PETER J. GANCI AIR BASE, Kyrgyzstan – Four months ago, this was a muddy prairie next to a sleepy airport in what used to be a nearly forgotten part of the Soviet Union.

Today it looks like a scene from "M*A*S*H" and is at the new front lines of the American military presence. Nearly 2,000 soldiers, about half of them American, are camped out here in air-conditioned tents.

At the landing strip nearby, FA-18 fighter jets and French Mirages take off on daily sorties over Afghanistan, rattling the windows of nearby farmers as they roar into the sky. Spanish, Dutch and Danish cargo planes fly in and out as well, along with KC-135 tankers to provide the combat jets with in-flight refueling.

"Everything you see here has literally been done since the middle of January," said Gen. Wayne Lloyd, who returned to active duty with the Air National Guard to take on the job of base commander in mid-March. "This was done in the dead of winter, in the middle of frostbite-freezing cold."

Officially, the air base here, named after the New York City Fire Department's highest-ranking uniformed officer, who died in the World Trade Center attack on Sept. 11, is only temporary and will be closed after the war in Afghanistan has ended. But no one knows just how long the mission will last, or even how its end will be defined.

"We will stay as long as it takes," General Lloyd said. "I can't say when that will be, but I don't think it will be in the next few weeks."

Kyrgyzstan, a impoverished former Soviet republic with five million people, is one of several Central Asian countries that have abruptly become important strategic allies of the United States. It shares a border with Afghanistan and quickly opened itself to the American-led military coalition that declared war on the Taliban regime.

About 2,000 American troops are also stationed in neighboring Uzbekistan, at Hanabad, near the border with Afghanistan. A small contingent of American soldiers is in Tajikistan, one of the poorest and most chaotic countries in Central Asia.

Though almost everyone here lives and works inside tents, the elaborate infrastructure implies a more extended presence.

The base has a central power plant, its own hospital center, two industrial-sized kitchens, a recreation center and an expansive fitness center. Soldiers can watch live American sports on wide-screen television sets. They can send e-mail at what amounts to an Internet cafe. They can work out on weights, treadmills and cycling machines.

The population has grown so quickly that French forces here decided to set up the second of those kitchens, catering to French tastes.

"I could tell from the start that this would be one of the better bases," said Clint Parks, an airman who came here two months ago and had previously worked at the air base in Kuwait. "The living conditions are great here. I was surprised by how much they have."

Inevitably, the buildup here and in neighboring countries has provoked uneasiness.

Russian leaders have been remarkably supportive of the effort, given how intensely they resisted the expansion of NATO into Poland and the Czech Republic. But diplomats and regional experts say that both Russia and China are uncomfortable about American forces so close to their borders, and they predict that tensions will escalate if the bases stay in place longer than expected.

Air Force officials here estimate they have already pumped more than $13 million in cash into Kyrgyzstan's economy. A single takeoff or landing can cost as much as $7,000 in fees paid to the government. The base has spent millions of dollars on everything from gravel and jet fuel to televisions, computers, cell phones and even guided tours.

That is a lot of money in a country where the average person earns about $270 a year and the national debt is equal to about $300 a person.

American officials have also increased economic aid sharply, not just to Kyrgyzstan but to Uzbekistan and Tajikistan as well. The State Department also recently announced plans to provide about $30 million to help Central Asian countries fight trafficking in weapons, and $20 million to help Uzbekistan strengthen export controls and border inspections.

In theory, the flow of new money ought to make life better for people in these countries. But none of the Central Asian countries are bastions of good government.

Kyrgyzstan remains one of the world's most impoverished countries. It has made a genuine effort toward democracy and Western-style economic reforms, but it can hardly yet be called democratic. In March, the police killed seven people and wounded more than a dozen others who were protesting the imprisonment of a member of Parliament.

Uzbekistan remains notorious for brutal political repression as well as for corruption and hostility to market-opening economic reforms. Tajikistan, which was embroiled in civil war for five years, remains a major corridor for heroin traffickers and so hostile to economic reform that Western aid institutions have almost stopped providing help.

It is perhaps not surprising that people who live near the new air base here fail to see it as a boon to their pocketbooks.

"When the Mirages take off, the noise rattles the windows," said Sonya, a woman in the nearby village of Mramornoe who was unwilling to give her last name. "They take off at all hours of the day and night, and it really bothers me. It also bothers the animals. The hens are not laying eggs."

A Kyrgyzstani public television station recently reported that 60 percent of people surveyed around Bishkek, the capital, which is nearby, would just as soon not have the base.

Local villagers are quick to explain why. Dirt roads and open fields near the airport have been cut off. Local people who board buses at the airport for the ride into Bishkek now have to show their identity papers because the airport has become a restricted area. Furthermore, although the foreign soldiers seem friendly, they spend little money locally.

"We don't see any benefit to us," said Nina Grigorevna Haritonona, a retired doctor in Mramornoe. "They don't spend any money here. They even have their own food."