More than a decade has passed since the last arms control treaty was signed and ratified. That was the SALT I agreement. The hiatus is sobering. In the ten intervening years the Soviet Union and the United States have proceeded to develop new weapons systems - first MIRVs, then cruise missiles, and - soon to be - antisatellite systems in space. In short, the development of arms technology is fast outpacing the ability to control it. Small wonder that millions of people are beginning to raise their voices in protest.
While the United States government weighs its next step - and many Europeans wonder whether President Reagan is committed to arms control - the national debate at least grows more urgent and thoughtful. New approaches are being aired , not just by arm-chair dilettantes but by prominent military officers, weapons experts, and knowledgeable lawmakers. It may not be easy to pick one's way through the complexities of the issues but the public should keep informed about the broad details and thrust of some of this fresh thinking.
* Henry Kissinger, for instance, has recently refurbished the idea of abandoning MIRV-ed land-based missiles altogether and going to single-warhead, mobile missiles instead. The former secretary of state (and SALT I negotiator) argues that it is these ''multiple independently targetable reentry vehicles'' - or multiple warheads - that have destabilized the nuclear balance. Why? The SALT I treaty places limits on numbers of launchers but not warheads - the actual bombs. And so, because the number of warheads on each side far exceeds the number of launchers, the attacking side would have the advantage: It could overwhelm the opponent's fixed missile sites even though both sides had a rough balance in numbers of missiles and warheads (taking into account sea-based and air missiles as well). In Mr. Kissinger's words, ''The age of MIRVs has doomed the SALT approach.''
It is somewhat ironic that it is Mr. Kissinger who now espouses de-MIRVing of missiles, since it was he who at the time of SALT I rejected the proposal of aides to ban MIRVs. The Russians did not then have them. Well, they do now - as West Europeans who sit under the shadow of the Soviet SS-20s are well aware. But this is no reason not to consider the proposal of Mr. Kissinger - and others - to try to eliminate the disproportion between launchers and warheads by adopting a totally different system. Thus, if the US (even unilaterally) gradually phased out its MIRV-ed ICBMs and built single-warhead, mobile missiles geared to the number of Soviet warheads (not launchers), it would increase the number of US targets the Russians would have to worry about but reduce the possibility of surprise attack.
* Or take the proposal of Republican William Cohen and Democrat Sam Nunn. These members of the Senate Armed Services Committee also want to preserve strategic stability while achieving a reduction in weapons. They favor something called a ''mutual, guaranteed, nuclear arms build-down.'' If one side built a new weapon, for instance, for each new warhead added to its force it would have to eliminate two older warheads. It could modernize its nuclear force, in other words, to assure a credible deterrent but the net number of warheads would be gradually reduced.
* Still another idea espoused by some is the ''take it all to sea'' approach. The US built up its strategic forces on the basis of the ''triad'' concept - a three-legged nuclear force that includes land-based missiles (ICBMS), submarines , and bombers. This concept, argues Gen. Maxwell Taylor, former chairman of the Joint Chiefs of Staff, has blocked fresh thinking about strategic policy, led to the retention of land-based ICBMs that have become highly vulnerable, and assured a prolonged arms race. By putting its strategic forces out to sea, the argument goes, the US would be virtually invulnerable to attack.
Experts find strengths and weaknesses in these proposals. The Kissinger approach, for instance, would probably mean building new silos and violating the SALT I pact and perhaps the observed but unratified SALT II treaty. Also, if the US took this course, Moscow would be sure to follow with smaller, mobile ICBMS of its own; and, in terms of verification, it would be easier for the Russians to monitor US systems than the US theirs, because of the size of the USSR, poor weather conditions, and the closed nature of Soviet society. This would complicate arms control. Further, it would be politically harder for the US than the USSR to introduce a mobile system - Utahans or Montanans, say, might object to large numbers of missile-bearing trucks rumbling down their highways.
Beyond the merits or weaknesses of any or all such schemes, however, is the focus they put on the fundamental challenge to strategic policymakers. Can the US maintain ''superiority'' in the nuclear game (instead of ''rough equivalence'') without an even more dangerous arms race? The facts suggest not. MIRVs were not outlawed because the US had a temporary advantage; but the Russians have caught up and the nuclear balance has been destabilized as a result. Now the superpowers are into a new generation of weapons - the cruise missiles. The US has the clear advantage and is preparing to deploy some 4,000 cruise missiles on land, in the air, and at sea. These are small enough to be hard to detect and therefore, when the Russians catch up once more, the situation will become even more unstable. And what of the future - as US and Soviet military planners talk of lasers, killer weapons, and destroying each others' satellites in space?
It is dangerous shortsightedness that propels talk about achieving ''US superiority'' or waging ''a limited nuclear war.'' The lesson of history since World War II is that the Soviet Union will always, sooner or later, match any new technological breakthrough on the American side. The only realistic answer lies in maintaining a rough equivalence of strategic forces and in steady, ongoing arms control (and reduction) negotiations.
This is a moment when Mr. Reagan can show farsightedness for us all.