GUINEA, AN AFRICAN nation the size of Oregon and the repository of perhaps one-third of the world's bauxite reserves, experienced a unique revolution last April 3 that attracted too little attention. Once thought to be "lost" to the communists, long a cockpit of cold-war intrigue, Guinea has been turned around by middle-aged army officers who staged a coup and declared themselves anti-Marxist and pro-free enterprise.

These officers seized power one week after President Sekou Toure died in an American hospital after a quarter century in power. They began their revolutionary reign by freeing all political prisoners and posting the U.N. Declaration of Human Rights on public buildings.

What's more, this joyous liberation from 26 years of Toure's erratic tyranny was accomplished without either bloodshed or the participation of a single U.S. Marine, Army Ranger or even military adviser.

Perhaps this lack of American involvement helped blind us to the significance of an event we ought to be studying with some care. What happened in Guinea was the sort of thing we should expect from Africa, where the countries are just one generation old, and are still feeling their way toward an identity that is unlikely to have much to do with either of the superpowers.

I must confess to a special interest in Guinea, where I was the American ambassador in the first years of the New Frontier. Guinea was my reward for service as a speechwriter for John F. Kennedy during the 1960 campaign. The new administration offered to give me a government job, and I volunteered to become our ambassador in Conakry -- the malarial, scabrous, dilapidated capital of a country then teeming with Soviet bloc missions and widely regarded by most of our pundits and senior cold warriors as "hopelessl down the drain."

Hardly a choice post, there were of course no other applicants to go there. I remember a friend remarking, "You must have written some lousy speeches to be sent to that dump."

But at 41, I was young enough to be attracted by the challenge of trying to prevent the emergence of another Cuba on the strategic tip of Africa's west coast. (In those days, all of us, liberals included, were gung- ho cold warriors). Also, I wanted to test my theory that no self-respecting political leader relishes being a puppet -- least of all a proud, shrewd and magnetic leader like Sekou Toure. And if he was sincerely non- aligned in his political orientation, should we not offer him the means to wriggle out of the tightening Russian embrace?

When I arrived in Conakry, the Soviet bloc was busily constructing a 100-kilowatt transmitting station, an elaborate polytechnical institute, a huge printing plant and 6,000- foot jet runway -- all too big for Guinea's needs but not for a base for subverting West Africa. Very few Soviet projects made sense. A tomato cannery was erected where no tomatoes were grown, and heavy machinery -- including winterized grass-cutters that looked like snow plows -- came by the boatload and quickly broke down for lack of maintenance and spare parts. Communist advisers had infiltrated the entire bureaucracy and practically ran the Ministry of Information.

But some long talks with Toure convinced me he was restless and uncomfortable with this influx of foreign technicians and Guinea's growing dependence on barter agreements that he didn't quite understand. I notified Washington, and Philip Habib, then in charge of a section of the State Department dealing with communist economic affairs, flew over to examine the landscape and learn more about the unexploited bauxite -- from which aluminum is obtained -- in the northwestern part of the country.

A week later we both went to Washington with the outline of a modest aid pacage emphasizing manpower training, agricultural development, transportation and light industry. We got speedy approval at the White House, where the mood was more innovative than at the State Department, which was still Europe-oriented and reluctant to take any initiative in Guinea without French approval. And Habib taught me how to navigate though the bureaucratic shoals: we wrote my instructions, and for three days walked them from office to office, securing the necessary initials and saving at least two months' of paper processing.

Back in Conakry, I was able to show Toure that Americans delivered on their promises and could move fast; also, that he could count on us if the Russians let him down or got too pushy and possessive. In effect, we provided Toure with a little freedom of movement; and in fact, within six months he felt free enough to expel one of his chief benefactors, Soviet Ambassador Daniel Solod, for engaging in activities -- meetings with Guinean citizens -- deemed subversive to Guinea.

Except fot the Federal Republic of Germany, no other Western country was doing anything in Guinea, not even the French who, while partners in the consortium operating the nation's one profitable industrial enterprise -- the privately-owned FRIA alumina plant -- were still "punishing" Guinea for having rejected De Gaulle's offer of quasi-independence in 1958.

And so the cold war percolated in Guinea for years. But our relations with Toure remained correct, except for a brief explosion of anti-Americanism in 1966 over a misunderstanding involving the detention in Ghana of Guinean officials traveling aboard a Pan American plane.

Despite our initial cold war anxieties, the Russians eventually lost interest in Guinea, as they have in most of Africa. Their probes and thrusts during the '60s into Algeria, Morocco, Egypt, Sudan, Mali, Ghana, Equatorial Guinea, Congo (Brazzaville), Zaire, Somalia, Kenya, Tanzania, Zanzibar and Uganda have all run out of gas.

They are bogged down (because they are involved) in the fractious misery of Ethiopia. Mozambique is drifting back to the West (it even came to the Olympic Games), and Angola would like to if it didn't need the Cubans to keep Joseph Savimbi's Pretoria-backed rebellion in check. About the only area of the continent that the Soviets still watch with interest is South Africa, where they hope the U.S. will somehow end up backing the doomed white supremacists against black Africa when the inevitable showdown comes, as it almost surely will.

