Nature generally takes certain measures to correct the effect which racial mixture produces in life. She is not much in favour of the mongrel. The later products of cross-breeding have to suffer bitterly, especially the third, fourth and fifth generations. Not only are they deprived of the higher qualities that belonged to the parents who participated in the first mixture, but they also lack definite will-power and vigorous vital energies owing to the lack of harmony in the quality of their blood. At all critical moments in which a person of pure racial blood makes correct decisions, that is to say, decisions that are coherent and uniform, the person of mixed blood will become confused and take measures that are incoherent. Hence we see that a person of mixed blood is not only relatively inferior to a person of pure blood, but is also doomed to become extinct more rapidly. In innumerable cases wherein the pure race holds its ground the mongrel breaks down. Therein we witness the corrective provision which Nature adopts. She restricts the possibilities of procreation, thus impeding the fertility of cross-breeds and bringing them to extinction." - Adolf Hitler, Mein Kampf
Hitler and the Nazis were totally marinated in the "survival of the fittest" ideology. Those who suggest otherwise are not paying attention to history.
Obviously, Darwinism does not necessarily lead to Nazism,
---but it does make Nazism possible.
As I said, Jew hatred was sold to the Germans with “blood upon the cross”, “international bankers”, and “mongrel blood”. They didn't try to convince them that they were the descendants of apes.