LIKE SUPPLY-SIDE economics, the Reagan Doctrine of never-ending warfare against pro-Soviet regimes in the Third World is the product of a small coterie of conservative thinkers and activists.

Mainly as a result of their ideological campaign, more than half a billion dollars is being spent annually by the CIA to equip 80,000 to 100,000 "freedom fighters" with everything from boots to Stinger missiles. And last week, the House of Representatives voiced its approval of the Reagan Doctrine by passing $100 million in military aid to the Nicaraguan contras.

Prominent among those in the crusade for the Reagan Doctrine have been White House Communications Director Patrick Buchanan; former National Security Council staffer Christopher Lehman at the consulting firm of Black, Manafort, Stone and Kelly; columnist Charles Krauthammer; Under Secretary of Defense Fred Ikle; professional adventurer and right-wing culture hero Jack Wheeler; Sen. Orrin Hatch (R-Nev.) and other members of the Senate's Republican Steering Committee; and retired major general John K. Singlaub, head of the World Anti-Communist League.

But the most important and enduring name is that of the man who defined the concept for them all, James Burnham, an ex-Trotskyist who wrote a column called "The Third World War" for years in the National Review and demanded an armed rollback of communism in Eastern Europe.

Burnham's influence has "profoundly affected the way America views itself and the world," according to the citation on the Medal of Freedom bestowed on him on Feb. 23, 1983. "And I owe him a personal debt," President Reagan observed at the ceremony, "because throughout the years traveling the mashed-potato circuit I have quoted you widely."

On the right, where a certain kind of anti-communism is a part of ideological faith, "Burnham" can be a kind of password.

Consider: Richard Nixon is president. He and his entourage are in Key Biscayne, Fla. A young speechwriter is swimming laps in his pool. At the pool's edge, a stout man wearing swimming trunks and carrying a heavy pile of thick books sits down.

"So, you are the hardliner?" calls out Henry Kissinger.

Patrick Buchanan looks up from the water and nods.

"You know," Kissinger says, "Burnham was basically right."

According to Burnham, a choice confronted America in the Cold War -- either "appeasement" or "liberation." By posing the question so starkly, he helped set the whole litmus-test tone for the conservative movement. The crisis had begun at Yalta, Burnham and the right believed. There, Eastern Europe had been handed over to the Soviets -- an act of appeasement. Among those he classified as "appeasers" were Secretary of State Dean Acheson; George Kennan, the diplomat who originated the "containment" policy' and "foreign service officers of the type."

Burnham's seminal contribution to conservatism was the strangest twist in the tortuous history of Trotskyism. Burnham transformed Trotsky's theory of "permanent revolution" into an imperative of permanent counterrevolution. And Trotsky's charge that the revolution had been betrayed by Stalin was turned into a charge that the counterrevolution was betrayed by Franklin D. Roosevelt at Yalta.

The belief in betrayals led to a belief in loyalty tests. Who lost China? Vietnam? Iran? Nicaragua?

The moment of truth came in 1956, when the Hungarians rose in armed revolt against the Soviets. "Liberation was a sham," wrote Stephen Ambrose in his biography, "Eisenhower."

"Eisenhower had always known it . . . which made all the four years of Republican talk about 'liberation' so essentially hypocritical."

Burnham leaped to Eisenhower's defense, arguing that his inaction was "part of the reality of our time." But he soon reverted to his old formulas, which remained unchallenged as conservative dogma. (A few years ago Burnham suffered a stroke and is incapacitated.)

With the failure of the theory of "rollback" in Eastern Europe, the scope of the Reagan Doctrine has been limited to the Third World, rendering futile its ultimate goal of overthrowing communism by force. No one has made this point more manifest than Reagan, when he resumed shipments of wheat to Russia and ended the economic restrictions against Poland.

The words "Reagan Doctrine" have never been uttered by Reagan himself, nor by Shultz. "We don't like to call it a doctrine," said an administration official. "We open ourselves to criticism if we pretend we have a doctrine, imposing it on complicated reality."

But the doctrine has been hailed by the right, from the think tanks to the columnists, as the grand concept of the president's second term. "Ronald Reagan is the master of the new idea," proclaimed Charles Krauthammer, the neoconservative columnist, who first labeled what Reagan was doing a "doctrine."

"We had him (Krauthammer) in for an off-the-record lunch with the president," said an administration source. "He popularized the term, a rallying point for conservatives."

"I love that guy Krauthammer for inventing 'Reagan Doctrine,'" said the adventurer, Jack Wheeler.

Pressure for adherence to the Reagan Doctrine, however, has not come simply from outside the administration; it has also come from within, particularly from Under Secretary of Defense Ikle, a former Swiss seminarian who applies the Burnham catechism to the contemporary struggle for the world.

"Containment has been outflanked," he said in an interview. "It worked in Korea, it worked in Europe, but it doesn't work in the Third World." In a recent speech, Ikle denounced any effort to "contain communism within Nicaragua" as "a terrible idea." The true choices, he explained in another echo of Burnham, are either "appeasement" or "freedom."

Ikle's speech was given in January at the Low-Intensity Warfare Conference, sponsored by the Department of Defense, one of the many conferences he has funded.

According to a list of recent contracts on low-intensity warfare released by the Pentagon, $587,000 has been granted to the Rand Corp. alone, where Ikle was the former director of social sciences. The subjects studied include rebel movements in Angola, Afghanistan, Ethiopia Nicaragua, and "Commando Raids: 1939-1980," the situations that the Reagan Doctrine focuses on.

While those promoting the doctrine dream of a communism-free universe, their closer goal is to ensure that no Republican will be nominated for president who has not pledged fealty to their ideology.

"It works well inside the church of the Republican Party in dealing with heretics," said a leading conservative about the Reagan Doctrine. "Angola and Nicaragua, these are very important tests. They became tests of orthodoxy and validity. The Reagan Doctrine is very useful for the movement."

In Congress, a center of Reagan Doctrine support has been the Republican Steering Committee, a weekly caucus of New Right senators, who in turn are surrounded by aides who maintain constant contact with New Right organizations and exile pressure groups, from Free Angola to the Committee for a Free Afghanistan. The successful lobbying to repeal the Clark Amendment, which forbade covert intervention in Africa, was the Steering Committee's first test case. The visit of Angolan "freedom fighter" Jonas Savimbi was another.

The doctrine supporters' lobbying was applied with particular pressure on Senate Majority Leader Robert Dole (R-Kan.).

"If he's interested in the White House he realized this was a litmus test of conservative support," said a congressional source. "So he met with Savimbi." On Feb. 6, Dole signed a letter to Shultz written by Christopher Lehman, the lobbyist who handled the $600,000 Savimbi public relations account. The letter requested "weaponry" and was signed by 11 senators, and soon a cargo of Stingers was headed Savimbi's way.

"If Dole had stood in the way," said a congressional source, "it would have been political suicide."

The most recent test of the Reagan Doctrine, of course, has been military aid for the contras, another loyalty test. "With the vote on contra aid," wrote Patrick Buchanan on March 5 in The Washington Post, "the Democratic Party will reveal whether it stands with Ronald Reagan and the resistance -- or Daniel Ortega and the communists."

Whether the doctrine succeeds as a foreign policy, it is already working as a domestic political device by which the conservative elite exercises its influence. Low-intensity conflict abroad has triggered high-intensity politicking at home. To that degree, what is called the Reagan Doctrine is actually a condition of American politics -- a condition as old as the Cold War.

Sidney Blumenthal covers politics for The Washington Post.