The most interesting thing about this article is that it leaves out all the interesting stuff. I recommend googling one Dr David Kelly, and a young fellow called David Cameron who would become better known later. When the US and UK learned RSA had the bomb, and the ANC were about to inherit it, they were suddenly a lot less enthusiastic about the incoming administration they had previously endorsed.
It is as simple as that. They read the writing in the wall and knew that the native would take back power. They didn't trust, and want, the native blacks to have nuclear weapons. The whites in Africa still have deep political ties with the Anglo-Americans, and that's why we see Trump complaining about "white genocide" in South Africa.