Can the Petraeus magic work in Afghanistan? is the question being asked in military circles. General David Petraeus, the architect of the surge, has left Baghdad to take over as commander of US Central Command at the end of the month. The new bailiwick of the man known affectionately as King David includes the hotspots of Iraq, Iran, Syria, Pakistan. But perhaps the greatest immediate challenge is Afghanistan; yesterday Brigadier Mark Carleton-Smith, the British Forces commander in Afghanistan, said decisive victory against the Taleban was unrealistic.

General Petraeus, one of the most committed and experienced counter-insurgency experts after his four and a half years of top command in Iraq, will not be in a position to mastermind day-to-day operations in Afghanistan as he did so effectively in Baghdad, especially during the surge period when 30,000 extra American troops were drafted into the Iraqi capital and elsewhere to protect the people from al-Qaeda and Sunni insurgents.

The lessons he learnt in Iraq, however, will play a key role in the way he addresses what has become an incoherent political and military campaign in Afghanistan; but the counter-insurgency guidance he drew up for Iraq that has become the bible for all military commanders, including the British who thought, wrongly, they knew everything about the subject after Malaya and Northern Ireland, cannot easily be transferred to deal with the Taleban because the economic, social and political conditions are so different.

Despite the ravages of the Saddam Hussein era, Iraq had infrastructure suitable for foreign military occupation, and, above all, it has vast oil and natural gas wealth and as the Land of the Two Rivers, it is blessed with water, with huge potential for agricultural development. Investment is beginning to pour in from Arab countries, now that the violence has been reduced dramatically.

Afghanistan, on the other hand, presents a far greater challenge. Its opium-dependent economy, which leaves a trail of corruption from the highest level in Kabul all the way downwards, severely undermines all attempts to convert the country into a law-abiding, stable environment. It is not even practical to order a Baghdad-style troop surge to protect the Afghan population in the south from Taleban malevolence. Unlike Iraq, there is not enough ready-made infrastructure to accommodate them.

In Helmand province where the British troops are based and where the Taleban are strong, the landscape is desert cut through by a fertile green valley where poppies are grown. There is no network of roads and the local inhabitants, including the Taleban, live in thick-walled compounds. To monitor and deter the Taleban in the north, the Royal Engineers have had to construct primitive, makeshift fortresses. The conditions are extraordinarily crude and harsh.

After three decades of war, the Afghans in the remoter regions such as Helmand and neighbouring Kandahar also have little faith either in their own leaders in Kabul or the foreign forces supposedly there to protect them. They hate the Taleban because of the brutal regime they ran before being overthrown in 2001 and would prefer to place their lives in the care of their tribal leaders; but they desperately want security and order, and the Taleban are clever at promising to protect them.

The most General Petraeus can expect in the way of reinforcements for Afghanistan are the proposed 3,500 additional US troops expected in January and possibly a further two US combat brigades next year.

As for the rest of Nato, the British Government has effectively declared that 8,000 is the troop ceiling, and other alliance members, such as France, have offered only small additions. The statistics tell the story. In Iraq there are currently about 165,000 foreign troops; in Afghanistan there are 65,000, split between Nato's International Security Assistance Force, under one commander, and the 19,000-strong US-led Combined Joint Task Force 101 which oversees security operations in the east under Operation Enduring Freedom, commanded by a separate American general. This is going to change, and, sensibly, one US general will take command of both, but the operations will still remain separate entities.

Petraeus is believed to have envied his counterpart in Afghanistan when he took charge in Baghdad, but he will feel differently now, faced with the problem of how to reverse the spiral of violence in the south and around Kabul, and, above all, how to stop the never-ending flow of fresh Taleban fighters coming across the border from the tribal regions of Pakistan. He will probably spend more time in Islamabad than in Kabul.

Some of the Petraeus counter- insurgency lessons from Iraq could prove effective in Afghanistan. His motto in Iraq was to “secure and serve” the population, and to live among the people, not stay hidden in fortified barracks. He liked to say: “You can't commute to this fight.” His objective was to pursue the enemy relentlessly, preventing them from enjoying sanctuary anywhere. One successful ploy was to establish what he called “crow's nests”, bullet-proof observation posts that were helicoptered on to flat rooftops overnight.

He also developed a system known as the Anaconda strategy under which every possible element of counter-insurgency was used in Iraq, including political reconciliation, engagement with Syria through which foreign suicide-bombers moved, anti-terrorist operations and a profusion of intelligence and surveillance missions; all aimed at squeezing the life out of al-Qaeda and the Sunni insurgents. It worked.

Could the Anaconda approach be replicated in Afghanistan, with Pakistan replacing Syria?

The insurgency is smaller scale in Afghanistan but the Taleban's malign influence and power is spreading, and if they are to be squeezed out, combat must be combined with a skilful political and diplomatic campaign, and, most importantly, a tireless information war to draw in the ordinary Afghans as well as Taleban members who fight for money, not fanatical ideology, and might be persuaded to swap sides.

This approach succeeded in Iraq. Petraeus set up a “strategic engagement cell”, partly staffed by senior British commanders, who sought out Sunni insurgents, many of whom metamorphosed into Sons of Iraq, the organisation that burgeoned into a huge neighbourhood- protection militia force. Perhaps the Sons of Afghanistan could be formed.

Even with King David in charge, this Iraqi-style approach is unlikely to bear fruit in Afghanistan for many years. There is too much to put right and too many obstacles in the way.

Michael Evans is defence editor of The Times

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