How ironic! After thriving on decades of adversity, the North Atlantic Treaty Organization seems to be in danger of choking on the fruits of success.

But the success isn't necessarily as solid and enduring as it sometimes appears.Anyway, some serious underlying problems within NATO bubbled to the surface this week when foreign ministers from the 16-member western alliance met in Brussels to consider the organization's future.

At one point in the proceedings, France threatened to walk out. The United States used the session to complain that its allies are not doing enough to support the military buildup in the Persian Gulf. And the two-day meeting showed more signs of a continuing drift toward turning the European Common Market from a purely economic grouping into a semi-defensive alliance - an alliance that would leave the United States on the outside looking in.

If that happens, Washington could be expected to pull most, if not all, of its troops out of Europe even though such a move could make our allies needlessly and dangerously vulnerable.

Vulnerable to what? Vulnerable to the long-standing threat of Soviet aggression.

Yes, we know - with the collapse of the Soviet economy, demands for independence on the part of various republics within the USSR and the virtual demise of the Warsaw Pact or the communist version of NATO, any threat that the Kremlin could pose to Europe might seem to be a thing of the past.

But look again.

Already there's room for suspecting Moscow of cheating on the treaty curbing conventional military forces in Europe even though the ink on the pact is barely dry. Washington maintains that the Soviets have declared less military equipment than it really has in the area covered by the treaty. The Soviets are known to have transferred 60,000 tanks, armored vehicles, and artillery pieces east of the Urals before the treaty was signed; consequently, the equipment is not subject to cuts under the treaty. Other such sleight-of-hand is known to have taken place.

Even if these particular problems can be resolved, others will remain. If the Kremlin gets desperate enough, it could revert to rule by the iron hand. Or suppose that its republics somehow managed to bail out of the USSR. The surviving Russian Federation itself, with 150 million inhabitants and the largest of the 15 Soviet republics, would remain a superpower with a huge nuclear arsenal posing a potential threat to Western Europe.

The lesson should be clear: Although many weary people around the world understandably want to close the books on the Cold War, it is still too soon to do so. That means NATO must heal the growing number of cracks in the western alliance or run some needless risks to peace and security.