FIFTY-FOUR WEEKS AGO, 376 days ago, 12 1/2 months ago, three American nuns and an American missionary left El Salvador International Airport in a white Toyota van, bound, as it turned out, for a shallow grave 15 miles to the northeast. Though the National Guard had claimed thousands of victims in the years and months before, the point blank shots to the back of the head that killed the four churchwomen were, for the war in El Salavador, the shots heard round the world, or at least the Western Hemisphere.

Five years of American involvement in Vietnam--of soldiers dying, lots of them--elapsed before sustantial numbers of people began making a substantial amount of noise; by contrast, the news of our much less direct role in El Salvador's stunningly brutal repression was swift, loud, and over-whelmingly angry. The Reagan administration had hoped to commence a new sort of cold war foreign policy in the Central American nation. The State Department declared in February that El Salvador was a "strikingly familiar case of Soviet, Cuban and other Communist military involvement in a politically troubled Third World country." But Americans, especially Democrats, Catholics, liberals and leftists, ignored the White Papers, the "captured documents" and the other lies. Mail to the White House ran eight-or ten-to-one against American involvement; when a small leftist group used to be calling 50 people a big crowd pasted up a few posters about El Salvador, they drew 5000 to the Boston Common; Walter Cronkite wouldn't ask Reagan about anything else during a midwinter interview; even at Harvard it took only 90 days for a big, and by 1980s standards militant, crowd to gather for a rally.

Yet the spasms passed as quickly as they had come. When was the last time you heard much about El Salvador? Not this fall, if you read major U.S. newspapers, or listen to the networks, or look for demonstrations. For a few months, the reports of atrocities were regular; now it takes a full-scale massacre to get an inside column in The Times. Reasons abound for the sudden lack of interest; the list, though, does not include improvements in the El Salvadoran situation, which seems largely unchanged.

Recent visitors to the country report that rebels continue to control about 25 per cent of the nation. The Farabundo Marti Front for the National Liberation (FMLN) has not won much new territory in recent months; it has not, despite large-scale attacks employing U.S. firepower, lost any ground. Within the "liberated zones," some institutional structures--primary education, food distribution and medical care--have begun to emerge. Rebel intelligence is apparently effective; word of planned army incursions reaches the resistance leadership in time for entire villages to be moved.

In the rest of rural El Salvador, the repression from the right continues. When the insurgents declared that they, like their Vietcong predecessors, would swim like fish in an ocean of peasants, Salvadoran leaders announced their determination to "dry up the ocean." Bodies still pile up by the roadways each night, and the terror has created tens of thousands of refugees and thousands of would-be refugees who were killed before they could flee. In the capital city of San Salvador, a "superficial calm" prevails, one visitor reports. It is a calm that almost surely will not last past March, when "free elections" are scheduled in the country. Four new right wing parties, including one headed by the grisly Roberto D'Aubuisson, have joined the campaign, which the left is boycotting; the ultrarightists are complaining about Christian Democrat policies, and their presence in the election will help insure that the "creeping coup" fron the right continues. Meanwhile, resistance grows; Col. Adol Arnoldo Majano, for example, has spoken out in recent weeks against the Duarte government he once served. He has said President Duarte pretends he cannot control the death squads of the right. In reality, Majano insists, Duarte has never made any attempt to assign responsibility for the killings, presumably because any investigation would thoroughly discredit his internal security forces.

American aid to the country continues; American officers--50 of them, about ten per cent of all officers in the Salvadoran military--continue to train troops, and many sources continue to contend that American Green Berets and special forces troops really run the show. Certainly, the counter-insurgency techniques resemble those used in Vietnam. The latest U.S. policy statements, in late summer, indicated support for Duarte's 1982 election plan, and opposition to negotiations with the rebels, the course so many European nations have advised. How valid elections can be held when public opponents of exploitation are routinely murdered was not explained. Enough, the State Department says, that El Salvador is "committed to democracy."

CHANGE, THEN, HAS NOT COME to El Salvador. It's been in America, and among Americans of every political bent, that the shift in feeling has taken place. We've all but forgotten the conflict that for a few months occupied much of our attention.

