Yes, we should emulate the example of Mandela. Be humble, forgive, move on. But also, we should remember, that the U.S. was a long-time friend of apartheid, and friends to the oppressors that ran South Africa.
And yes, the Conservative Right was wrong about apartheid, and South Africa and sanctions for a very, very long time. They were the useful idiots and they were kind of a star-studded group - names like Ronald Reagan, Jesse Helms, William F. Buckley, Jerry Falwell, Pat Robertson - they actively worked against sanctions and helped keep apartheid in place… a rogues gallery of rogues.