Yet all of them achieved their successes primarily by the persuasion of their oppressors, generally in strong moral terms.
No. Like, just no. Mahatma "British rule was established in India with the co-operation of Indians and has survived only because of this co-operation. If Indians refuse to co-operate, British rule will collapse" Gandhi was not running a moral persuasion campaign, and neither was MLK with his boycotts and army of lawyers. I will also note that the Civil Rights Act of 1968 was passed after and due to riots after MLK's assassination. And that's not getting into how the Civil Rights Movement was immensely aided by the existence of violent black power groups. You should really learn more about this stuff if you think moral persuasion was the main factor in any of this.