THE return of d'etente between the United States and the Soviet Union has led to American impatience to involve Moscow in a wide range of negotiations, from arms control to Angola. In the 1970s, the US's urge to negotiate was premised on the value of entangling the USSR in a wide range of agreements, thereby providing it with incentives to curb its ambitions. The effort collapsed when it became apparent that Moscow did not share the US view of acceptable superpower behavior, either in regions like the Middle East, in ending the arms race, or in observing human rights.
This time around, there is added reason for acting. Soviet leader Mikhail Gorbachev is a reformer at home and has shown a startling flexibility and deftness in foreign policy. Western optimists want to help him confound his domestic cold-warrior critics; even many pessimists want the West to act quickly, lest he be overthrown before today's opportunities can be exploited.
There is no denying that the world is safer because of developments in US-Soviet relations. Mr. Gorbachev and President Reagan have sketched out a promising agenda. But experience argues for prudence in evaluating that agenda and in setting priorities.
The two superpowers - and the world - clearly have much to gain from further progress in nuclear arms control, especially at the strategic arms reduction talks (START). Details matter, just as the Soviets probably got the better part of the bargain from the Euromissile treaty signed last December. But there is shared benefit as the risks of war have declined; Washington and Moscow both emphasize the need to lower them further; and concepts like ``stability'' and ``military sufficiency'' are now common currency.
Thus there is value in talks on nuclear doctrine between the two countries' defense chiefs - first proposed to the Soviets by this author in 1981 - as well as newly agreed discussions on crisis control. Recently opened risk-reduction centers in Moscow and Washington provide instant crisis communications and are symbolically useful. Visits by Soviet and American scientists to each other's nuclear test sites increase confidence in verification, the most knotty problem in arms control. And there is merit in US-Soviet talks about chemical weapons, which also threaten mass destruction.
These remarkable developments can be supplemented by talks on global issues, like protecting the environment and stopping the spread of nuclear weapons. But while the superpowers have shared interests in reducing risks of confrontation and meeting global problems, that is not necessarily so regarding regional issues.
In Europe, the Soviets have proposed negotiations on a three-stage reduction in conventional forces. These would define current troop levels, cut half a million men on each side, and then constrain equipment most suited for offensive combat. Caution is still very much in order, however. The data exchange would merely give the Soviets credit for finally being honest about what the world has long known: that the Warsaw Pact has significant advantages over NATO forces. Even disproportionately large force cuts by the East could leave it with advantages. The test is whether the Soviets will take steps - in relatively large troop reductions and force constraints - that will offset its natural military advantage over the United States in terms of proximity to Western Europe.
In the forthcoming conventional stability talks (CST) the Soviets also want to include ``dual capable'' weapons, such as US aircraft that can carry either nuclear or conventional arms. If the West acceded, this would advance the Soviet objective of further reducing the role of nuclear weapons in NATO's strategy, to the consternation of America's allies. Thus the US should press for the early convening of the CST talks, in part as a means of regaining the initiative in East-West diplomacy; but it must still be careful in defining the agenda.
Elsewhere, superpower agreement on Afghanistan set a hopeful precedent for common interest in a diplomatic outcome. But there both sides wanted Soviet troops out and a means of regulating a longstanding competition. It is quite another thing for the US to accept the USSR as a partner in providing security for the Gulf. For months, Washington has asked Moscow for help in gaining United Nations sanctions and an arms embargo against Iran, to force it to bargain with Iraq.
Yet there has been little symmetry of interest: The Soviets would welcome a chance to increase their influence in Iran at the West's expense. The US has had to be rescued from its error by Iran's decision to accept a cease-fire in the war.
Equally puzzling is the Reagan administration's zeal to involve the Soviets in Arab-Israeli peacemaking. Jordan's King Hussein has made this a condition for talking to Israel, but there is danger of a fool's bargain. Gorbachev talks peace, but he has yet to pass a critical test: making irreversible declarations of intent on key issues. Inviting Moscow to the table before imposing this test risks giving it opportunities to gain influence without penalties if it then disrupts US peacemaking efforts.
Farther from the Middle East, where strife is endemic, it is even harder to make a case for collaborating with the USSR, except in terms clearly defined as being in the Western interest. In Central America, for instance, there is little to talk about, other than the need to limit Soviet involvement as in Nicaragua.
The US is thus right to seize the moment in critical areas where negotiating with the Soviets can secure a safer world and underscore US leadership in the Western alliance. But in that world, East-West competition continues. The West must judge wisely when to deal with the USSR and when to keep its diplomatic distance.
Robert E. Hunter is director of European studies at the Center for Strategic and International Studies in Washington, D.C.