The Fulbright program: it's a bargain

''What have been the greatest successes and failures of United States foreign policy since World War I?'' This was the question I put to a score of leading historians associated with the Woodrow Wilson Center at Washington's Smithsonian Institution. Their answers have profound importance for American policy today.

The two initiatives which they judged most successful were relatively low-cost and depended on persuasion, not coercion - the Marshall Plan and the Fulbright-Hays educational exchanges. Both success stories were cooperative, depending upon a mutuality of planning, contributions, and shared benefits. In just three years, 1948-1951, the Marshall Plan helped Europeans to the economic recovery and political stability that makes them prosperous trading partners and basically sound allies in an Atlantic community.

The Fulbright program also grew out of World War II. It was financed initially by funds owed by other countries to the US for wartime aid. Once these debts were settled, Washington and other governments put up funds from current accounts. Still, the US burden for the next fiscal year was budgeted at a mere $ 48.1 million - two or three times the entire school budget for a small town such as Lexington, Massachusetts.

The Reagan administration, however, has asked Congress to cut these outlays to $22.5 million, a reduction that would pare the exchange of graduate students and professors with 120 countries to 59, ending most programs in the third world.

Does this matter? Why did the Wilson Center scholars think the Fulbright exchanges are so useful? What do Americans get (and give) in these programs?

My answer comes in part from a year as Fulbright lecturer at the Institute of International Relations, University of the West Indies in Trinidad, 1977-1978.

What did the US gain? My views differ on many topics from official US policy, but future diplomats and educators from a dozen Caribbean islands got to know one American's perspective on world politics, particularly on US-Soviet relations. They learned how seriously many Americans regard the issues of nuclear war and global interdependence. They were guided to books and articles far from their usual fare. They and I learned we could disagree on many points and still be friends. My own writings in Trinidad newspapers and the Caribbean Yearbook of International Relations meant that I could reach audiences beyond the university and the elementary and high schools I visited.

And what did I learn? Perhaps more than my students. I came to understand the outrage that permeates third world sensibilities and the reasons for it. Living in a fishing village I also saw the joys and anxieties of common folk struggling to improve their lot. I also became colorblind.

The local fisherman would say, ''Hey pro (prof), sit down and teach me something.'' There wasn't much useful I could teach fishermen, but I did lead their children into finger-painting (materials supplied by UNESCO) and into making murals to brighten local hospitals. We also talked about the ''crab syndrome'' - pulling each other down - that impedes island development.

My own education in Trinidad and Tobago was something money could not buy, but it is passed on each year to students in the US. Not only do they hear about human encounters but also about the books and authors I came to know in Trinidad - works by the country's late Prime Minister, Eric Williams, perhaps the leading scholar among the world's recent statesmen, and V. S. Naipaul, the Trinidad-born novelist whom many judge to be one of the greatest living writers. As my students meet these authors, they are broadened as I was.

What of the cost? My salary was paid by the US State Department, at levels below what Trinidad professors earn or what I receive here. My housing was paid by the institute. I had to pay hundreds of dollars to ship my books. Still, I got by quite well by not having a car and by eating the fruits of the sea and my garden.

Was my experience unique? Not at all. Many other Fulbrighters have had similar, perhaps even more rewarding experiences.

Many of the best things in life can be free - or at least low cost. As President Derek Bok of Harvard has put it, there is no better investment ''dollar for dollar'' than the exchange of scholars. Let's not cut them off for the cost of half a tail fin on a new missile.