The persistent debt problem of the world's less-developed countries (LDCs) will not go away. Alan Greenspan, who heads up the consulting firm of Townsend-Greenspan & Co., says the next 90 days are critical because of the stresses on the banking system and on third-world economies.
William Cline, a senior fellow at the Institute for International Economics (IIE) in Washington, D.C., agrees. He notes that there is still ''substantial risk'' even though the International Monetary Fund (IMF) has now given the ''superdebtors'' - nations that have more than $200 billion in debts - some breathing space.
And Sen. Charles McC. Mathias Jr. (R) of Maryland, chairman of the Senate subcommittee on international economic policy, noted last week, ''The dilemma we face is not just an economic one, but also one of general confidence in our financial system.''
Although there are countless variations on what might develop, economic and academic experts often break down projections into two broad scenarios, though the second is considered far less likely to occur.
* In the first scenario, the US economy starts to pick up steam. As the US locomotive hurtles along, it pulls the economies of the developing countries with it as Americans start to buy imported goods. The once-spendthrift nations, with a little help from the IMF, the US government, and the Bank for International Settlements, make their peace with the banks. There is enough money available in the system to pay for new combines in the farm belt, automobiles from Detroit, and new factories in Des Moines.
* In the second scenario, the price of oil collapses. For Mexico's already precarious economy, there would be no more tomorrows. At the same time, things go from bad to worse in Brazil and Argentina. These three ''superdebtors'' have used up the money they have borrowed just to meet day-to-day expenses. Their creditors, the nine largest US banks, are finally forced to declare the loans bad. They write off some $14 billion, representing one year's principal and interest. Set against some $5 billion in profits, the banks end up wiping some $ 9 billion in capital off their balance sheets over a period of years. The Fed steps in and quickly reflates the economy to try to salvage the situation. The US economic recovery that was under way gets snuffed out.
It is still considered too early to discount completely either of these situations - or any of their countless variations. But some middle version is considered most likely.
In interviews with economists, bankers, and academic experts, it becomes clear that there is considerable disagreement over what the future holds. Even the apparent agreement reached last week by the Group of Ten, the major industrial powers, to enlarge the resources of the IMF is not viewed as a long-term solution to the problem. Peter B. Kenen, professor of economics and international finance at Princeton University, says the debtor countries still must meet the IMF's conditions and turn around their current-accounts problems, which are caused by having too many imports and too few exports.
David Banks, senior vice-president at Chase Manhattan Bank, points out that often, the need for cash can be self-defeating. Mexico, for example, is so desperate for foreign exchange that it needs to pump as much oil as it can sell. But because this puts more oil on the international market, it contributes to oil's falling price - which hurts the Mexicans.
Economists agree that the problem is immense. The ''superdebtors'' have accumulated debts of $216 billion. Because of cash-flow problems, last year they deferred making payments on the principal. Late in the year they also stopped making interest payments and instead borrowed more money just to pay the interest on the debts that were coming due.
In this high-wire act, the IMF has played a central role, acting as a safety net. As Felix G. Rohatyn, senior partner at Lazard Freres & Co., noted in his testimony before Senator Mathias's subcommittee Jan. 19, ''It is clear that for the time being, a significantly beefed-up IMF, together with bank loan rescheduling, is needed to continue to avoid a crisis. Unless a strong worldwide recovery were to occur soon, which seems unlikely, the potential for social and political radicalization will become greater and greater.''
The IIE's Mr. Cline, who unveiled the second scenario for Mr. Mathias's subcommittee, believes it is an ''unlikely . . . but not an impossible one.'' If the banks were unwilling to continue to lend money to the debtor nations - which is essential to keep them afloat - it could cause major ripples in the US.
For example, if the banks were to write off a significant portion of their LDC debt, he says, they would have to reduce their loan portfolios to keep the ratio of their loans to capital intact. He figures the bankers would lop off $ 150 billion in loans, the great bulk of it to US industry. Such a move would be catastrophic to the economy, but Cline maintains that ''those are the stakes.'' In part because of that concern, the price of gold has moved up $100 per troy ounce in the last few months.
Mr. Kenen says there is now a 5 percent possibility the world's economic system will become unglued. He says he is not very optimistic about the outlook for the debtor countries. For example, he does not believe the countries borrowing from the IMF will be able to meet the IMF's terms and conditions for lending them billions. This will raise the question of whether or not the IMF will cut off credit to the countries. He says he also doesn't believe they will be able to solve their current-accounts problems, since they will continue to import more than they export.
Bankers, however, don't agree that things are so black and white.
One well-respected bank economist who wishes to remain anonymous says that even though the debtor countries won't meet their targets precisely, ''they will do better.'' That progress, he maintains, ''will earn them the respect of the international community.'' When a problem is so conspicuous, he maintains, ''it is not the thing to worry about.''
The bankers who are lending the money say that even though there is still room for a lot of concern, the situation is not as dire as it was. David Lovejoy , senior vice-president and treasurer of Security Pacific Bank, says he feels the support the LDCs have received from the IMF and the US ''is a great comfort to us.'' And, in large measure because of this support, he says it is likely the bank will continue to lend money to the debtor nations.
Chase Manhattan's Mr. Banks likewise says he does not believe the situation will end up as a great ''holocaust.'' He adds, ''We have not lost any money lending to the Mexican government.'' But he quickly adds, ''There is no question banks will be a lot more discriminate about whom they lend to in the future.''