It is good to see Gen. Galtieri forced to quit the presidency of Argentina. Thinking to escape from domestic unrest, he led his country into a foreign adventure, culminating in a shattering national humiliation. Ostensibly a patriot, he did not have the courage to take the formal step--disavowing to conduct further military operations--requisite to the speedy repatriation of the surviving soldiers whom he had sent, ill prepared, into battle. His departure in disgrace is a very small price for him to pay.

A much larger price, unfortunately, will have to be paid by Argentina. In a just world, Gen. Galtieri would have been succeeded by elements committed to ending the military dictatorship and restoring civilian rule. But Argentina seems tragically unable to sustain such elements. In his key role as army commander in chief, Gen. Galtieri was succeeded by a general known for his political narrowness and for his cruelty to civilians in the six years since the last coup. A search for scapegoats in the Malvinas affair is bound to dominate Argentina's military-based politics. The likeliest outcome of popular discontent would be a resurgence of Peronism, a form of mass sickness with no known cure.

Let 'em stew, says one school: do what can be done to make sure that Argentines do not flee, as they are prone to, from a true knowledge of what their dictatorship has done to the country. That is the way to show that aggression does not pay, this school argues, and it may even be the way for Argentina to experience the internal transformation needed to bring eventual democracy. This prescription translates into an American policy aimed at, if not punishing, then isolating Argentina. It has a vengeful ring, but some of those who wonder how else to treat the special misery of Argentina do not dismiss it out of hand.

The goals of such a policy--confession, catharsis --might be desirable. Merely to state them, however, is to indicate that Argentina is a place largely beyond the reach of conventional diplomacy. The Argentines are likely headed into a period of inner turmoil, convulsive even by their standards and tinged by the sense of Argentine uniqueness, revealed as anti- Americanism, congenial both to Peronists and generals. In those circumstances, the sensible course is to deal with Argentina in a way that allows the United States to start knitting up the hemispheric ties frayed by the Falklands war. For general Latin purposes, it would help for Mr. Reagan to make clear he prefers democrats to dictators. But this should not be done in any expectation that it will make much of a difference with or in Argentina.