Everyone in this part of Helmand is waiting for the arrival of “The Businessman” – a mysterious individual who turns up at about this time each year to buy poppy resin from the acres of crops in the green belt along the Helmand river.

No one knows what nationality he is – Afghan, Pakistani or Iranian – but during the winter he turns up with cash to pay the farmers to keep them in food and supplies, on the understanding that he gets the lion’s share of the poppy resin the following April or May. Even the locals refer to him as The Businessman, never putting a name to the one who guarantees them an income, although the farmers receive a meagre wage for a product that generates millions of dollars further up the drugs chain as heroin in the rest of the world.

The Taleban demand one kilo of the poppy resin for every ten produced, telling the farmers it is a tax that they have to pay. But The Businessman scoops up the rest, and neither the farmers nor the Taleban interfere. As one British Army officer said: “This is real Mafia territory; it’s like The Sopranos but without the humour.” For the British troops at Forward Operating Base (FOB) Inkerman, a Rorke’s Drift of a place between Sangin to the south and Kajaki to the north, there is nothing they can do to stop the trade. That is the job of the Afghan police’s counter-narcotics teams. But in this swelteringly hot, dusty location – desert on one side, poppy-growing fields on the other – there is no sign of anyone trying to prevent the poppy harvest, let alone seeking to uncover the identity of the man who stands to profit the most.

From the ramparts of FOB Inkerman, crafted by Royal Engineers out of a deserted compound, the soldiers of B Company 2nd Battalion The Parachute Regiment keep a wary eye on all the activity. Among the farmers and their families scraping off the resin as it oozes from slits made with razor blades in the poppy heads, there are probably lower-tier Taleban helping out, ensuring they get their money’s worth when the harvesting finishes in less than three weeks. They spend the cash on more arms and ammunition to fight the British.

It already looks like a bumper harvest. Wherever you look in Helmand, where the bulk of Afghanistan’s poppies are grown, there are fields and fields of poppies. Last year, as part of the Government’s eradication programme, about 3,000 acres (1,215 hectares) of poppy crops in Helmand were destroyed – out of nearly 100,000 acres in the province.

British officials acknowledge that it will take at least 20 years to rid Afghanistan of its opium economy. In the meantime, with the Government and international community pecking around the edges of the poppy business, the farmers carry on with their normal lives, catering for their families but also for the Taleban, the drug barons and their intermediaries.

Poppy farmers here say that it takes 20 days to harvest the crop and they are already three days into the time-table. The resin is put into saddlebags and containers, and when the scraping is completed the first of the “jingly trucks” will arrive to pick up the opium and take it on to Garmab, up the road north towards Kajaki.

Once the poppy harvest is over, the troops at FOB Inkerman are sure that the Taleban will go back to attacking them from across the fields, hiding in the deep irrigation ditches and wheat crops that grow to chin height. The Taleban are concentrated here mainly in an area known as Jusaly, consisting of about 15 villages to the west of FOB Inkerman. The soldiers can see Jusaly from the ramparts.

No one is expecting any full-scale assaults – the base is too well defended, as the Taleban know. But they have a range of weapons that pose a threat through indirect fire, including the RPG7 rocket-propelled grenade, a recoiless rifle called SPG9, 107mm Chinese rockets and the fearsome Russian DshK, a 12.7mm antiaircraft gun.

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