THE long rule of Ahmed Sekou Toure, president and founder of Guinea, marks the evolution of black Africa. Within the history of his own reign, from the liberation of Guinea from French colonial rule in 1958 to his triumphant visit to President Reagan's Washington in 1982, there was encapsulated much of the travails of modernity on the continent.
Only a week after Mr. Toure passed on, the evolution of Guinea took another turn with a military coup yesterday. Prime Minister Lansana Beavogui, the favorite to replace Toure, was ousted in a peaceful takeover.
A poorly educated labor leader of socialist leaning, Mr. Toure played David to Gen. Charles De Gaulle's Goliath. More nationalistic and populist than many of his contemporaries in French colonial Africa, he demanded more independence than General De Gaulle, then prime minister of France, was prepared to concede. In 1958, when the other colonial possessions of France voted ''yes,'' in a referendum, Mr. Toure defiantly orchestrated a negative vote in Guinea.
General De Gaulle tossed Guinea out of the French community, ending aid and technical assistance. It was a mark more of Mr. Toure's pride and pragmatism than his Marxism that thereafter Guinea turned toward the Soviet Union.
The Soviets, as opportunistic then as they remain, obligingly supplied training, technology, and arms. United States Secretary of State John Foster Dulles and his successors worried, as well they might, about Soviet influence on then emerging Africa and on the strategic danger of Soviet bases in places like Guinea. The Soviets did take advantage, and from 1958 through much of the 1960s, and to a lesser extent into the 1970s, the Soviet Union exercised a significant role both in Guinea and in other parts of independent west Africa.
Because of his relations with the Soviet patrons and because of his close ties to Kwame Nkrumah, president of Ghana during the early 1960s, Mr. Toure was assumed by the West to be Marxist in ideological conviction and commitment. It was during those years that Mr. Toure consolidated his own grip on power within Guinea, harshly extirpating his exponents. Many were jailed, and Mr. Toure and Guinea compiled an unenviable human rights record, as so many other African nations did, throughout the relatively prosperous 1960s.
Guinea was better placed than many new nations in Africa to grow rich and provide increasingly improving standards of living for its 5 million people.
In the Guinea highlands, there were vast deposits of bauxite, iron ore, diamonds, gold, and uranium. Tourism was a possible magnet for European foreign exchange. At independence, Guinea was self-sufficient in food.
But Mr. Toure, in common with so many African leaders, squandered these opportunities. Because he accepted poor advice from the Soviets, because of mismanagement at home, because of overvalued exchange rates, because there were insufficient incentives for farmers, because of climatic misfortunes, and because trade patterns of the world changed, Guinea has never realized the promise of its early independence.
The West has reason to be disappointed with Africa, and the Africans argue that the West also bears responsibility for much that has gone wrong. However the blame should be apportioned, the point is that Mr. Toure was among those African leaders who lived long enough to acknowledge the mistakes of their formative years.
Mr. Toure, like so many others, discovered that slogans, good intentions, and nationalism were not enough to uplift their peoples. He turned away from the Soviets, in 1982 publicly embracing the US and promising an open door and full repatriation for the investments of the West. But, by so doing, he was again becoming pragmatic, not ideological.
True, the premises of scientific socialism had not worked in Africa. Thus, he moved his country back toward the middle ground of Afro-Socialism. This is his legacy and the position in the 1980s of nearly all Africa. The era of experimentation with Soviet sponsorship is largely over, and Africa will now necessarily need to blend incentive-based capitalism with the remnants in small-scale economies of state control. This may not mean that countries like Guinea will be better run, or their leaders less autocratic. But it does mean that they will take fewer economic risks and indulge in fewer flights of fiscal fancy.