Nazis do this dumb thing where they go "hey that small and therefore relatively defenseless group (badassness of individuals aside) is the cause of all our problems, let's kill them to solve everything!"

Surprisingly, it never works.

So they do it again with somebody else, and somebody else, and somebody else, until everybody on earth is killed by nazis or somebody stops them.

As for why anybody is dumb enough to fall for it in the first place...it's anybody's guess.