A good article and conversation with a reader.

Government has an obligation to the public to put down riots. Government is force and force will be met with greater force. The agents of the state sent to put down the riots do not enjoy the luxury of understanding or sympathizing with the cause of the protest. The only concern is the rioters. Rioting is a fool's errand. Mostly peaceful is not a consideration, only the violence of the riot is.

Protest, even when non-violent, has the issue of agitators showing up to ruin the protest by making it a riot. But even without that, if you want people to listen to your issue, don't spit in their eye. That's how you start a fight.

Back during the civil rights movement, seeing the police sic dogs on the protestors painted the police as bad guys and garnered sympathy and cooperation for the cause. Arson, looting and other forms of violence paints the protestors as the bad guys, making a desire to cooperate with their cause less likely. I think that the non-violence approach of Dr. King had a better affect than violence would have had.

Interestingly, TV shows like All in the family, the Jeffersons, etc. were a force for displaying the absurdity of racial bigotry and it's less likely to piss off people who are laughing. Sadly, those helpful jokes are a thing of the past.