Bin Laden trail is stone cold

While US forces prepare to smoke out the Taliban leader Mullah Mohammed Omar in his last known lair in Helmand province, US commanders now admit that the trail of Osama bin Laden has gone almost completely cold.

US marines, backed by Cobra helicopter gunships and Harrier fighter cover, are scouring the region around Baghram in the north of Helmand, where Omar is reported to be holed up with 1,500 fighters.

He is now hardly a threat to the Americans or the new interim government in Kabul. The main charge against him is that he invited Bin Laden into Afghanistan in 1996, and allowed him to use the country as a base for a campaign of global terrorism.

Britain is preparing to send 1,500 troops to Kabul to lead the 4,500 strong International Security and Assistance Force (ISAF). The force will take at least another month to deploy fully - half as long as most of the British soldiers will be on the ground, as they are due to come out by the spring.

Under the Military Technical Agreement, which the new force commander Major General John McColl managed to sign yesterday, the force is to be for humanitarian and security operations only. But it will come under the overall command of the US Central Command, whose main preoccupation in Afghanistan will be the tracking down of the remnants of the Taliban, and the hunt for Bin Laden.

Despite the use of a whole range of surveillance equipment - Global Hawk remotecontrol spy planes, satellites, RAF Canberra photo-reconnaissance planes - and intelligence sweeps by Delta Force and SAS patrols, the Allies are struggling with an almost total lack of hard information on Bin Laden's movements for the past month.

The al Qaeda leader and his immediate command appear to have been masters at covering their tracks, leaving false clues and planted rumours about their movements. At the beginning of December the Saudi renegade was reported by "eyewitnesses" to have been preparing the defences of the mountain complex of Tora Bora. Yet so far, searches of the caves in the White Mountains have left little trace of Bin Laden.

The richest seams of rumour now say that Bin Laden and his family have found refuge places in Pakistan, Yemen and maybe remote parts of Afghanistan itself.

A book attributed to Bin Laden's deputy, Ayman Zawahiri, suggests that Bin Laden's command had prepared an elaborate escape plan a few weeks into the air campaign on Afghanistan.

When faced with military defeat, wrote Zawahiri, "the movement must pull out as many personnel as possible to the safety of a shelter".

The book, said to be "a last will and testament", was smuggled to London where it has been published by the Asharq al Awsat newspaper.

The fact that Zawahiri, an Egyptian doctor, is widely believed to be still alive points to another failure of US intelligence, which reported he had been killed in an air strike. American forces still lack a reliable flow of human intelligence, according to defence analysts. "The US forces are great on technology, at watching and listening from the sky," said Paul Beaver, a defence consultant to the MoD in London, "but they are still short on good human intelligence they can rely on."

The Americans are now preparing for a bigger ground deployment in southern Afghanistan as units of the 101 Airborne Division move into Kandahar, where they will relieve the 2,000 men of 15 Marine Expeditionary Unit.

While the hunt for Bin Laden and the Taliban elite goes on, plans for the next stage of the campaign against terrorism in Yemen, Somalia and Iraq will be put on hold.

However, al Qaeda is a more durable and complex organisation than any in the FBI and CIA believed before 11 September. Its footprints have been detected in the bouts of communal violence and terrorism in Chechnya, Georgia, Indonesia, Nigeria, Philippines, as well as Uzbekistan, Yemen, Somalia and Kashmir. With its charismatic leader still at large, it is a force to be reckoned with.