Re:

Have been off mail and am slowly catching up with a deluge.

He's right that the sports boycott, mainly rugby, really hit home. But there is more to say. After the sanctions and boycotts really hit home, the supporters of apartheid were confident, for a simple reason, which was quite explicit: they were counting on the US to support them, and if it did, recognized that the rest of the world didn't matter. And in fact Reagan supported them to the end of his term, the last holdout in the world. Not long after the US joined the rest of the world and apartheid collapsed. But there were reasons why the US did so: Cuba. Cuban forces drove South African aggressors out of Angola, compelled them to abandon illegally held Namibia, and made it clear to them that their hope for dominating the region couldn't be realized. And there also was a solution acceptable to South African elites and to Washington: keep the socioeconomic system in place and allow some black faces in the limousines.