SOMETHING RITUAL, reflexive and off the point has seized the debate about South Africa in this country. People seem more interested in totalling each other's arguments and in justifying their own prior political biases than they do in trying to understand what is going on there and what this country's position should be. Every cliche in the book has been trotted out. Empty theorizing runs riot. It is lots of fun. But it is reckless. This country needs a clear, strong, broadly agreed-upon -- yes -- bipartisan policy toward South Africa, its government and its turmoil. It is a measure of the self-absorption and confusion reigning at the moment that even this self- evident proposition is held in doubt.

There is nothing we can do, so we should do nothing -- this is an ony slightly exaggerated form of an argument one increasingly reads and hears. It is made most often by conservatives, and it rests almost entirely on reasoning that conservatives themselves deride when it is hurled at them from the other side during arguments over how this country should react to various Soviet outrages. Left and Right are still at it, only they have had a kind of cultural exchange of their own: each side has stolen the other's arguments. Nobody seems ashamed.

These arguments -- overstated, extreme -- do not stand up a whole lot better in the South African context than they do when applied to East-West matters. They have the same unmistakable aspect of debating points that may or may not have anything at all to do with reality. Thus we find conservatism arguing about President Botha (as liberalism is wont to do about whoever is Soviet Party secretary that year) that, thuggish as his acts may look to some, he represents a considerable breakthrough toward decency and reform, that to push him in any respect is to endanger him with the "hard-liners" in his own camp and to show, as said hard-liners have always argued, that reasonableness doesn't pay.

A variation, which conservatives have hooted down when it was made by their liberal opponents in relation to taking tough action against places from North Vietnam to Nicaragua, is that tough action will only unify the country around its presiding villain and thus work in the opposite way from that intended. And besides, add a few of these folks whose instinct for interventionism is generally strong (and sound), it's surely none of our business how they organize their affairs in South Africa. Finally there comes what the Right, in another context, denounces as "moral equivalence," that insistence on seeing both sides at fault no matter how towering the crime of one may be in relation to that of the other under discussion.

Hold the mirror up to this and you will see how those who can provide you with any number of impassioned arguments as to why we should follow a policy of "constructive engagement" toward the Soviet Union, no matter what it does, and who are often indifferent to or doubtful about its brutalities, have reversed polemic course just as thoroughly as their antagonists have.

At about this point you will hear the nuclear holocaust argument made. Those who are forever arguing that to get tough in any respect or any degree with the Soviets over anything is to invite almost certain obliteration of the planet will protest that the Soviet case is a special one. But the apartheid pacifists among us have their own variation on this ultimate threat. Again and again one will hear that the risk in pushing Mr. Botha is that the world will end up with a brutish black African anarchy on the Ugandan model. There is a little of the when-you've- seen-one-you've-seen-them-all mentality to this. But it is also true that no one can look at the political and economic condition of most of the newly liberated countries of black Africa and hope that South Africa minus apartheid will end up like them.

The point is, however, that, just as it is possible (and necessary) to press the Soviets on questions of human rights and political subversion and aggression without inviting nuclear war, so it is possible (and necessary) to press the white apartheid government of South Africa to abandon its institutionalized cruelties without inviting a nightmare of anarchy. Mr. Botha would like you to think otherwise. He and his government keep putting forward these two false alternatives: leave us alone or risk the total disintegration and impoverishment of the land. But the real alternative to what he is doing is to end a system of gratuitous cruelty and oppression visited on people for no other reason than their race. It is the continuation of that system, more than anything else, that is likely to bring on precisely the violent debacle he purports to be warding off. Conservatives who understand that abject appeasement is likelier to lead to nuclear war than to avert it should not have so much trouble understanding that the same is true in relation to the South African version of the holocaust that they envision.

The white South African government, famous for its habit of gunning down peaceful protesters for over a quarter of a century now, has resisted every inch of the way taking those steps that could ameliorate the system, always giving too little and too late. It is sometimes noted in distinguishing South Africa from various totalitarian and authoritarian states that certain elements of democratic openness are present there as compared with other tyrannies. This is true, but it hardly extenuates the gun-enforced mass racial repression. Rather, it suggests that pressure may have some response. On moral and political grounds, it seems to us, there is an obligation for this country, on which Pretoria so greatly depends, to press it to take advantage of what remains of the opportunity to reach a just and stable solution. This country does have power; it does have influence; it does have responsibility; it does have urgent cause to act while there are still parties around with whom the Botha government can deal. Isolation, abdication, the big shrug would be criminal.