Sure. But if all Hitler had was his personal hate, he could not have killed millions of people. That required a vast, rationally organized bureaucratic system. Without that system, the Holocaust could not have occurred. I've used this example before, but it's worth repeating: a greedy person in a hunting and gathering society cannot institute a capitalist economic system, no matter how much he wants to, because the important social constituents of capitalism do not exist in that type of society (e.g., production of a significant economic surplus). Capitalism is not simply a product of individual psychological characteristics; it is a precipitate of social relations and conducive social structures.
And just so with the Holocaust: any explanation that hinges on the psychological characteristics of people is a nonstarter, because the Holocaust was the product of a complex ensemble of social relations. Without conducive social structure and technology (e.g., bureaucratic organization, mass transportation, recordkeeping), the Holocaust would have been impossible, Hitler's vicious hatred notwithstanding.
Miles