It's just that whites have moved out in mass from their ethnic ghettos long time ago. At one time it was whites picking on and whooping on blacks and latinos for fun, then white flight happened, and they got docile, and blacks and latinos got hard from years of police harassment and crackin each other's heads.
I mean there are places where you have large groups of ethnic whites (Irish, Italian, Russian,etc) in the US but that's the only place I've seen shit like that.