MOSCOW, SEPT. 2 -- When Soviet leader Mikhail Gorbachev meets with President Bush in Helsinki next Sunday, his chief aims will include preventing the Persian Gulf crisis from escalating into armed conflict near the Soviet southern flank and winning assurances that the United States has no long-term controlling ambitions in the gulf region.

Despite an unprecedented show of unity with Washington in condemning Iraq's invasion of Kuwait, Soviet officials throughout the government and armed forces are deeply concerned that the accelerating U.S. military buildup in the gulf will diminish chances for a political settlement and create new strains on Moscow's relationship with the West.

Gen. Vladimir Lobov, commander of the Soviet-led Warsaw Pact military alliance, said recently that the continued presence of tens of thousands of U.S. troops 700 miles from the Soviet Transcaucasus threatens the strategic balance of power and even the continuing negotiations in Vienna on cutting conventional arms.

The level of anxiety here about American intentions is acute. Today, the Communist Party newspaper Pravda -- still the best reflection of Kremlin thinking -- published a highly skeptical commentary on the U.S. buildup that assessed the chances of a political settlement at "only 50-50" now and expressed grave concern about the effect of a "military solution" on the future of superpower relations.

In the event of armed conflict, the article asserted, "the victims would not only be human beings and oil refineries, but something that at first glance may seem ephemeral, yet is all the same extremely important -- the dawning process of humanizing relations between East and West, international life as a whole and the process of detente."

The commentator, political analyst Gennadi Vasiliyev, declared also that the U.S. military presence in the gulf was not merely for the altruistic reason of protecting an ally but "above all, for the oil . . . and the strengthening and widening of American military presence in the region." As corroboration, Vasiliyev cited Western press accounts putting forth the same viewpoint.

So far, Gorbachev's public comments on the U.S. buildup could be taken as criticism only in the most oblique sense. At a news conference Friday, he said that the sooner U.S. troops left the region "the calmer we all will feel." Time and again he emphasized the need for a political settlement and for an "Arab solution."

Even without direct involvement, the economic cost of the gulf crisis for the Soviet Union has been high, with losses in trade already amounting to nearly $900 million. As a country in an economic depression marked by food rationing, a thriving black market and the potential for social disorder, the Soviet Union is in no mood for expensive international engagements, especially not after its own disastrous war in Afghanistan.

According to a recent poll here, Soviet citizens with an opinion on the matter said they approved of Gorbachev's handling of the gulf issue by a ratio of 3 to 1. But if the price of unanimity with the United States were to increase, either financially or militarily, that support would almost surely evaporate.

In fact, Soviet domestic problems are so pervasive, affecting the daily lives of every citizen on the most basic levels, that the vast majority of the populace seems to have grown fervently isolationist. When East European countries began breaking free of Moscow, nearly everyone here -- with the exception of the upper echelons of the army -- seemed gratified to be relieved of the burdens of empire. And when it became clear that the two Germanys would reunify, even veterans with vivid memories of German depredations in World War II made little protest.

Gorbachev's foreign policy of "New Thinking" is based on a need to strip away the illusions of the past and concentrate on rebuilding a collapsing society, even if the price is paid in the currency of geopolitical advantage. "The Soviet Union," wrote political columnist Andrei Kortunov in the newspaper Moscow News recently, "has already ceased to be a superpower." If that is true, most people here are relieved.

But even if it has become a profoundly inward-looking nation, the Soviet Union is not without influence. With its military power and the international authority of Gorbachev, it still has enormous influence -- especially with Iraq, the recipient of Soviet arms for three decades.

Soviet Foreign Minister Eduard Shevardnadze has resisted the arguments of military men and Arabists in his own bureaucracy who are reluctant to criticize an old ally and who embrace a post-Cold War policy in the Middle East and gulf region. During a session here last month with an Iraqi envoy, Shevardnadze reportedly refused to soften the Soviet Union's condemnation of the invasion of Kuwait; he agreed to keep the lines of communications open with Iraq, but went no further.

But in the month since Shevardnadze and Secretary of State James A. Baker III issued a joint statement condemning Iraq, subtle fissures have appeared in the partnership. Foreign Ministry spokesman Gennadi Gerasimov chided Washington for expelling 35 Iraqi diplomats, and some U.S. officials have wondered aloud why Moscow still has 200 military advisers in Iraq. More recently, Soviet Deputy Foreign Minister Alexander Belonogov asked publicly why Washington has not given a guarantee that it will withdraw from Saudi Arabia in the event of a political settlement to the crisis.

Next Sunday's Bush-Gorbachev meeting "comes at a good time," said a senior Arab diplomat. "Even if there are tactical differences between Washington and Moscow, there is a common goal -- an Iraqi withdrawal from Kuwait. And that kind of show of unity in Helsinki could have a very sobering effect on Saddam Hussein. The question then is this: Does Saddam Hussein care?"