We should be alert but not panicky, I think, about the world credit crisis. The figures are astronomical. Robert Solomon, writing calmly for the Center for National Policy here, estimates that the long-term external debt of the non-oil developing countries is around $505.2 billion. That's external debt, mind you; money owed outside the country. If there's trouble, says Mr. Solomon guardedly, it's apt to involve one or more of three countries, Argentina, Brazil, and Mexico.
Mexico, as you are aware, is now in default on external payments. The layman finds this vocabulary tricky. As John Kenneth Galbraith observes in the current Atlantic Monthly, banks no longer have bad debts: ''In the greatly improved language of our time, they have only nonperforming loans.'' Mexico had loans like that, and external debt amounted to $58.1 billion as of March 1982. Argentina had $40 billion; Brazil $58 billion.
Mr. Solomon seems to be saying that the situation in some cases has passed beyond the capacity of individual banks or even nations to handle and that now it's time for the world financial firefighting apparatus to stand by - the International Monetary Fund in particular. Domestic reorganization in threatened countries, Mexico for example, is ''imperative,'' of course, Mr. Solomon says, but it goes beyond that. ''At the end of 1981,'' he says, ''the nine largest American banks had issues outstanding to Argentina, Brazil, and Mexico equal, respectively, to 20, 42, and 45 percent of their capital.'' Forty-five percent of their capital? Whew, that's a lot of money!
Mr. Solomon is quite calm about it. He comments that, ''if one wanted to imagine a banking crisis, one could conjecture that Argentina, Brazil, and Mexico all go into default on their bank debt. This would throw the largest American banks into insolvency.'' Yes, it certainly would, and Mr. Solomon adds that ''even rumors of default'' could help cause a liquidity crisis. This development, he hastily adds, is ''highly unlikely.'' Still, it's there, and the international firefighting brigade had better have its pressure up and its nozzles pointed. Mr. Solomon notes, comfortingly, that the world credit community is aware of the situation; yes, ''the US government showed its readiness to help when it quickly made $2 billion available to Mexico in August.'' Also, he adds, ''the Federal Reserve can be assumed to be prepared to carry out its central banking function of lending to banks facing a liquidity drain based on fear.''
There's a parallel problem, too, Mr. Solomon explains, in world trade. What if commercial banks outside the debtor countries should sharply curtail their lending to the developing world? This would be serious. ''The result could be a drastic contraction in the economies of the debt-dependent countries, accompanied by steep reductions in their imports,'' Mr. Solomon says. A self-perpetuating chain of curtailed credit would aggravate recession. Indeed, says Mr. Solomon, quietly, ''this process has already started.''
Unemployment in the industrial world is now 30 million and rising. Men like Mr. Solomon don't want to make the bankers jittery and, fortunately, the man in the street doesn't read the financial pages. But the situation is one to watch. ''A thousand banks from all over the world '' are involved in loans to Mexico, he notes. What would he do? Why, he says, the International Monetary Fund should be (and doubtless is) ready for emergencies. It should be prepared to stand by and douse the fire if it starts. It has sufficient resources at the moment, he says, but it wouldn't hurt if Congress voted more. And if aid isn't available? Mr. Solomon doesn't raise his voice or use superlatives. He just observes that if the international fire brigade isn't ready, ''We could witness economic and conceivably political chaos in the debtor countries, with inevitable harmful effects on the United States and the rest of the world.''