It isn't limited to Black Americans, by any means.
A phenomenon I noticed during the High School race riots I endured in the late 60s/early 70s was that when the black kids got away with being unruly because no one would challenge them to avoid a racial incident, it didn't take long for the white kids to say "Hey, I have equal rights, too!" and become similarly unruly.
That breakdown in civility was not conducive to getting an education, at least not the sort we were ostensibly there for.
That was within the relatively closed society of a 1200 student school.
Let this nonsense continue in society at large, and it is only a matter of time.