When Treasury Secretary Nicholas F. Brady unveiled a new U.S. strategy in March 1989 to reduce some of the huge debt Third World nations owed to commercial banks, his aides listed 39 nations that might be eligible for help.

Brady's was a revolutionary idea, compared with the idea that had preceded it. Brady contemplated actual debt relief or forgiveness, financed by about $30 billion put up by the World Bank, the International Monetary Fund and Japan.

The old strategy, the Baker Plan, called for new loans on top of the old ones. That practice simply helped debtor nations pay off interest obligations, while preserving the fiction that the banks' loans were still productive. Write-offs force the banks to acknowledge real losses.

Nineteen months after the inception of the Brady Plan, however, the great majority of poor countries are still overwhelmed by massive commercial debt, their economies laid to waste by high unemployment and negative per-capita growth induced by failure to control their exploding populations. The biggest single act on the debt-relief front was a diplomatic gesture arising out of the Persian Gulf crisis: American forgiveness of $7 billion owed by Egypt (which wasn't being paid anyway).

The Brady Plan, at $30 billion, is under-funded. But in today's capital-short global economy, it's hard to believe that additional funds for debt relief can be found. Meanwhile, the flow of regular loans has been reduced to a trickle, in part because the borrowing countries have largely quit making payments to the banks -- and because some banks, especially in America, are going through hard times.

Brady Plan agreements have been reached for only three countries -- Mexico, Costa Rica and the Philippines. And of these, only Costa Rica obtained significant debt relief. Only two more are in any stage of prospective negotiations -- Venezuela and Morocco. As Peter Hakim of the Inter-American Dialogue points out, a rise of 1 to 2 percentage points in international interest rates could wipe out all of the benefits to date.

What's happened to the rest of the 39 countries that were supposed to be involved in the Brady Plan? They haven't met the economic-reform tests required for help. At least 15 of the 20 big Latin American debtors, including Brazil and Argentina, are behind in their payments to commercial banks. But as they see it, being in arrears gives them more relief than they could get through a Brady Plan agreement.

A key gap in the Brady Plan strategy is its focus on so-called "middle income" countries whose debts were primarily with commercial banks. It did nothing for poorer countries, in Africa and elsewhere, most of whose loans had been government-to- government.

"If debt reduction was a good idea, it was a good idea for reducing all debt, including official debt," said Sir Jeremy Morse of Lloyds Bank. President Bush responded with an "Initiative for the Americas" that could lead to cancelation of some U.S. government loans to Latin countries. And at the recent IMF-World Bank meeting, several proposals, notably by Britain and the Netherlands, were made to forgive other bilateral loans.

The real problem is that the drop in private lending has resulted in "officialization" of thedebt. At the start of the debt crisis in 1982, less than 40 percent was held by official creditors. Now, it's grown to about 50 percent. More of the burden is being placed on the IMF and World Bank at the very time concern is growing that they may have already become overextended by their loan and debt-relief operations.

Yet, given the fragility of American banks as the United States enters what could be a major recession, the reliance on official lending is likely to grow.

Already, many private bankers think they detect an easing of what they considered the hostility of the Bush administration when it came into office in January 1989. They cite a new, supportive attitude of Treasury Undersecretary David C. Mulford on their complaint that debtor nations that reduce arrears to commercial banks shouldn't get new loans from the IMF and World Bank.

Adding it up, the Brady Plan, for all the praise routinely heaped on it in communique's from the Group of Seven industrial nations and IMF-World Bank reports, seems to be stalling out. The Economic Commission for Latin America and the Caribbean makes the point that "the factor which has had the greatest {positive} impact this year" has been the Persian Gulf-inspired run-up in oil prices. That's been a bigger help to Mexico and Venezuela than anything offered by the Brady Plan.

Conversely, the debt problem will be exacerbated for all the countries that import oil. After much fruitless debate at the recent World Bank-IMF meeting, no one had any new answers.