Name a country that has a black minority that harbored racial grievances, but later relinquished them.
YEP!
The tragedy is that that country might have been the United States.
During the sixties, the MLK approach was gaining major ground, and as racial animosity dissipated in the glow of the general prosperity, the Left went ballistic.
Racial divide was to be the primary tool of the Left in crippling America, and here this damn King was making black people and white people become friends... which is why the left, not the right, hired a flunkie to assassinate Martin Luther King and blame it on "White America."
It was only after that the Black separatists and other antagonists gained the upper hand and set the black community back about fifty years.