I don't know, many of the privilege-libs who got involved because it looks good to care about social justice are now really truly emotionally invested and passionate about it because they went from innocent inexperienced 'ally' to a member of the police brutality victim demo.
in other words, take your average white person -> protests -> gets maced or shot for no reason -> radicalized
I wouldn't even call them radicalized. I think it's more Americans realizing that this is supposed to be the land of the free and the home of the brave and that they have to start proving themselves worthy of those titles. After all, you can't really call yourself free and brave if you just bow down to government thugs every time they launch a little tear gas your way.