In spite of an Argentine mini-coup that threatened to mar his trip, President Bush has begun a weeklong swing through South America to promote his "Enterprise for the Americas" initiative.

First announced in June, the plan emphasizes free trade, increased foreign investment and debt restructuring to promote economic and political stability in the Western hemisphere.That's a large order and is the latest in presidential programs aimed at improving life in Latin America. Such plans, some with grandiose names, have been promoted in every previous administration - with varying degress of limited success.

Bush has high hopes for the initiative. He wants a hemisphere-wide free-trade zone stretching from Canada to the southern tip of South America. Such a trading pact would be larger than a United Europe or the Asian trading blocs and would be more efficient and competitive.

Thus far, Bush's plan has received strong support from the South American governments, the business community and in public opinion polls.

With the road to economic reform still strewn with obstacles, part of Bush's mission will be to sell the people of South America on the argument that short-term sacrifice can produce long-term benefits.

At a time when many of these leaders have been getting resistance from their own countrymen, Bush may not necessarily impress the people of South America. But it's worth a try.

The first four countries on Bush's itinerary - Brazil, Uruguay, Argentina and Chile - all were under military rule within the last few years and now have elected governments. The fifth country, Venezuela, has been democratic since 1958.

The president hopes to discuss how to safeguard democracy and political stability in a Latin America still in transition from authoritarian regimes to democratic ones.

Economic chaos or leftist-led political turmoil could again usher in military rule. The military turmoil in Argentina even as the president travels is unsettling, though officials have downplayed its importance.

The first time Bush visited South America in February he met with the leaders of Bolivia, Colombia and Peru to discuss the war on drugs. This time, he will explore additional anti-drug efforts with other key leaders in the region. Since the drug traffic has recently expanded into the countries on Bush's itinerary, the timing is significant.

If the president's trip is successful it might lead to closing of a depressing chapter on U.S.-Latin American relations dominated by nationalism, suspicion, and misunderstanding - and open a new era governed by mutual respect and cooperation.

There are no guarantees. But the president's journey is a hopeful encouragement of stronger democracies and more stable economic environment.