FOR EVERY HAITIAN, from the taxi driver to the peasant, the two most important dates in history are 1804 -- the establishment of Haiti as the first black republic -- and 1934, the end of American military occupation. Those dates, repeated over and over on radio and in newspapers, are a passion, a unifying force for the troubled island.

So it was hardly to be expected that a country so proud of having thrown out white foreigners would burst into an orgy of flag-waving "Vive l'Amerique" chants in front of the American embassy on the day dictator Jean-Claude ("Baby Doc") Duvalier fled into exile.

The Reagan administration supplied the pressure for Baby Doc's ouster. It was a classic example of American interventionism without the use of American troops. But, unlike other historical non-military meddling in the region, it was a case that won nothing but praise -- from Haitians themselves to begrudging liberals in this country.

The full extent of U.S. involvement is not yet clear. But even if the American campaign went no further than what was overt, the pattern demonstrates a strong U.S. role in the dictator's ouster.

As early as last Thanksgiving, U.S. diplomats were putting out the word that they thought Duvalier couldn't last. When street protests escalated in January, $52 million in aid was suspended. White House spokesman Larry Speake's inaccurate announcement at the height of the protest that Duvalier had been ousted was widely intrepreted in Haiti as a sign that the United States would not be sad to see him go. Then Secretary of State George Shultz said the United States wanted to see democratic elections in Haiti, and it was all over.

The story of how a conservative Republican administration came to intervene on the side of human rights to force out a repressive regime is particularly poignant now that the administration is grappling with the Philippines. And the old question of whether to disengage totally from Haiti as a protest, or stay involved and use money as leverage for change, is a debate that could have ramifications not only in Manila, but in Johannesburg.

Comparisons between countries are always problematic, the parallels imprecise. But examining the specifics of Haiti can teach lessons on the use of American influence, while demonstrating how a broad consensus can sometimes develop on the side of U.S. intervention abroad.

In Haiti, three dynamics came into play in the early 1980s, before the mass street protests and ensuing repression made obvious what Haiti-watchers had known for years: The government there had to change -- or be changed by the United States. It was the combination of all three that shifted the Reagan administration from an attitude of benign neglect to a champion of human rights.

The Reagan shift was motivated, first and foremost, by the scene of Haitian exiles showing up by the thousands on the shores of Miami, flooding South Florida with a pool of unskilled black refugees, illiterate even in their strange language (Creole), straining the social safety net. That refugee influx made U.S. intervention not a case of moralistic crusading, but pure and simple American self-interest.

There was also a heightened concern about official corruption diverting the flow of U.S. aid dollars into the Swiss bank accounts of Duvalier and his cronies -- corruption that was base even by Third World standards. Stealing local tax dollars is one thing, but selling plainly labeled U.S. gift rice on street corners is a step too far.

Third was an unusual coalition of liberals, members of the congressional black caucus, and the new U.S. ambassador, Clayton McManaway, whose shared concern over human-rights abuses led to tougher aid requirements, over State Department objections.Those dynamics were played out against one peculiarity that made Haiti's dictator unlike repressive counterparts elsewhere: Jean-Claude Duvalier, who inherited the presidency-for-life from his father, had been in the position for 15 years and had accumulated vast wealth. He lacked the passion for power of a Marcos or a shah or a Somoza, according to some who knew him. This made it easier to talk him into leaving.

"Money was always more important for Jean-Claude than power," said one former aide. "Money for his father was a way of keeping power. Power for Jean-Claude was a way of making money."

Haiti's geography is significant in the case for intervention because it is less than 60 miles from Cuba, raising the specter of an uprising there that could be coopted by communism. Havana radio regularly beams broadcasts in Creole, and thousands of Haitian exiles now reside in Cuba, their rickety boats never having made it all the way to Miami. No one has claimed a communist force behind the largely unorganized popular movement to oust Duvalier, but neither has anyone denied the possibility that the small (less than 300-member) Haitian Communist Party later might try to take some of the credit.

The proximity to the United States is more relevant. Packed into small boats, Haitians can easily navigate the 700-mile trip north to Miami by using the tightly-packed Bahaman islands as stepping stones, to break up the journey into manageable chunks. More than 600,000 Haitians had fled to U.S. shores by the end of Reagan's first year, escaping the poverty of the island and providing a badly needed safety-valve for its exploding population.

The influx led the administration to order U.S. Coast Guard cutters to begin intercepting the boats at sea, and they used the threat of a U.S. aid cutoff to get Duvalier to cooperate and help stem the human tide. But at the same, time there was a recognition in Washington that something had to be done to tackle the root problem: the misery that the refugees were fleeing.

Faced with the continuing economic misery compounded by Duvalier's often brutal repression -- with reports that returning boat people were systematically arrested, beaten and tortured -- Congress in 1982 admonished Haiti to observe "basic human rights," and tied aid money to continuing improvement on human rights issues.

Throughout that period of the early 1980s, two schools of thought developed among congressional Haiti experts, prominent exiles, and administration policy-makers. The first was the "pull the plug" school, which said Duvalier's regime was beyond reforming and the best way to express U.S. disgust was to cut all aid money. The second school of thought said that the United States had a moral responsibility to help; that the aid cut-off would only hurt the island's impoverished masses. According to this line, aid money should bypass the government and be given to private, voluntary organizations, while U.S. policymakers continued to push for incremental change.

The path of pushing for "incremental change" has typically come to mean turning a blind eye to repression. But congressional critics of Haiti found an unexpected ally when the U.S. ambassador there, Ernest H. Preeg, was replaced two years ago by Clayton McManaway.

Working together, McManaway and congressional staffers toughened the language on Haiti's aid-certification progress, making free labor unions and democratic reforms a new requirement for U.S. aid, and then earmarking $1 million for a literacy program, at a time when the Duvalier regime was cracking down on the Catholic Church's literacy program there.

Now that the ousting of Baby Doc seems to be the textbook case on how to build a broad consensus for successful intervention, the tendency for American policymakers might be to try to take a hand in the shaping of the government that comes after Duvalier. To follow that tendency would be to misread the Haitian example, and ignore the significance of 1804 and 1934.

"We still have a sensitivity about solutions dictated from abroad," said Leslie F. Manicat, exiled head of Haiti's National Progressive Democrats. "We want to have our own Haitian solution, but one that will be accepted by the United States."

He added: "When you see Haitians with American flags, it means they want the friendship of the U.S. But I'm not sure they'd want another U.S. military intervention."