While destroying a field of opium poppies in Uruzgan Province, members of the Afghan Eradication Force came under fire in an ambush apparently orchestrated by the Taliban. Photograph by Aaron Huey. ATLAS PRESS

In the main square in Tirin Kot, the capital of Uruzgan Province, in central Afghanistan, a large billboard shows a human skeleton being hanged. The rope is not a normal gallows rope but the stem of an opium poppy. Aside from this jarring image, Tirin Kot is a bucolic-seeming place, a market town of flat-topped adobe houses and little shops on a low bluff on the eastern shore of the Tirinrud River, in a long valley bounded by open desert and jagged, treeless mountains. About ten thousand people live in the town. The men are bearded and wear traditional robes and tunics and cover their heads with turbans or sequinned skullcaps. There are virtually no women in sight, and when they do appear they wear all-concealing burkas. A few paved streets join at a traffic circle in the center of town, but within a few blocks they peter out to dirt tracks.

Almost everything around Tirin Kot is some shade of brown. The river is a khaki-colored wash of silt and snowmelt that flows out of the mountain range to the north, past mud-walled family compounds. On either side of the river, however, running down the valley, there is a narrow strip of wheat fields and poppy fields, and for several weeks in the spring the poppies bloom: lovely, open-petalled white, pink, red, and magenta blossoms, the darker colors indicating the ones with the most opium.

One afternoon this spring, at the height of the harvest, I drove through the area with Douglas Wankel, a former Drug Enforcement Administration official who was hired by the United States government in 2003 to organize its counter-narcotics effort here. Wankel, who is sixty-one and has piercing blue eyes, was stationed in Kabul as a young D.E.A. official in 1978 and 1979, during the bloody unrest that led up to the Soviet invasion. “I left on a flight to New Delhi a couple of hours before the Soviets rolled in,” he said. “People thought it was because I knew it was coming. I didn’t; I just happened to be leaving on a trip. But the Soviets branded me a C.I.A. agent, and so I couldn’t come back—until now, that is.”

Working first with the D.E.A. and then with the State Department, Wankel helped create the Afghan Eradication Force, with troops of the Afghan National Police drawn from the Ministry of the Interior. Last year, an estimated four hundred thousand acres of opium poppies were planted in Afghanistan, a fifty-nine-per-cent increase over the previous year. Afghanistan now supplies more than ninety-two per cent of the world’s opium, the raw ingredient of heroin. More than half the country’s annual G.D.P., some $3.1 billion, is believed to come from the drug trade, and narcotics officials believe that part of the money is funding the Taliban insurgency.

Wankel was in Uruzgan to oversee a poppy-eradication campaign—the first major effort to disrupt the harvest in the province. He had brought with him a two-hundred-and-fifty-man A.E.F. contingent, including forty-odd contractors supplied by DynCorp, a Virginia-based private military company, which has a number of large U.S. government contracts in Iraq, Afghanistan, and other parts of the world. In Colombia, DynCorp helps implement the multibillion-dollar Plan Colombia, to eradicate coca. The A.E.F.’s armed convoy had taken three days to drive from Kabul, and had set up a base on a plateau above a deep wadi. With open land all around, it was a good spot to ward off attacks.

Much of Uruzgan is classified by the United Nations as “Extreme Risk / Hostile Environment.” The Taliban effectively controls four-fifths of the province, which, like the movement, is primarily Pashtun. Mullah Omar, the fugitive Taliban leader, was born and raised here, as were three other founders of the movement. The Taliban’s seizure of Tirin Kot, in the mid-nineties, was a key stepping stone in their march to Kabul, and their loss of the town in 2001 was a decisive moment in their fall. The Taliban have made a concerted comeback in the past two years; they are the de-facto authority in much of the Pashtun south and east, and have recently spread their violence to parts of the north as well. The debilitating and corrupting effects of the opium trade on the government of President Hamid Karzai is a significant factor in the Taliban’s revival.

The Taliban instituted a strict Islamist policy against the opium trade during the final years of their regime, and by the time of their overthrow they had virtually eliminated it. But now, Lieutenant General Mohammad Daud-Daud, Afghanistan’s deputy minister of the interior for counter-narcotics, told me, “there has been a coalition between the Taliban and the opium smugglers. This year, they have set up a commission to tax the harvest.” In return, he said, the Taliban had offered opium farmers protection from the government’s eradication efforts. The switch in strategy has an obvious logic: it provides opium money for the Taliban to sustain itself and helps it to win over the farming communities.

Wankel had flown in from Kabul five days earlier to meet with the governor of Uruzgan, Abdul Hakim Munib, about the eradication operation, only to discover that Munib had left for Kabul the day before. Wankel was told that a sister of the governor had died or fallen ill—there were several versions—but nobody believed this was the real reason for his absence. Munib, a former Taliban deputy minister, was suspected of retaining ties to the movement. And, Wankel noted, there were poppy fields within sight of Munib’s palace.

“We’re not able to destroy all the poppy—that’s not the point. What we’re trying to do is lend an element of threat and risk to the farmers’ calculations, so they won’t plant next year,” Wankel said later. “It’s like robbing a bank. If people see there’s more to be had by robbing a bank than by working in one, they’re going to rob it, until they learn there’s a price to pay.”

We came to a wide bend in the river, a stretch of good, flat growing land with broad poppy fields. The fields were neat and well tended, and the swollen bulbs beneath the blossoms on their long green stalks were dripping with dark-brown opium. A heady, acrid odor like stale urine hung in the air. Small groups of men and boys were in the fields, scoring the bulbs to bleed the opium. They stopped and stared at us when we drove past, and then continued their work.

Before Doug Wankel could do anything in Uruzgan, he had to talk to the Dutch. In a bewilderingly complicated arrangement, NATO member states have been put in charge of military operations in different Afghan provinces—the British in Helmand, for instance, and the Canadians in Kandahar. Since August, 2006, the Dutch have been in Uruzgan. A seventeen-hundred-member Dutch force occupies a sprawling walled base southwest of Tirin Kot. Smaller bases within the walls house contingents of Australians, U.S. Special Forces, and the Afghan Army. Military aircraft land at and take off from an airstrip there at all hours. There are small firebases elsewhere in the province, but troops at the main base rarely venture far from Tirin Kot.