Skillful manipulation by the Reagan administration is one reason. Its efforts to paint the insurgents as pro-Soviet, Cuban-sponsored Marxist-Leninists met with some success in the early months of 1981. The State Department White Paper of February 23, 1981, for example--an authoritative-sounding treatise based on a confusing and contradictory pile of "captured documents," for instance--went unchallenged by the press for almost three months until John Dinges of the tiny Pacific News Service published a masterful demolition of their content and conclusions. Though readers of the Washington Post and the Wall Street Journal had a chance to read in midsummer about the dubious value of the White Paper, most of America was left to assume that our military advisers were standing up to the Kremlin in the mountain jungles of Morazan and Chalatenango.

Histrionics, tantrums and murky intelligence reports have become the watchword of Reagan's foreign policy, and they serve well to obscure topics like justice and poverty. The current uproar over Libyan "hit squads"--of whose existence not one shred of evidence has yet been offered--is tailored to frighten. Circle the wagons, or so the reasoning goes.

But the blame for most of our short memory belongs on the shoulders of American liberals and leftists, the Democratic Party, and our religious leadership. They've let the issue, as they've let many other like it, disappear. It is an old axiom that only the threat of American deaths will arouse American concern; El Salvador seems a case in point. Four dead Yankee Catholics and everyone noticed. "Military advisers," a phrase that sounded like Vietnam, and everyone noticed. "No Draft, No War, U.S. Out of El Salvador" was the most popular chant during Harvard's mid-March demonstration, perhaps for more than its pleasing rhyme scheme.

When Reagan, apparently surprised by the hullabaloo, told Cronkite, "I certainly don't see any likelihood of us going in with fighting forces," the movement began to wither. For another month or two, and on this campus for another three, people seemed to stay concerned and active. But then the liberal's own Vietnam syndrome--the readiness to forget about the disease as soon as the worst symptoms clear up--took over. There were other causes: nuclear weapons, for one. And Reagan was up to other games: His budget cuts drew all eyes for a few weeks. But more than that, El Salvador didn't matter anymore. Except that thousands were being murdered, thousands more starving, and American shipping in copters and ammunition and claymore mines and advisers and even 30,000 boxes of Crations.

Forgetfulness for whatever reason is an unforgivable sin for the American left, for it mirrors too closely the greed-induced myopia of our country's post-World War II foreign policy. El Salvador--indeed all of Latin America--provides a textbook case of this phenomenon, a classic example of the wrongheaded shortsightedness that loses us almost every Third World friend we have.

For generations, the American government paid no attention to El Salvador. Through all the generations its people suffered silently, and through all the recent years when they tried to stand up for a little justice and were shot for their pains, the only people who knew about the nation were the executives of companies like Texas Instruments, Chevron, Phelps Dodge, Kimberly-Clark, Texaco and Crown Zellerbach. Any time in the last 40 years, some carefully applied American pressure might have spawned major reform. Probably anytime, that is, until March of last year, when a rightist gunman shot and killed Archbishop Oscar Romero as he celebrated Mass. Perhaps anytime until November 28 of last year, when six leaders of the Democratic Revolutionary Front were assassinated. Maybe, though probably not, even today. As the crisis deepened, more decisive action would have been necessary. Instead, the Carter administration fooled around at the edges, offering the Salvadoran military, in the words of former ambassador Robert White, "goodies," in return for reductions in the level of repression. And then came Ronald Reagan, maybe the biggest bully in our history, and his State Department couldn't wait to give the Salvadoran government anything it wanted. They "rushed in headlong to prove how macho they were," White says.

Iran, Nicaragua, and half a dozen countries in recent years prove the unsoundness of our policy toward Third World dictatorships. Always, we all but ignore the practices of these governments as long as they remain our friends. Always--Russians or no Russians, Cubans or no Cubans, Libyans or no Libyans--the people of the country wake up, gain courage from some depth of faith, some heroic example, some pitch of opression too horrible to bear. Always, the people quickly make the connection between American and their dead brothers and uncles and their empty tables and their dirty clothes. Usually, our government then begins ot request some token reforms from the regime in question; never are they enough to redress the social and economic problems; if they have any effect at all, it is the opposite of their intent, the weakening of the government. Sometimes, as with the Reagan administration, our government opts to back the "friendly" despot to the hilt. No matter; in either case, the people eventually win, though only after much bloodshed, much sacrifice, much bitterness.

