Kneeling didn't work, soooo...
Expected respondes: pass a law. Protest peacefully. Stand in front of city hall with assault rifles. Vote for (some centrist).
Just because you may not like how someone is dealing with the fact that they could be killed with no recourse by cops because of the color of their skin, doesn't mean their methods are invalid or even irrational.
The classic star wars question - is Luke Skywalker a rebel hero, or a terrorist threat to order? Before the Empire blew up an entire planet to make a point, it was a fairly valid question.
I don't know why, but as a general rule with people, if it bleeds, it leads. And that's what's worked here.