WE GOT IT wrong in this space the other day concerning the state of play of South African sanctions legislation in Congress. It is true that both the House and the Senate have passed legislation and that their conferees have agreed on a relatively modest bill. But the bill, though on its way to Mr. Reagan, has not yet been sent. Final action is still pending in the Senate. Our point was and remains that there is a broad enough general consensus among moderates, within the administration as well as among many of those arguing for sanctions, to arrive at a clear and strong American position -- as distinct from bogging down in a self-absorbed fight over whose variation on that position may be the right one. Nothing that has happened in South Africa in the past several days has changed our view of that.

It is good news that the president's national security adviser, Robert C. McFarlane, has been putting new pressure on the South African government to move away from its abominable racial policies. Later this week we will see what the results of that pressure are. Meanwhile, there is one minor refrain on this subject that needs a little attention. As the predictable violence in South Africa has grown, one begins to hear people saying that the bloodshed and turmoil in fact tend to justify the repression of the South African government, that they demonstrate that South Africa's racial majority is not fit to participate in self-government.

Black Africa -- not just that part under Pretoria's control, but all of it -- has long been subject to a special standard in this connection. We suppose a case could be made that Hitler's Germany and Stalin's Russia indicate that whites are not ready for self-rule. But no one extrapolates that way where white people are concerned; the sweping conclusion is saved for the African case. Oddly, when you read about tribal warfare among other races -- in Lebanon or Indochina -- the idea of the tribe is seen as something different. So is savagery on the part of large numbers of people who turn on each other and on those in authority: In South Africa this is viewed as primitive; in Londonderry it is viewed as tragic.

The South African government has long been good at interpreting the unhappy effects of its own rule as vindication of that rule. It strips vast numbers of black people of their freedom, of their capacity to earn a living, of an opportunity to learn and of a chance even to live with their own mates and parents and children. Then it says to the world, "But look, they don't know how to govern themselves, they are unschooled, they do not live the same way we do -- what are you asking us to do?" It cites the violence most surely generated in large part by its own protracted, systematic repression as evidence that the blacks under its rule are not responsible people.

But the terrible internal violence in South Africa is not evidence that the white government's apartheid policies are right. It is evidence that they are wrong and must be changed.