The ideological and political goals that Hitler formulated in 1924 in Mein Kampf formed the basis of his politics after 1933. And here, above all, it was his Weltanschauung – grounded in a blend of anti-Semitism, biologistic racism, and vulgar Social Darwinism – that was of decisive importance. In Hitler’s mind, the history of humankind was marked by the constant, ruthless struggle of various civilizations for preeminence. According to him, racial purity was the most important precondition for victory, whereas racial mixing, especially with Jews, weakened a people internally and doomed it to certain destruction. To save the German Volk from this fate, Hitler propagated the need for "de-miscegenation" [Rassenentmischung]. That this idea resonated with Heinrich Himmler (1900-1945) can be gleaned from the marginal notes in his personal copy of Mein Kampf (vol. II). Penned in 1927, his comment reads: “die Möglichkeit der Entmischung ist vorhanden” [“the possibility of de-miscegenation is at hand”]. Five years earlier, Himmler had earned a degree in agriculture, and many scholars regard his early training, specifically in animal husbandry, as the stimulus for his later preoccupation with racial breeding. After seizing the reins of Nazi population policy, Himmler would become one of the most radical proponents of state-sponsored eugenics.
The paragraph marked by Himmler reads: “Jegliche Rassenkreuzung führt zwangsläufig früher oder später zum Untergang des Mischproduktes, solange der höherstehende Teil dieser Kreuzung selbst noch in einer reinen irgendwie rassenmäßigen Einheit vorhanden ist. Die Gefahr für das Mischprodukt ist erst beseitigt im Augenblick der Bastardierung des letzten höherstehenden Rassereinen.”
It is translated as follows: “Every racial crossing leads inevitably sooner or later to the decline of the hybrid product as long as the higher element of this crossing is itself still existent in any kind of racial unity. The danger for the hybrid product is eliminated only at the moment when the last higher racial element is bastardized.” [Adolf Hitler, Mein Kampf. Translated by Ralph Manheim. Boston: Houghton Mifflin Co., 1999, p. 401.]