Boris Gromov was the last Soviet soldier to leave Afghanistan. The commanding general's lonely retreat on foot across the Friendship Bridge spanning the Amu Daria river on Feb. 15, 1989, was the symbol of a superpower humbled.

"I felt that a huge burden had lifted when I crossed that border," he recalled in an interview today.

As the United States threatens to go to war in the same rugged land that defied its would-be Soviet conquerors, Gromov and many other veterans of the decade-long war in Afghanistan, which has been called the Soviets' Vietnam, can think only of "the sea of bloodshed" it would take to win.

Now the governor of the Moscow region, Gromov denounced the terrorists who carried out last week's attacks on the World Trade Center and the Pentagon as "animals," and -- like much of Russia -- he said that "powerful strikes" must be delivered in retaliation. But he also remembered the first time his column was ambushed, deep in a gorge, back in 1980 -- and the daily pointlessness of hunting down mujaheddin leaders who could not be caught -- and the 1 million Afghans and 15,000 Soviet soldiers who died because of what Gromov once famously called "a political mistake."

"For the Americans, introducing land forces would not lead to anything good," he said. "It would not bring anyone laurels."

As Russia wavers on whether and how to support the United States in fighting what President Vladimir Putin has called a "common enemy," Gromov's story is a reminder that Russia's ambivalence is not just the lingering mistrust of a former Cold War rival. Neither is its hesitation due only to concerns about the United States getting involved militarily with the Central Asian countries in Russia's traditional sphere of influence on its southern border.

Instead, Russia's reluctance reflects the country's conviction that Afghanistan is a place where a war cannot be won, where high mountain gorges still hold the terrifying memories of a thousand ambushes and where controlling the cities never meant subduing the land. In interviews over the past few days, several of the top Soviet commanders from the Afghan war agreed that a U.S. ground war there would be "useless," as retired Gen. Makmut Goryeev put it, and "inexpedient," as former Gen. Valentin Varennikov said.

"The American army will meet with fanatical resistance," said Ruslan Aushev, who commanded a motorized infantry battalion in Afghanistan and is now president of Ingushetia, an internal Russian republic.

"The Americans can launch an attack that will look really dramatic and effective on television, but I don't think the result will be the expected one. Even with all the power of the American army, it will not reach success," he said.

The Soviet incursion into Afghanistan began at Christmas 1979 as an effort to block the ouster by Islamic rebels of a recently installed, Moscow-backed government in Kabul. Hundreds of Soviet special forces, disguised as Afghan troops, conducted a raid on the presidential palace in which the president, Hafizullah Amin, was killed. Two days later, thousands of Soviet troops poured across the border from Uzbekistan, Turkmenistan and Tajikistan.

More than 100,000 Soviet troops were stationed there at any one time during the war. It became a brutal, asymmetrical struggle in which Russians often resorted to overwhelming force in unsuccessful efforts against elusive targets, a strategy similar to that conducted more recently inside their own borders, in Chechnya.

"The Soviet Union had a bloody, bad experience in Afghanistan," said Aleksandr Golts, a military analyst who covered the war. "Afghanistan is a tough country for any intruder. The culture, the geographical environment -- everything gives a lot of opportunities for guerrilla war in which modern army methods are more or less useless. Our armed forces came prepared for the Cold War, for general battle, and they were completely ineffective."

Then-Soviet President Mikhail Gorbachev called it a "bleeding wound," and ordered the pullout in 1988. By the time Gromov retreated across the bridge alone and embraced his teenage son in February 1989, the war's fallout was already hastening the breakup of the Soviet Union that would come two years later.

"The way they sent the Soviet army into Afghanistan was simply a crime," general-turned-politician Alexander Lebed said in a 1994 interview. "They had no idea of what they were getting us into, they knew nothing of the country or its people. It seems to me that they didn't even have a strategic plan."

This week, Lebed said the United States also would find Afghanistan unconquerable. "All of the stockpiles of bombs in both the United States and Russia would not be enough to solve this problem," he said in a telephone interview from Krasnoyarsk, where he is governor.

Asked to recall his impressions of the war, he listed "lice, dirt, blood." The Soviets' tactics of destroying villages made clear the danger of retaliatory strikes, Lebed said. For every town annihilated, "perhaps one mujaheddin was killed. The rest were innocent. The survivors hated us and lived with only one idea -- revenge. They are wolves, these people."

Such tactics, Lebed said, created today's Afghanistan, "a miserable and destroyed country. We left because we came to realize that the whole country had begun to hate us."

One consequence of the Soviet involvement was the arrival of Osama bin Laden, now the chief suspect in the Sept. 11 attacks, and thousands of other Arab Islamic militants who joined the U.S.-supported Afghan resistance.

Goryeev recalled his first encounter with bin Laden and his men during the battle for Jalalabad in early 1989. Officially, the Soviets had already withdrawn their troops, but Goryeev had stayed behind to oversee the effort to help prop up Moscow's puppet government.

"Bin Laden fought with money and he fought with terror. He paid the fighters $200 a day to fight against the Soviet troops. And he prepared a whole range of subversive acts -- every day there were explosions at marketplaces, offices, against troops. He paid very generously for all terrorist acts," Goryeev said.

Today, bin Laden is once more operating out of Afghanistan, his enemy no longer a Soviet Union that has ceased to exist but the United States that once funded the holy war against Moscow's Communist leadership.

Many former Soviet generals like Goryeev cannot forgive that. "Let us not forget," he said, "that he was created by your special services to fight against our Soviet troops. But he got out of their control."

Commanding Gen. Boris Gromov, the last Soviet soldier to leave Afghanistan after a decade-long war, is accompanied by his son, Maxim, as he crosses over the Amu Daria river in February 1989.