(FORTUNE Magazine) – Since 1979, when Ecuador's military dictatorship gave way to a democratic government, five other South American countries have shucked their generals and replaced them with elected civilian presidents: Peru in 1980, Bolivia in ) 1982, Argentina in 1983, Uruguay in 1984, and Brazil in 1985. In this happy outbreak of freedom, only Brazil has achieved substantial growth or vigor. The other five, even when they have skilled economic leaders and make the right moves, have so far been unable to break the grip of foreign debt, overblown state enterprises, and sheer bad luck. Most have brought inflation under control, but growth eludes them. Their entrepreneurial classes lack the spirit of Brazil's. Young democracies need prosperity to endure, so these five need a change of fortune soon. Often the newly elected democratic leaders are part of the problem. Adalbert Krieger-Vasena, an Argentine economist who once served as vice president of the World Bank, explains: ''The democracies have brought back many leaders of the past who are populist and nationalist, and their parties are slow to change.'' These leaders were taught to have more faith in state enterprise than in free enterprise. Still, among the six countries' leaders, only Peru's Alan Garcia, 37, remains adamantly nationalist. He took over a U.S. oil company, which wiped out any remaining interest foreign investors might have had in Peru, and pledged to devote no more than 10% of Peru's export earnings to servicing its $14-billion debt. Since assuming office at the end of 1983, Argentina's President Raul Alfonsin has turned about 180 degrees in his economic course. Having promised he would never let real wages fall, Alfonsin finally did just that when inflation reached 1,000%, and he adopted the austerities of the Austral Plan in June 1985. Price controls have cut inflation to about 60% -- not the 30% or so the government hoped for -- and government discipline has cut the deficit from 13% to 4% of the GNP. But Argentina will need a lot more than price controls to get going. The prices for such major exports as wheat and corn have fallen as much as the cost of oil. Argentine manufacturing plants are still at only 50% of capacity. Next door in Uruguay, inflation is cruising along at 60%, the economy is stagnant, and young people continue to emigrate. Bolivia, which hasn't been well organized since the Incas ran it, has achieved what one foreign diplomat regards as ''the most fascinating turnaround I have ever seen.'' When the 78- year-old Victor Paz Estenssoro came to office last year, he was faced with inflation roaring along at 24,000% a year and did something none of the other South American countries has dared. Instead of adopting controls, he simply stopped deficit spending. That brought inflation down to 20% a year. But no one wants what Bolivia makes, except for cocaine, and that was attacked recently by the U.S.-backed Operation Blast Furnace. Bolivia's inefficient tin-mining industry is sinking in a declining market. The first of the six countries to return to democracy, Ecuador, was doing fine until oil prices slumped at the end of last year. The economy was under control and growing. But the drop in oil prices means Ecuador's petroleum exports this year will be about $1 billion less than last year's $1.9 billion. The Latin American democracies find it difficult to crack the markets of the developed countries. Argentina, Brazil, and Uruguay got together recently to talk about creating their own Common Market, which might offer limited trade possibilities. But South America's new democracies will need better luck and more spirited enterprise to thrive.