The designation this summer of $465 million in U.S. aid to combat drug trafficking in Mexico and Central America -- along with the valuable cross-border dialogue that helped bring about this Merida Initiative -- is a step in the right direction. With certain notable exceptions, the United States has largely ignored its southern neighbors, and signs of new cooperation are welcome.

But given the urgency of the problems we face, this step is disappointingly small. A long road lies ahead. We in the Americas have an unprecedented opportunity to create a better, safer hemisphere, but only if each country contributes all that it can. It is high time for the United States to redefine its approach to regional aid, not merely in the name of friendship but also in its own interest.

The Merida Initiative is stingy by any standard but especially by U.S. standards. Central America, Haiti and the Dominican Republic are allocated only $65 million -- one-sixth the amount that legislators initially deemed necessary. Mexico receives $400 million a year, a comparatively princely sum but the same amount that the United States spends in Iraq in a single day. With such expensive enemies, there is apparently little room for friends.

A government, of course, is free to allocate its funds as it sees fit, especially where foreign aid is concerned. Yet support for the war on drugs is an investment in a shared problem, one that is largely fed by the enormous demand for drugs in the United States. Fighting drug traffickers is not only a Latin American responsibility, it is also an American responsibility, in the hemispheric sense, and the Merida package only begins to fulfill the United States' share.

The amount of money is part of the issue. The choice of areas to fund is more important. The foremost responsibility of national leaders is to protect their citizens. To this end, the United States must broaden its definition of national security. Like all developed nations, it must confront the fact that no country can be safe while poverty, illiteracy, violence, preventable diseases and environmental destruction wreak havoc on others. Any foreign policy that views these issues as someone else's problems is doomed.

The primary U.S. concerns regarding Latin America are drugs and illegal immigration. Yet these are symptoms, not diseases. The disease itself, the cause of these visible effects, is poverty in the Western Hemisphere's developing nations. It is poverty that creates fertile ground for drug trafficking. It is poverty that sends so many legal and illegal immigrants over U.S. borders. Poverty needs no passport to travel and cannot be detained by walls.

This disease could be countered by investing in education, the only tool that can lift Latin Americans out of poverty for good. The United States could make a tremendous difference by making education a priority. According to recent estimates, the country is spending $3 million per mile to build a fence along its border with Mexico designed to keep out illegal immigrants seeking opportunities they cannot find at home. But for every mile of that fence, 2,500 young Latin Americans could receive monthly $100 grants to cover the costs of staying in school so they can get good jobs. For every mile of that fence, 15,000 children could receive Internet-capable laptop computers from MIT's Media Lab, enabling them to join the globalized world rather than falling behind. The possibilities go on and on.

These are the investments that could keep Latin Americans from risking their lives to enter the United States anyway they can. These investments would be good for all our countries.

These are exciting times in the Americas. The United States has new leadership on the horizon and a chance to reexamine its foreign policy. Latin America has never been more democratic or better equipped to spend aid money effectively and transparently. If the United States were to extend its generosity to us, I am confident that the results would be extraordinary. After all, a more prosperous Latin America benefits not only its own people but the United States' as well.

The writer, who won the Nobel Peace Prize in 1987, is serving his second term as president of Costa Rica.

(Aug. 17, 2008)