FOR SOME years Venezuela, a working democ racy, a longtime good friend and a country whose oil lets it pay cash, has wanted to modernize its air force. Not that there was any particular new threat to tend to or new national ambition to serve. But the idea of being ready to defend one's oil fields is current. Venezuela has come to see itself as a country with regional responsibilities in an area of growing turbulence. Its eye fell on the American export models designed for Third World air forces that can uulse good planes but don't need the hottest aircraft in the U.S. inventory.

What happened then is that the Reagan administration came to power and enunciated a new arms transfer policy, one tending to shift the presumption of correctness from those opposed to a sale to those favoring one. At the same time, according to suggestions made in congressional hearings last July, the U.S. Air Force whispered sweet inducements into Venezuela's ear. Shortly after, Venezuela put in for two dozen F16s, world-class fighters that the United States and its NATO allies are putting into their own air forces as fast as they come off the line.

So, you might say, F16As may be a little gaudy for a country in Venezuela's still generally calm military circumstances. But no non-NATO country that has bought this plane (Israel) or been promised it (Pakistan) is likely to get into less trouble, or to be able to afford the half-billion- dollar cost more. If a reliable democratic friend like Venezuela can't be entrusted with the F16, who can? Anyway, the Nixon-Ford-Carter go- slow-on-hot-planes policy merely gave the West Europeans, and even the Soviets, entry to the Latin market. This time Venezuela was eyeing the French Mirage 50.

But, unfortunately, that's not all. The F16A is a big step up from any plane currently in a Latin air force. It is the prestige plane, the one most calculated to expand local air force chests and to confer the aura of American favor. Its acquisition by one Latin air force will almost certainly whet the appetites of others, and may incline Cuba to try to match it. Having