STRATEGICALLY, AS HAS BEEN SAID so often, the policy makes no sense. Whatever the ideological leanings of the rebels--and usually they lean toward the full stomach and the healthy body--we push them towards the idiot inflexibilities of Russia. We did it to Cuba; we are doing it to Nicaragua; almost surely we will do it to El Salvador, and then Guatemala, and then Honduras, and on and on. Poor countries need someone to help them out, and though the Cuban example has proven that reliance on Moscow and a totalitarian economy is not fiscally sound (and there are at least solid rumors that Castro has been urging the Sandinistas and the Salvadoran rebels to avoid his mistakes) these countries will look for help where they can get it.

"Morally," of course, such conduct makes even less sense. That we can ignore the misery of other nations for decades when it is within our power to do something about the conditions, or at least within our power not to support the oppressors, says much for the underdeveloped soul of this country. All we can offer, too little and always too late, are the mild reforms, cough syrup for the patient with double pneumonia. In El Salvador that cough syrup has been "land reform," the supposed distribution of the country's acreage to the peasants who farm it. Rammed down the throats of the Duarte regime by American officials desperate for some improvements to point to, land reform has been so far a frustrating and occasionally lethal business, as a series of essays in a superb new book, El Salvador. Central America in the Cold War (Grove Press; $7,95), makes clear.

Roy Prosterman, the veteran of the Vietnamese "land reforms" who masterminded the El Salvadoran program (and whose visit sparked the Harvard protest last spring) contributes one of the tracts, arguing that his land reform is likely to be the only land reform for a very long time. "Those who really care about El Salvador's peasants will, I think, join me in urging that economic aid to the land reform be continued," Prosterman contends, basing his argument on the announced goals of the three-phase land reform program.

A consultant to the Inter-American Development Bank, Peter Shiras, describes the real state of the "reform": the first phase, the expropriation of the largest estates, was in large measure subverted by landlords; the second phase, which dealt with medium-size estates, indefinitely postponed; and the third, "land to the tiller" phase hopelessly mired in a bureaucratic maze. The right wing will not allow significant reforms, and, Shiras reports, government troops often interfere. He quotes one government official as saying: "The troops came and told the workers the land was theirs now. They could elect their own leaders and run the co-ops. The peasants couldn't believe their ears, but they held elections that very night. The next morning the troops came back and I watched as they shot every one of the elected leaders." The reforms have been part of a "rural pacification" program, described by Shiras as a "carrot and stick" approach to building support for the existing regime. "The land reform program cannot be divorced from the political context in which it takes place, just as U.S. economic aid cannot be neatly separated from military aid--both are tools to prop up a government directly responsible for the deaths of over 12,000 of its own citizens last year." Leonel Gomez, a former official in the land reform program, adds land reform has strengthened the hand of the military, "whose sole concern is for increased U.S. military and economic aid, for increased power, and an increased ability to rule, to kill, and to corrupt." The story of El Salvadoran land reform is the story of a score of other U.S. efforts in other countries--piecemeal change offered when the time for piecemeal change has passed, a last-ditch attempt to keep the ruling elite intact.

The "ignore-repression-until-it's-too-late" policy makes neither tactical nor humanitarian sense; there is no great mystery about whom it benefits, however. The short-term economic interest of a few major companies and the geopolitical imperatives of a few ideologues have been well served. Though direct American investment in El Salvador is now only about $100 million, it and other Central American nations provide a substantial market for subsidiaries of U.S. companies. And the "hit list" theory propounded by Secretary of State Alexander M. Haig holds that the advance must be checked at every turn or there will be dire consequences for the free world and the natural gas fields of nearby Mexico. If one holds that the El Salvadoran government--and most of the other governments of the region--are intolerably repressive, it is a damning indictment of our multinational economic system. Like pathetic Britain in the dying days of her empire, we are wringing dollars out of, quite literally, the blood of peasants.

Our government's willingness to forget about El Salvador makes sense; it fits with everything one would expect from the historical record of our foreign policy. And the forgetfulness of the left, or liberals, of the Democratic party, is not really shocking, for it also matches historical patterns of laziness and neglect. The second phemonenon--the amnesia of the left--will have to be cured before the first--the government's moral and strategic blindness--can be cured. Until it does, the cycle of crisis-alarm-forgetfulness will continue. Fifty-four weeks is a damn short stretch of time.