The reviews of Ronald Reagan's Central America spectacular were predictable. Supporters welcomed the ringing rallying cry against the encroachments of international communism. Critics thought the stakes the president was piling on the table were all out of proportion to either the threat or to this country's capacity to deal with it on the president's terms: a heavy application of military aid, but no U.S. combat involvement, and no real vote of confidence in the potential for diplomacy.

While counting myself in the latter camp, I suggest, in fairness, that Reagan is by no means the first president to go for the quick and cynical fix --the presidential "prevent defense" dictated less by sound policy for the long haul than by electoral exigencies.

Item: John F. Kennedy was thought of as a pretty high-minded, longheaded student of international affairs. But for him the question of what to do about the Dominican Republic after the slaying of the arch-tyrant Trujillo in May 1961 came down to three choices, according to Arthur Schlesinger Jr.: "a decent democratic regime, a continuation of the Trujillo regime, or a Castro regime." And the answers: "We ought to aim at the first, but we really can't renounce the second until we are sure that we can avoid the third." Jeane Kirkpatrick could hardly quarrel with that.

Item: Lyndon Johnson was similarly haunted by "another Cuba" when he sent U.S. troops into the Dominican Republic in 1965. "What is important," Johnson said, "is that we know, and that they know, and that everybody knows, that we don't propose to sit here in our rocking chair with our hands folded and let the communists set up any government in the Western Hemisphere." That analogue might have better served Reagan's speechwriters than did their citation from President Truman, speaking in 1947 about the security of the advanced societies of Western Europe.

Item: Alternatively, consider Vietnam. Secretary of State Dean Rusk once defined a realistic Johnson administration objective as that of being able to turn the problem over to its successors "in no worse shape than we found it." Later, Richard Nixon blustered that he did not intend to "be the first president to lose a war." That distinction, as it turned out, was bucked along to Gerald Ford--with the rooftop evacuation of the last Americans from the Saigon embassy in 1975.

This strategy of the "prevent defense" runs through Reagan's Central America rhetoric--and the private comments of his advisers as well. He tells us the terrible things that will happen in Central America and around the world if El Salvador falls, but offers no more than a promise that the awful day can be postponed.

What the president was pledging was not so much success as the absence of failure. For a definition of success, you had to turn from the House chamber last Wednesday to the office of the U.S. Ambassador to El Salvador. There, that very day, Deane Hinton was telling Washington Post reporter Christopher Dickey that the real solution to that tormented country's problems --notably the military's human rights abuses--is "a question, in my view, of years." He was saying that El Salvador's salvation would require "a generational change" in the army's officer corps.

Ronald Reagan's White House advisers are working to a different clock. And so, to be sure, are many in Congress who would not like to be identified in election year 1984 as the real culprits, if their denial of the president's money requests for military aid could plausibly be held accountable for El Salvador's collapse.