I’d say what @LapsedPacifist has already said, but with the addition that we have tried being nice and polite and it got us to where we are today, with Trumpism and Brexit.
You cite the black power salute, but would white people have considered Martin Luther King Jr a more moderate voice without Malcolm X? The black power salute was controversial in the 60s and considered to be threatening to the status quo.
You give the Rainbow flag as an example, but I would remind you that the first pride was a riot.
The ‘punk rock’ anarchy symbol is an example of capitalist recuperation, not success (and I say that as someone who has a lot of respect for genuine anarcho-punks). Besides that, anarcho-punks are not pacifists.
I have read Tolstoy and his writings on non-violence and civil disobedience (the same book that influenced Gandhi and MLK), but I disagree with him. While non-violence should always be the starting point of protests, it should not be a rule set in stone. This is especially true when people are dying as a result of the actions that we are protesting against.
ETA: And since I have just mentioned Gandhi, let me direct you to another national hero of the Indian Independence Movement
Bhagat Singh became a popular folk hero after his death. Jawaharlal Nehru wrote about him, “Bhagat Singh did not become popular because of his act of terrorism but because he seemed to vindicate, for the moment, the honour of Lala Lajpat Rai, and through him of the nation. He became a symbol; the act was forgotten, the symbol remained, and within a few months each town and village of the Punjab, and to a lesser extent in the rest of northern India, resounded with his name.”
