Because the whites have already been destroyed. If you throw a rock at wealthy powerful whites, you’re overwhelmingly likely to hit a “white”.

This is part of the reason why leftists are so rabidly anti-Trump. He is popular among poor whites. Leftists can’t target this demo based on class, so they needed a different attack factor. What if those poor whites are all Nazis? Now we can commit unrestricted social, financial, and physical violence against them!