Following recent police shootings of black men who were unarmed, pinned down, or apparently above suspicion, “Black Lives Matter” gained more credibility than any such movement had in the past.

Its tactics and demeanor had not suddenly become endearing — it conspicuously hadn’t — but a wider swath of the public came to see that it identified a real problem and not all the cases it cited were as baseless as that of the thug, Michael Brown, whose death sparked the movement in the first place.