THE United States is interested in what happens in South Africa. There are three reasons:
1. There are 26 million blacks in the US. They are increasingly active and influential politically. They care about what happens to blacks in South Africa.
2. South Africa is an important trading partner of the US. South Africa is the world's largest producer of gold, vanadium, aluminosilicate, chrome ore, diamonds, ferrochromium, and manganese. It produces 80 percent of the world's manganese. (The Soviet Union produces 14 percent.)
The US buys more from South Africa and sells more to South Africa than any other country. Britain is a close second in both directions of trade. West Germany is third. Japan is fourth.
3. South Africa is strategically important in East-West military rivalry. It is known in military parlance as one of the ``choke points'' in world strategy. Anyone who controls South Africa can control shipping around the Cape of Good Hope, and naval movements.
For these three reasons the US is interested in the future of South Africa and must hope for, and work toward, a future there that will be friendly to the US. At the very least, South Africa must not become a client and partner of the Soviet Union.
The problem for Washington is how to adjust its behavior toward South Africa in a manner that will avoid a gain for the Soviets.
Ideally (for the US) there would be a gradual and bloodless transition from white rule to shared black-white rule with a mixed government friendly to the United States.
There are ample lessons in recent history in how to conduct oneself in a situation like this. In China and Vietnam, the United States backed the ultimate losers. By backing the loser in China, the US delayed the break between Russia and China for 22 years. By backing the loser in Vietnam, the US bought itself the Vietnam war.
It is difficult for the US not to back the ultimate loser in civil war situations. Social and business relations have been built up with the old upper classes. The revolutionaries tend to be unknown in Washington. They didn't go to Yale or West Point. They are disturbers of the status quo and strangers.