Taboos around violence for political are one of the crucial building blocks for a functioning democracy. If those taboos are broken, even for a good cause, you set a precedence that violence works. And the next cause won’t be as good. One only has to look at the lessons of the Roman Revolution that started with the murder of Grachus, and ended with an Emperor who everyone acclaimed as they were so tired of the bloodshed.
The non-violent protests of Colin Kaepernick were mocked and used to rally the other side and just weren't effective.
The problem here is not the violence, but a policing system that is so fundamentally damaged and has not been effectively reformed fast enough.
The MLK quote is trotted out pretty often, but "a riot is the language of the unheard".
Trotted out by ignorant woke dummies. In his 1967 Stanford speech MLK also says: "Let me say as I've always said and I will always continue to say, that riots are socially destructive and self-defeating. I'm still convinced that nonviolence is the most potent weapon available to oppressed people in their struggle for freedom and justice."
Using MLK to defend or advocate violence is astonishingly ahistoric.
For example:
"X is a bad person, therefore their argument is invalid" is an ad-hominem. Bad people can still make valid arguments.
"X's argument is both invalid and in bad faith, therefore they are a bad person" is a logical inference.
It is the difference between "If you believe X then your school must have had brain-dead teachers" and "If you believe X you are brain-dead"