Afghans Going Home--to a Region Littered With Arms, Addicts : Legacy: War left world’s largest refugee population. It is returning to a corrupt land of social destabilization.

Amid the jagged peaks and rocky gorges of the fabled Khyber Pass, Afghan refugee Mohammed Aslam is finally going home.

Bearded and bony, with a gun at his side and a turban on his head, the 50-year-old farmer hunches at the wheel of a giant green truck piled high with beds, boxes, wooden beams, even a newly bought donkey. Several women in billowing black robes, and at least a dozen children, cling to the swaying load.

Aslam fled his village in eastern Afghanistan in 1979 after Soviet troops invaded to prop up a Communist regime. When Islamic resistance fighters, U.S.-trained and -armed, rebelled, the country became a Cold War battleground, forcing an estimated 5 million refugees into camps scattered in the stony deserts and rugged mountains of Pakistan and Iran.

Now, a year after the rebels won control of Kabul, the world’s largest refugee population is heading home. The United Nations estimates that 1.5 million Afghans returned to their war-ravaged villages last year; 2 million more are expected to go this year. Even the once-packed International Committee of the Red Cross hospital in Peshawar, Pakistan--the staging area for the resistance--is closing.

“I’m very happy,” Aslam said with a gap-toothed grin as he joined the refugee stream in this dusty border town. “It’s peaceful now. There’s no problem.”

But the problems are hardly over for Afghanistan--or its former patrons. Washington funneled billions of dollars through Pakistan to support the Afghan war against Moscow. And the grim legacy of that proxy war is an explosion of drugs, guns and corruption affecting millions of people across Southwest and Central Asia.

“My assessment is this region is going to remain destabilized for the next 15, 20 or 25 years,” said a senior Pakistani intelligence official. “We already have total social destabilization of Pakistan. Total.”

Ironically, refugees are part of the problem. With their country in ruins, many are going back to cultivate a crop that needs little water or fertilizer: poppies. The resulting raw opium is refined into heroin that quickly finds its way to Pakistan, Europe and the United States. This year’s harvest, now under way, promises a bumper crop.

The United Nations already ranks Afghanistan as the world’s No. 1 supplier of opium, with an estimated 2,000 tons produced last year. The United States, which uses satellite photographs, figures it was 670 tons, making it second to Myanmar and the Golden Triangle region in Southeast Asia.

Either way, says a U.S. narcotics agent, Afghan opium production will be “significantly higher this year,” perhaps double last year’s supply.

About half the 60,000 refugees in the Katcha Garhi camp have gone home, for example. “Most will plant poppies,” said Mohammed Talib, a worker in the camp. “When I go back, I will too. What else can I do? I am a teacher, but there are no schools. No factories. No work. No irrigation. How can we eat?”

Talib’s home is in Nangarhar province in eastern Afghanistan, where more than half the poppies traditionally are grown. Before the war, most opium was hauled cross-country and smuggled to Turkey for refining into heroin.

That was impossible during the war, so crude new laboratories sprang up next door in western Pakistan. About 100 labs are now believed to flourish in the lawless tribal areas southwest of Peshawar. So do local poppies.

One result is that Pakistan now has a growing number of addicts. By all accounts, the country had none when the war began. By 1988, the government estimated that up to 1.7 million addicts--or 5% of the adult male population--were smoking locally refined heroin; unofficial estimates now are even higher.

Still, experts say that enough heroin is left to supply 20% of America’s demand. Some is smuggled on ships; several hundred pounds have been seized on Pakistan International Airlines flights to New York. Europe is easier: The opening of Afghanistan’s long-closed northern borders into former Soviet republics means smugglers’ trucks now can reach Amsterdam in a week.

Addicts aren’t Pakistan’s only worry. A kilogram of heroin costing $2,000 in the Peshawar bazaar may bring $100,000 in New York, and millions of dollars more when it’s cut for street sales. That means astronomical profits--and equally high levels of corruption.

A study commissioned last year by the CIA concludes that drug profits have penetrated Pakistan’s “highest political circles” and are “fast becoming the lifeblood of Pakistan’s economy and political system.”

