Beyond the Superpower Summit Hype : History: Whether U.S.-Soviet defense cuts can restore the economic luster of the two countries will require choices no two leaders can make.

Superpower summits inevitably produce grand opportunities for the leaders of each nation. Regardless of their substance, summits permit both U.S. and Soviet Presidents to claim foreign-policy success.

The massive media attention arising from these events boosts the leaders far above their domestic critics. Both can claim that they are making the world safer, and can now divert valuable national resources from swords to plowshares. But historians of the rise and fall of nations cannot help but wonder whether the superpowers are really learning anything from history.

In arms agreements unimaginable only two years ago, both the United States and Soviet Union have been shedding the military burdens that were dragging them down like so many empires before them. Presidential staffs and advisers, not to mention strategic think tanks and analysts, are positively giddy. Instead of plans for new armaments, there is the cancellation of existing and prototype weapons. Instead of a fully blown concentration on a battle in the Fulda Gap, or off the Greenland Straits, there is a desperate attempt by the armed services to scale down and “reshape” themselves for operations in other parts of the world that (we are solemnly assured) have now become more turbulent and unpredictable.

However one assesses the likelihood and seriousness of regional conflicts, the prevailing mood among the decision-makers of both superpowers appears to be that an open U.S.-Soviet military conflict nowadays is highly implausible and that they should get on with making peace, not war.

What can have caused this swift transformation from Cold War to unprecedented detente? The simplest answer--and that favored by the political right in the United States--is that the Soviet Union “cracked.” Unable to match the American rearmament program because of its inefficient and stagnant economy, a more realistic leadership under Mikhail S. Gorbachev decided that compromise was necessary: Having failed to “win” the arms race, the Soviet Union needed to get out of it as expeditiously as possible.

While it was humiliating to concede an American victory, it was more important to concentrate resources on restructuring the Soviet economy, aided, as part of the detente “deal,” by Western credits, technology and other assistance. With restoration of the Soviet economy, however, the future of Soviet military would be an open issue. Because Moscow’s military climb-down was a coldly pragmatic decision, the argument of the right goes, the United States ought not to be lulled into a sense of false security.

A different explanation might be that policy-makers in Moscow--and even in the United States--had begun to appreciate the mutual folly of their 1980s arms race. In other words, they had begun to ponder the lessons of history.

Even when the arms race was at its height, critics pointed out that the superpowers ran the risk of hurting themselves economically and thus grow weaker in the long run. Scholars like Richard Rosecrance, in his 1986 book “The Rise of the Trading State,” observed that once again in world history, overmilitarized nations were being quietly challenged by societies that preferred commerce to conquest.

An increasing chorus of voices pointed to the irony that Japan and Germany, losers of World War II, were becoming the real “winners” of the Cold War. This message, it is becoming evident, struck home among the new thinkers surrounding Gorbachev and Eduard A. Shevardnadze. Deeply concerned about the structural weaknesses in the Soviet economy and society, eager to promote political and constitutional change before there was a full-scale collapse, and pressing for a firm check on runaway defense expenditures, Soviet intellectuals could clearly see the analogy between their country’s plight and the fate of the Hapsburg and Ottoman empires.

In such circles, “The Rise and Fall of the Great Powers” and other historically based studies are used as an argument against their own archconservatives in the military and among Russian nationalists who still want large-scale spending on armaments.

Did such a change of mood also occur in the United States? In Congress and in public opinion at large, the answer must be yes. Nothing can have been as confusing to traditional Cold War warriors during the past few years than the news that a large majority of Americans regard threats to their economic security (usually meaning Japan) as more serious than threats to their military security (usually meaning the Soviet Union).

The Democrats may have lost the 1988 presidential election on the issue of America’s military might, but much of the debate continues. Is too much being spent on armaments? How can the economy become more competitive? What is the use of being “secure” in the Indian Ocean’s sea lanes if we are not secure in our inner cities? Will the budgetary and trade deficits bring us down?

Once the summit is over, therefore, both Presidents will have to attend to their much less happy domestic fronts. In Gorbachev’s case, the problems look daunting: From the fundamental failure to get the Soviet economy working to the threatened breakup of the union itself, the difficulties are so profound that it is hard to believe that a reduction in defense spending alone would solve them. It’s difficult to imagine just how the Soviet Union, no matter how big its “peace dividend,” can compete with East Asia or a revived Europe in the 1990s.

The relative decline of the Soviet Union, no matter how successful arms- control agreements may be, is therefore most likely to continue.

The position of the United States is, as before, much more uncertain. Signs of strength mingle with signs of weakness, voices of confidence challenge the doubters and pessimists. Nonetheless, there is enough evidence--in the savings-and-loan crisis, in the plight of the inner cities and public schools, in the decomposition of the domestic automobile industry, in the ability of vested interests to block structural reforms--to suggest that the struggle to remain competitive with Europe and Asia over the longer term, and thus to preserve the American position in world affairs, will be hard, unrelenting and not very easy to measure.

But that also has historical precedents, since many of the great powers of the past, such as Britain, did not collapse dramatically and suddenly, but instead faded away as imperial powers, decade after decade, generation after generation.

Whether Bush and Gorbachev have really learned those lessons cannot be proved by a summit, with all of its bonhomie and media hype and public pronouncements. It will be proved in the efforts that the two administrations devote to persuading their peoples to take seriously the challenge to both the Soviet and the American position in world affairs by the rising commercial powers.

That implies unpopular choices on the domestic front, as well as popular proposals on arms reduction. Because of that, it will be some years yet before the historian can judge whether Soviet and American efforts in the 1990s to control defense costs and improve economic competitiveness do succeed in reversing the course of decline.