This beating is “tough to watch,” said the news anchor. But when it comes to black on white violence caught on video, that does not narrow it down much. This one is in Lexington, Ky., from WLEX news. “And we do warn you: Some may find the images disturbing.” But hardly unique. The reporter was introducing her viewers to a recently released video of black man attacking a white college student waiting for a bus. The assault begins with a close-up of the man who is about to ask the college student for a cigarette. When the student says no,...