A separate U.S. report, part of a worldwide narcotics report to Congress this month, noted that at least three powerful members of Pakistan’s National Assembly are reputed drug traffickers. Heroin processing continues “virtually unhampered,” the report said, and prosecution of major traffickers is “minimal.”

“This is not Colombia . . . yet,” said a U.S. drug agent, referring to the South American country in the grip of cocaine cartels. “That’s the best way to put it.”

Unfortunately, most Afghans have only one obvious alternative to selling drugs: selling guns.

Perhaps no people in the world are as heavily armed as Afghans. Here in the Khyber, every other man carries an assault rifle or grenade launcher. Homes are huge, mud-walled fortresses, complete with battlements, turrets and gun ports. Fierce and fearless Pushtun tribesmen, after all, bested the Moguls, British and Russians over the centuries.

The only difference now is that Afghans control what the Pakistani intelligence official called “the greatest armaments and ammunition supply depot in the world.”

He said retreating Russians left 10-year stocks of arms and ammunition in some areas. Fleets of tanks, armored vehicles and helicopters were captured or abandoned. The bonanza includes millions of Kalashnikov assault rifles. Countless other weapons were provided by the United States.

“In Afghanistan, there is no civilian population,” the official said, shaking his head. “They’re all armed. . . . There are individuals who have tanks and armored personnel carriers.”

With so many guns, business is booming. Guns and explosives, apparently from Afghanistan, were used by terrorists in the March 12 bombings in Bombay, India. Other Afghan weapons have been smuggled to Muslim guerrillas fighting in Kashmir, a disputed state that already has sparked two wars between India and Pakistan.

To the north, many of the Islamic fundamentalists fighting the elected government in Tajikistan were trained and armed in Afghanistan.

“There are truckloads of weapons coming from Afghanistan,” said a nervous Western diplomat in Karachi, Pakistan’s largest city, which is now under military control because of growing lawlessness and violence. “Go to someone’s home now, you don’t see a bodyguard. You see a small army.”

Real armies, of course, are still fighting in Kabul. The Afghan capital has been nominally ruled by an Islamic coalition since the Marxist regime collapsed a year ago. But it is a government in name only. The city has been pounded by fierce rocket, artillery and bombing attacks from rival Muslim groups based in hills nearby.

The vicious power struggle between government troops loyal to President Burhanuddin Rabbani and those under hard-line fundamentalist chief Gulbuddin Hekmatyar has left at least 5,000 people dead, mostly civilians. Several cease-fires have collapsed, and no solution appears imminent.

“Our problem is a power restructuring in Afghanistan,” said Hamed Karzai, deputy foreign minister of Rabbani’s government. “For 14 years, there was an effort to impose a structure on us. The Soviets tried it, and those who helped the moujahedeen (guerrillas) tried it. The structure they wanted to impose didn’t take root. It failed. The result is a vacuum.”

The real result is severe hardship. Kabul was hardly damaged in the long war. But now most residential and commercial areas are in ruins. There is no running water, heat or electricity. Hotels, schools and offices have closed. Most embassies and humanitarian agencies, including the United Nations, have pulled out.

Security isn’t much better outside Kabul, where warlords and anarchy reign. Three U.N. workers and a Dutch engineer were shot and killed in eastern Afghanistan on Feb. 1 in what U.N. officials call an assassination. Soon after, a U.N. relief convoy, the first since December, was hijacked while trying to deliver fuel and medicine to Kabul’s five remaining hospitals.

“We cannot continue giving assistance . . . when our convoys are hijacked,” complained Sotirios Mousouris, special U.N. representative for Afghanistan. He estimates that 2 million Afghans “desperately” need food, medical care and other emergency relief. Postwar development and reconstruction are still a dream.

The United Nations has asked its members for $138 million for Afghan aid this year. So far, only $17 million has been pledged. Among the most critical needs is to clear millions of mines littering fields, roads and villages. A dozen mine clearers, as well as countless Afghan civilians, already have been killed from this deadly harvest of a distant war.

“Afghanistan was one of the most tragic victims of the Cold War,” Mousouris said sadly. “And it’s one of the most tragic victims of the end of the Cold War. Because it’s becoming a forgotten tragedy.”