Chicken or egg? Maybe they have become racist white supremacists as an extreme response to feeling under attack for being white males?

 Hate comes from fear. Fear comes from feeling threatened. 

We have had a few decades now of whites, particularly white males, being accused of all the world's ills, and even the mainstream media has been gloating over their disappearance as "brown people" take over. Presumably because the latter's innate moral superiority will usher in a utopia of freedom and equality...That could just be enough to send the more emotionally fragile young people over the edge...