Can Afghanistan stay the course? Five years after the overthrow of the Taliban, a fragile democracy is struggling to survive, even with the help of U.S. troops.

Afghans used to call Lashkar Gah "Little America." The capital of Afghanistan's Helmand Province was a modern city, built up by the United States during the Cold War, with suburban-style houses and a hydroelectric dam. In 2001, it seemed like fertile ground for the U.S.-led effort to stabilize the country after the ouster of the Taliban--a brutally repressive Islamic regime.

Today, Little America is plagued by a resurgent Taliban. They have set up checkpoints on the roads and disrupted reconstruction projects. Helmand is at the epicenter of an explosion in drug trafficking that has claimed the lives of more than 100 American and NATO soldiers this year and doubled American casualty rates countrywide.

Helmand's descent symbolizes how Afghanistan has evolved, since the overthrow of the Taliban in 2001, into one of the most troubled fronts in the fight against terrorism. Roadside bomb attacks are up by 30 percent; suicide bombings have doubled. Statistically, it is now nearly as dangerous to serve as an American soldier in Afghanistan as it is in Iraq. (There are about 23,000 American troops in Afghanistan.)

The U.S. and its allies promised to help Afghanistan rebuild and establish a democratic government, and the country has taken significant steps toward that goal. In October 2004, Hamid Karzai won Afghanistan's first presidential election. Last year, Afghans elected a Parliament. And a new Constitution, which combines Islamic and democratic principles, recognizes women as equal citizens.

At the same time, 80 percent of Afghanistan's women are illiterate and, in some conservative regions, must still wear head-to-toe cloaks called burkas whenever they go outside their homes. Afghanistan is one of the world's poorest countries, with most people living on less than a dollar a day. Karzai's government has increasingly been criticized for corruption and inaction. Many Afghans are frustrated that the U.S.-led coalition has failed to stop the resurgent Taliban.

AFTER THE SOVIETS

In Helmand, the absence of security and government control has enabled the province to become Afghanistan's largest grower of opium poppies, which are used to make heroin. The country's opium harvest this year has reached the highest levels ever recorded at 6,100 metric tons--about 92 percent of the world's supply.

Many of Afghanistan's troubles stem from the 1979 invasion by the Soviet Union, which led to a 10-year war between the Soviets and Afghan guerrillas called mujahideen. The U.S. saw the mujahideen as allies in the Cold War struggle with the Soviets and backed them with $2 billion. But when the Soviets withdrew in 1989, the U.S. cut its aid to Afghanistan. The country descended into civil war, with different factions battling for power.

The Taliban seized control in 1996. They ruled for five years, imposing restrictions such as a ban on education for girls. They also provided a base of operations for terrorist groups like Al Qaeda and its leader, Osama Bin Laden.

In retaliation for the 9/11 attacks, the U.S. launched attacks against Al Qaeda camps in Afghanistan in October 2001. Within a month, the Taliban regime had fallen. Remnants of the Taliban and A1 Qaeda escaped into the mountains along the 1,500-mile border with Pakistan, where Bin Laden is thought to be in hiding. (See Asia map, p. 28.)

Richard Boucher, Assistant Secretary of State for South Asia, defends the progress in Afghanistan. He says 1.6 million girls are attending school, and 730 miles of roads and 1,000 schools, clinics, and government buildings have been rebuilt.

But members of Congress and former administration officials argue that missteps by the U.S. and its allies squandered an early opportunity to bring order to Afghanistan so that it could be more completely rebuilt. And some critics say that the U.S. paid less attention to Afghanistan after the war in Iraq began.

"I think the mission continues to be doable," says James Dobbins, a former Bush administration envoy to Afghanistan. "But it's going to be a longer, harder, more expensive mission by virtue of the fact that we did not seize opportunities."

David Rohde is an investigative reporter for The New York Times; additional reporting by Carlotta Gall.