HO CHI MINH CITY, VIETNAM, SEPT. 8 -- When Soviet President Mikhail Gorbachev launched an Asian initiative five years ago aimed at expanding Moscow's influence in the region, the move sent tremors through many of the area's capitals.

Coming on top of the Soviets' buildup of their Pacific Fleet and military presence at Vietnam's Cam Ranh Bay, Gorbachev's overtures to Asia in a July 1986 speech in Vladivostok seemed to herald increased superpower competition in the economically booming region. Such was Vietnam's dependence on Moscow and its role in advancing Soviet interests that some U.S. strategists by then were describing the country as "the Cuba of Southeast Asia."

Today the Soviet military presence in Vietnam is little more than an empty shell, and Vietnamese officials are talking of turning Cam Ranh Bay into a commercial facility or tourist resort.

The decline of Cam Ranh Bay, once Moscow's largest forward-deployment naval base outside the Soviet Union, has been underway for some time. But the collapse of communism and dismemberment of the union after last month's failed coup attempt against Gorbachev seem to have sealed the base's fate.

The Soviet withdrawal from Cam Ranh Bay mirrors a decline in economic relations with Vietnam. Soviet aid to the country already had been slashed well before the coup attempt, but now there are questions as to whether remaining trade and economic cooperation agreements will be honored, and the Vietnamese are scrambling to find new markets for goods previously sold almost exclusively to the Soviet Union and Eastern Europe.

As Vietnam's relations with China deteriorated in the late 1970s, Hanoi signed a 25-year Treaty of Friendship and Cooperation with Moscow in November 1978 and soon welcomed the Soviet navy to Cam Ranh Bay. One of the world's finest natural harbors, the bay had been developed as a naval base by the United States during the Vietnam War.

By 1985, the Soviets had significantly expanded the base, installing communications and electronic intelligence-gathering gear, missile-loading equipment, expanded fuel-storage capacity and base facilities for at least 38 reconnaissance, anti-submarine warfare and strike aircraft, as well as about 25 ships, including four to six attack and cruise-missile submarines. The buildup in Vietnam, combined with a doubling of the Soviet Pacific Fleet in 20 years to more than 800 ships -- making it the largest of the country's four fleets -- helped Moscow inject power into the Asia-Pacific region and sent jitters through its pro-Western states.

By 1989, however, the Soviet posture in the Pacific no longer appeared so threatening. According to the Honolulu-based U.S. Pacific Command, the Soviets stopped sending Tu-95 "Bear" attack planes toward Alaska on simulated bombing runs and began pulling most of their aircraft out of Cam Ranh Bay. A squadron of at least 14 MiG-23 jets was withdrawn, along with some 16 Tu-16 "Badger" medium-range bombers.

Now, according to diplomats and Vietnamese officials, only a handful of Soviet ships and planes are left at the base.

Questions about the base's future came up in June when a Soviet admiral, Vladimir Kasatkin, said Soviet forces would continue to use Cam Ranh Bay to support naval operations in the region. He was contradicted by the Soviet Embassy in Hanoi, which said a pullout would be completed by 1994.

Some Vietnamese officials now believe the Soviets should leave sooner so that the site can be developed as a ship-repair facility or a hub for tourism, said a ranking government official who cited the bay's smooth waters and nearby unspoiled beaches.

"It's a pretty place. They can turn it into a Club Med," said a European diplomat, not entirely in jest.

While Vietnamese officials tend to play down the impact of the dramatic changes in the Soviet Union, they clearly have been shocked by the transformation of their communist ally and patron. Some Vietnamese Communist Party hard-liners convey a sense of betrayal as they vow to avoid the "mistakes" of their former Eastern Bloc comrades.

Soviet aid to Vietnam totaled about $10 billion from 1986 through 1990, according to government economist Le Dang Doanh, but then it was cut back sharply. Now the aid has virtually ceased, and a $1 billion two-way trade agreement between the two governments is considered a dead letter. The Vietnamese government hopes, however, that three trade accords signed earlier this year with individual republics still will be honored. The largest of them is a $300 million barter trade agreement with the Russian republic.

"It's difficult for our economy, but not as serious as we thought," economist Do Duc Dinh said of the Soviet upheaval. He said the blow has been cushioned by Vietnam's acquisition of new trading partners and increasing offshore oil production by a Soviet-Vietnamese venture. This year, Japan is expected to replace the Soviet Union as Vietnam's top trading partner, despite nominal Japanese adherence to a U.S. economic embargo, and oil production is projected to reach 4 million tons, exceeding the country's consumption.

A major problem is that hundreds of thousands of jobs depend on garment and textile exports to Eastern Europe and the Soviet Union. Unless Vietnam finds new markets, factory closings risk aggravating already severe unemployment.

Another dilemma is where to send the thousands of students and trainees regularly dispatched to Soviet schools.

"In the long run, it's a good thing," a Vietnamese official said bitterly of a sharp decline in Soviet scholarships. "We've been sending thousands of students to the Soviet Union, but they can't do anything to help the Vietnamese economy. The backward technology and knowledge they get from Soviet Union is only suitable for the Stalinist economic model."

After commenting in an interview that the Vietnamese "hate the betrayers" among them, a top Communist Party official, Thai Ninh, was asked if he felt betrayed by Gorbachev and Russian President Boris Yeltsin. "It's better to let the Soviet people decide that," he said.