A mile from South Station, an outpost of US marines in Helmand province, the tribal chief was openly hostile. “The Americans threaten our economy and take our land for bases. They promise much and deliver nothing,” he said.

“People here regard the American troops as occupiers,” said Haji Khan, a leader of the Baluch tribe, who rules like a medieval baron. “Young people are turning against them and in time will fight them.”

Inside South Station, soldiers are proud of the progress they have made. Until they arrived, this remote part of Helmand had not had a government presence for years. But many are pessimistic about where the conflict is heading.

“I’m not much for this war. I’m not sure it’s worth all those lives lost,” said Sergeant Christian Richardson as we walked across corn fields that will soon be ploughed up to plant a spring crop of opium poppy.

A New Yorker who joined the marines after 9/11 and served two tours in Iraq, Richardson, 24, said his men had achieved much. “You can see we are making progress, slowly. But when we leave, the Taliban and Al-Qaeda will surely return.”

With enough effort, resources and time, the marines are confident the population can be won over. But, with the platoon’s influence limited to a small area around their base, many soldiers wonder if the Taliban and Al-Qaeda may simply outlast them, or if the US and Afghan governments have the resolve to send enough troops to win.

Third Platoon, Charlie Company of the 2nd Light Armoured Reconnaissance Battalion, came last July to Khan Neshin, as far south as Nato soldiers have reached in Afghanistan. It was part of a summer offensive by more than 4,500 troops of the Marine Expeditionary Brigade, which has joined British and other forces trying to turn the war in Helmand.

Although they have read the manuals on counterinsurgency and heard generals speak about how to defeat the Taliban, the reality has been bloody, painful and frustrating.

The platoon knows there are at least 20 booby-trapped bombs on the high ground around the base. More than half the men have already been caught in blasts. One marine explosive expert was killed; others suffered broken legs and amputated feet. Three have survived two explosions and come back to fight again.

General Stanley McChrystal, the US and Nato commander in Afghanistan, says the mission is to protect the population and isolate them from the Taliban, but the marines are finding it no easier to defeat the Taliban than it has been for the British, who have fought in the province for three years. Villagers are rarely willing to express a simple opinion, let alone inform soldiers where the enemy is hiding. One marine described the way the Taliban blended with the population as “unbelievably frustrating”.

In terrain crisscrossed by canals with weak and narrow bridges, the platoon has to approach villages on foot. Even when they have surrounded the Taliban, the marines have found the enemy has an uncanny ability to slip away in the ditches. All this adds to the strain of facing improvised explosive devices, which are the main threat.

“We are all brothers here,” said Lance-Corporal Corey Hopkins, 22, from Georgia. “And it hurts to see your brother hurt or put him in a bag for the last time. It pisses you off. It makes you mad. You know people out here know what’s going on, but they won’t tell you.”

Corporal Gregory Williams, 22, from North Carolina, said: “It’s going to take a lot of proving out here to make them talk to us. It’s working so slowly.” The marines are trying to implement a strategy dictated from Washington that bids them separate the population from the insurgents. But attempting that means a battle not only against the Taliban but against a feudal system that places real power in the hands of landowners such as Haji Khan.

When we talked to the grey-bearded men in the village, in the shade of one-room mosques, most appeared friendly. Asked if they wanted a school or more doctors, all said such questions were a matter for those who own the fields.

The marines hope to open a school and provide medical facilities. They are also offering to pay Khan and others to provide jobs to improve the canal system.

At a shura, or village meeting, at South Station last Friday, Khan showed up with 40 elders and heard Captain Chris Conner, commander of Charlie Company, promise development. “From the bottom of my heart, I want to say that we are here to help you,” he said.

The villagers welcomed the canal scheme and the idea of making use of a doctor at the base. But Khan and another landowner rejected the idea of a school. “Security is still too bad. We’ve seen how they are burnt down [by the Taliban] elsewhere.”

Some marines were unconvinced about paying money for the canal to a tribal leader and drug baron who gave them almost no help and would probably keep the cash.

Later, a marine intelligence officer said the drug economy and the feudal system made the strategy of winning hearts and minds extremely complex. As drug producers, men such as Khan had a “working relationship with the Taliban”.

Nobody knew of the announcement last week in Kabul of a new round of national elections. Nobody voted in the first round. “We never even heard of elections. If we had, I suppose we might have voted,” said one villager.

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