Nato's show of force is also about winning hearts and minds

The decision to publicise the imminent offensive in Afghanistan is all part of the strategy, says Kim Sengupta

Generals repeatedly broadcast that fierce fighting lies ahead and warn that there will be inevitable casualties. The biggest offensive since Suez, or Vietnam, or Iraq – depending on which account one accepts – is about to unfold. Seldom has a military operation received such sustained publicity at the instigation of those preparing to carry it out.

The aim is to retake Marjah, an area in Helmand which passed into Taliban hands several years ago. A few preliminary probing actions have taken place around the enclave. Nato aircraft have been dropping leaflets on the town telling the civilian population to leave, asking the insurgents to lay down their arms and join a reconciliation process.

Taliban chiefs, in turn, proclaim ceaseless resistance, boast of the lethal arsenal they have gathered and the international brigade of jihadists who are flooding to their ranks.

The show of force by the US and Britain is, in fact, designed primarily to avoid a drawn-out conflict. The hope is that militants will not want to take on overwhelming Western firepower. Some may leave, but some among those staying behind may be persuaded to change sides and the much-heralded "reconciling the Taliban" process would get a boost.

General Stanley McChrystal, the US commander of Nato forces in Afghanistan, declared yesterday that the element of surprise was not as important as letting citizens know that an Afghan government will be there to replace the Taliban. "We're trying to create a situation where we communicate to them that when the government re-establishes security, they'll have choices." He sounded a cautionary note: "We do expect a very large number of IEDs."

In Marjah the Taliban were declaring they were "prepared to defeat the infidel invader". Mullah Sharadulldine, who claims to be in charge of 145 men, was one of several commanders keen to throw down the gauntlet. "We are well prepared to fight any kind of attacks by the infidels. We also have brave international Mujahedin beside us and we have expanded our defensive circles," he said.

For the civilians caught in the middle this is a time of intense fear. Those who could fled the town, many for Lashkar Gar, the Helmand provincial capital. "Marjah now looks empty, most of the families have gone," said Kamaledine, a 50-year-old farmer. "But some families are still here. I don't have any money to take my family somewhere safe so I am staying here." Haji Jamaldine, one of those who managed to flee to Lashkar Gar with his family of 15, said: "Nobody from the government has helped us here. We are short of food and water, we do not know what to do."

This is not a new situation in the front lines of the "war on terror". The siege of Falluja in Iraq in 2004 began with similar announcements by American forces. We saw long lines of people leaving the encircled city through checkpoints. Many were families clutching children and possessions, but there were also young men, militant fighters, escaping. But enough of them stayed behind to force the Americans to take the insurgent fortress street by street in bloody battles.

Would Marjah turn into another Falluja? Satellite photographs show that militants are digging trenches, moving heavier weapons. Residents leaving the town report the presence of large numbers of armed men.

Yet, since they lost up to 1,000 fighters during the Canadian-led Operation Medusa in 2006, the Taliban have avoided engaging in semi-conventional warfare and prolonged battles.

Western troops now have US equipment which would provide better protection than was available during Panther's Claw. Last December I accompanied US Marines as they took part in the first military offensive, Operation Khareh Cobra, or cobra's rage, after Barack Obama's authorisation of the Afghan "surge". It was to retake another Taliban stronghold, Naw Zad, and was seen as a dress rehearsal for Marjah.

There, too, surveillance footage showed trenches being dug and booby traps laid. Taliban commanders vowed a fight to the death. We came under frequent ambush, and dozens of bombs were found and destroyed. But very few of the militants chose to stand and fight – around 30 were killed, with doubts whether some were actually fighters – and not a single US Marine was killed or even seriously injured.

Naw Zad also saw the reconciliation process the US and UK want to use in Marjah, modelled on how Sunni nationalist groups in Iraq (the so-called "Sunni Awakening") were induced to turn against al-Qa'ida.

Taliban suspects arrested after the recovery of arms caches, bomb-making material and opium in Naw Zad were taken away in handcuffs – and brought back to their villages 48 hours later and freed into the care of local elders.

Two months on, several hundred families have returned to Naw Zad town centre. That is the plan for Marjah. Brigadier James Cowan, commander of the British force in Helmand, said yesterday: "The decisive phase of this operation is not the clearance, it is actually the hold. I am not going to speculate about how long it will take to clear, but I will be very precise about the hold. The whole point of the hold is for it to last forever."

But one lesson of recent Afghan history is that nothing is forever. The "holding" envisaged will have to be done by Afghan security forces, a key part of Nato's exit strategy, and there are doubts on whether they are ready. There is also ample evidence that the Taliban may choose not to take on Western troops in these operations, but they do come back to fight another day. "Victory" in Marjah will not mean that this long and attritional war is anything like over.