The Russians never did understand Africans, who not only exasperated them by their nonchalance but who also regarded them, not inaccurately, as racists. During the Cuban missile crisis of 1962, the Soviets were not allowed to use Conakry airport as a refueling stop to Havana even though they had built the runway.

I had secured Toure's personal assurance on this and was therefore surprised at the height of the crisis to find a huge Tupolev- 114 jet transport parked on the apron when I went out to the airport to say goodbye to Sen. Allen Ellender (D-La.), who just happened to be passing through Conakry on one of his annual junkets to exotic and photogenic places.

The senator was travelling in a U.S. Air Force DC-3, which was parked next to the Russian jet. While he and I chatted by the plane, my wife was approached by the first secretary of the Soviet embassy in the departure lounge.

"If you will tell me what that American plane is doing here," he said, "I will tell you something that will interest your husband."

She explained about Ellender's periodic jaunts, and told him the plane was the senator's. "Thank you," said the Russian. "And now I can tell you that the Tupolev is not enroute to Cuba, as your husband probably suspects, but to Brazil in order to fetch the body of the Soviet ambassador, who died this week."

And so it was. We got confirmation the next day that the Soviet aircraft had landed in Recife.

The informality that prevailed in Conakry's diplomatic community often saved us all a lot of time. The only holdouts against the general conviviality (nourished by shared hardships and frustrations) were the Chinese and North Koreans, who were even fussy about whom they shook hands with at receptions. The Chinese ambassador was my neighbor, and we used the same strip of narrow beach for our daily noontime swim. But the only time he spoke to me in 18 months was when I warned him one day, in French, of a nearby jellyfish. "Merci," he replied.

The airport was also the scene of continual comic intrigue and "misunderstandings" -- a word frequently used in West Africa to explain a colossal snafu without hurting anyone's feeling. One day I was summoned to the airport security office where a tourist from the transit lounge was being detained for having taken photographs in violation of regulations and then struck the policeman who arrested him.

"Excellence," said the police captain, "Please tell your compatriot that he has committed a serious offense that we cannot allow to go unpunished."

The culprit, attired in shorts, flowered shirt, golf cap and dark glasses, was both drunk and surly. Not the kind of American we needed in Guinea at that particular time.

"Where are you from?" I asked.

'Windsor, Ontario," he replied.

Smiling, I turned to the captain. "Your prisoner is not an American," I said. "It is not my affair."

"But look at him" protested the Guinean. "It is evident he is an American!"

I told him appearances were sometimes deceiving, and went back to the terminal, where I found Donald Logan, the British ambassador, who represented Canadian interests in Guinea.

"Donald," I said complacently. "You have a problem. In the security office."

I left Guinea in 1963, after opening an American commercial exhibition and greeting Pan American's inaugural flight to Conakry. It had been a busy two-and-a-half years for me, including a bout of polio, but Toure appeared to have mellowed and relaxed. When I saw him again in 1966, he drove me to his seaside villa, unaccompanied by bodyguards, police escorts or even a chauffeur. I guess he wanted to show me how confident he felt about his own security and his people's loyalty. He even stopped at red lights and chatted with pedestrians. And I confess I was impressed.

But later Sekou Toure became increasingly paranoid -- especially after an attempted invasion by armed exiles from Portuguese Guinea in 1970. In the backlash that ensued, most of the best men and women in his government were arrested, tortured, hanged, shot or confined in the infamous Boiro prison camp in unspeakable circumstances.

Karim Bangoura, former Ambassador to Washington and one of the most honorable and patriotic Africans I've ever met, was starved for eight days and then tortured with electric shocks until he signed a "confession" stating that I had recruited him for the CIA -- at a salary of $400,000 a month! Dr. Seydou Conte, former minister of education and also ambassador to Washington, managed to escape to the Ivory Coast, where he runs a medical clinic. Diallo Telli, former ambassador to the United Nations and Secretary General of the Organization of African Unity, was seized at his home in Conakry on July 18, 1975, and never seen again. When I saw Toure a year ago in New York, where he was appearing at the Council of Foreign Relations as a guest of David Rockefeller, I asked him about Diallo Telli.

"He appeared before a tribunal and was found guilty of treason," he replied.

Toure did not add what I later found out -- that Diallo Telli was starved to death in Boiro prison.

Our government chose to overlook these criminal abuses of human rights -- mistakenly, I think -- in the interest of maintaining good relations with the undisputed leader of a mineral-rich country. Last April, a few days after Toure's death, Guinea's real revolution occurred -- "real" in the sense that the avowed aim of the new military leaders is to restore freedom; Sekou Toure's much touted revolution of 1958 essentially replaced French colonial rule with a personal despotism long on rhetoric but short on measures that benefited the people, and in fact left them worse off than before independence.

Now there is reason to hope that the dark days may be finally over for Guinea's marvelously talented, artistic, warmhearted, musical and ebullient people. Toure's closest henchmen are about to go on trial, but there will be no bloodbath. The new leaders are seeking advice, not touting ideological slogans. And attention must be paid in the West to this new, inexperienced but practical-minded government; for starters, we should be prepared to give it all the economic help it can use effectively. For any country that changed its name from the People's Revolutionary Republic of Guinea to the Republic of Guinea is clearly off to a unique and refreshing start.

It's enough to make an old friend of Guinea feel like shouting, as Sekou Toure always did at the slightest pretext, "Vive la Revolution!"