When Defense Secretary Caspar Weinberger revealed the existence of Soviet nuclear weapon storage sites in Eastern Europe last month, he inadvertently raised a larger issue. In response to press questions as to whether the weapons being stockpiled--short-range or "tactical" nuclear systems--were being discussed in any continuing arms control negotiations, he equivocated. This is because they are not being discussed.

The omission of tactical nuclear weapons --nuclear-tipped artillery shells, surface-to- surface rockets and land mines--from the Reagan administration's arms control agenda is ironic because the longstanding NATO advantage in nuclear delivery systems of less than 1,000-kilometer range is fast eroding. If one excludes the systems with the shortest range--i.e., the nuclear artillery tubes--from the calculation, one counts some 409 launchers for NATO to some 630 for the Warsaw Pact outside the Soviet Union.

In the warhead totals of both sides, tactical weapons represent the largest single category. They are also the most dangerous, because if war breaks out, they are the most likely to be used. They should be placed on the bargaining table as soon as possible.

NATO's short-range systems are located in Belgium, the Netherlands, West Germany, Italy, Greece and Turkey; France has short-range launchers of its own. Warsaw Pact launchers are located on the territories of East Germany, Poland, Bulgaria, Czechoslovakia, Romania and Hungary, as well as on Soviet territory.

NATO originally deployed short-range or tactical nuclear systems because their very presence complicates an attacker's problems. Their deployment makes massing armor for attack difficult. The Soviets presumably deployed their short-range systems for similar reasons and for the support of their offensive doctrine.

But regardless of why these nuclear weapons were deployed, few would argue that they are necessary in their present numbers. The United States implicitly accepted this point by unilaterally withdrawing 1,000 nuclear warheads from Europe in 1980.

Many of the tactical nuclear weapons in Europe are useless. For example, the United States stored hundreds of nuclear land mines in Europe in the 1950s. They are still there. They have never been deployed. This is because the Germans would not permit it.

One suspects it is a bad idea to allow the first vehicle that crosses an arbitrary line to risk starting global war. Furthermore, aircraft on nuclear alert could have more useful conventional roles, as could the troops that guard nuclear storage sites. By eliminating nuclear roles for some of its dual-capable weapons, NATO gains forces that can fight, at the expense of forces that can only posture.

The Supreme Allied Commander, Gen. Bernard Rogers, has suggested that NATO defense deemphasize tactical nuclear weapons. He points out that modern military technology has effective and safer substitutes for them as tank killers, for example, and he has repeatedly urged that NATO acquire these new technologies. Is anyone listening?

In brief, although it might be dangerous to denuclearize the NATO forward area completely, there is no good reason why NATO could not thin out its tactical nuclear forces to advantage, provided that it persuades the Russians to do the same.

Fortunately, the arms control forum for reducing tactical nuclear weapons on both sides already exists. It is the 10-year-old negotiation on mutual and balanced force reductions (MBFR) in Central Europe. The countries participating in these negotiations happen to be those with short-range nuclear weapons on their soil.

Because of their glacier-like pace, the MBFR talks have largely disappeared from public discussion. Yet agreement may be closer in that forum than in any of the other ongoing arms control negotiations. President Reagan refers to these talks as "conventional arms talks," although there are no arms, only personnel, being considered for reduction, at present.

Yet until 1979, short-range nuclear weapons were being negotiated in MBFR. NATO had hoped to trade away some of its nuclear weapons against Warsaw Pact tanks. With the increase in the numbers of Warsaw Pact tactical missiles in the area covered by the MBFR negotiations, the next effort should be to limit tactical nuclear weapons on both sides.

An agreement restricting tactical or short-range nuclear weapons in Europe would add much to the value of the INF or theater missile talks. It could ensure that neither side makes up with even more dangerous short-range weapons what it loses in intermediate-range capabilities. That in itself would be worth the effort.