Britain and the US, which withdrew troops from Afghanistan to fight the war in Iraq, are now reversing the flow in a drive to capture Osama bin Laden. With Saddam Hussein in custody, catching the al-Qai'da leader would be a major election-year coup for President Bush.
Signs of quickening activity in the eastern Afghanistan included an announcement yesterday that US special-operations snipers killed nine suspected Taliban fighters in one of the deadliest engagements involving American forces in months. There was no confirmation whether the clash marked the start of a promised spring offensive that has Bin Laden as a top target.
The US is carrying out a broad "troop rotation" in Iraq which is expected to reduce its total forces there from around 132,000 at the beginning of the year to just over 100,000 by May. At the same time it is beefing up its forces in Afghanistan. But simple numbers obscure a change in priorities: while many of the new troops heading for Iraq are reservists or National Guard members, more seasoned soldiers are being deployed in the hunt for Bin Laden, who is thought to be hiding in the mountainous border region between Pakistan and Afghanistan.
Task Force 121, a special forces unit created to lead the search for Saddam, has now moved to eastern Afghanistan, where many of its members have served before. Heavily bearded Delta Force soldiers and Navy Seals in local dress have been seen in villages close to the border with Pakistan, and Britain is sending in SAS detachments.
They are soon to be joined by company-sized regular units which will remain in an area for two to three weeks at a time, seeking to gather information and win local support with civil aid projects, such as digging wells. "Previously they never established any presence, because they did not stay long enough," said a recent visitor to the border region near Khost.
The Americans hope to avoid the errors they made in December 2001, when Bin Laden was pursued to the mountainous Tora Bora area further north. They relied on Afghan warlords of dubious loyalty to spring the trap, and failed to get Pakistan to secure the border, enabling the al-Qa'ida leader to slip away with ease. This time the US has enlisted the support of Pakistan's President, General Pervez Musharraf, whose forces have sealed off mountain passes and mounted sweeps - so far fruitless - in the wild tribal areas of northern and southern Waziristan.
Washington has made little secret of the operation, hoping it will generate electronic traffic among al-Qa'ida militants that might lead to Bin Laden. But Dr Rohan Gunaratna of the Institute of Defence and Strategic Studies in Singapore, author of Inside al-Qa'ida: Global Network of Terror, said: "His security is very good. He mainly uses human couriers and avoids communications methods susceptible to surveillance."
The Pakistan-Afghanistan border is more than 1,500 miles long and Bin Laden spent a long time in the region in the 1980s and 1990s, added Dr Gunaratna. "Without precise intelligence it will be impossible to locate him."
But as the terrorism expert said, "some operations are driven by political necessity". American forces on the ground can expect all the firepower, intelligence help and political back-up they need to track down Bin Laden, because it could make re-election for President Bush in November a near-certainty. Not coincidentally, the Secretary of State, Colin Powell, is due to visit Afghanistan, Pakistan and India next week for the first time since 2002.
If the Bush administration can metaphorically place the al-Qa'ida leader's head on a pole along Saddam Hussein's, it will also have a powerful answer to critics who argue that the Iraq war, far from advancing the campaign against terrorism, was a distraction and diversion of resources from it. Such a triumph could be even more helpful to Tony Blair, who has an election of his own to fight in the next 18 months or so, and who is suffering far more than his ally from public scepticism over Iraq.
But the renewed focus on Afghanistan and Osama bin Laden will highlight other uncomfortable aspects of the fight to curb global terrorism, not least the West's dependence on Pakistan.
"Four hundred and seventy members of al-Qa'ida have been captured on Pakistani soil, or just over a quarter of the detainees in Guantanamo Bay," Dr Gunaratna pointed out. "General Musharraf is a very close ally in the fight against the al-Qa'ida network - but unfortunately he may not live long."
The Pakistani leader has survived half a dozen attempts on his life by Islamists, who are mainly spurred on by his co-operation with the US. If he fell from power before Bin Laden was captured, Pakistan could well come under the control of forces sympathetic to al-Qa'ida and its former Taliban hosts in Afghanistan. Not only did the country's powerful ISI military intelligence organisation largely create the Taliban - which remains a disruptive force in Afghanistan - it also sponsored the development of Pakistan's nuclear weapons.
We now know that, thanks to Abdul Qadeer Khan, the "father" of Pakistan's nuclear programme, the technology was exported to Iran, a member of Mr Bush's "axis of evil", as well as to Libya, which has agreed to give it up. When Dr Khan's activities were exposed, General Musharraf could do no more than pardon him: although nobody believes that the Pakistani authorities were ignorant of his nuclear proliferation, he is a hero to his countrymen.
If a nuclear weapon ever fell into the hands of terrorists, it would almost certainly be as a result of the actions of Pakistan, a supposed ally in the "war on terror", and not Iraq, which - we also now know - did not have the technology. Yet Tony Blair, in his speech last week justifying his stance on Iraq, referred to the Khan affair only in passing.
Elsewhere in the speech the Prime Minister said: "It is a matter of time unless we act and take a stand before terrorism and weapons of mass destruction come together." But when Mr Powell arrives in Islamabad he is not expected to criticise General Musharraf for pardoning Dr Khan: the Pakistani leader's position is too fragile.
If Bin Laden is to be captured, the ISI's co-operation will be required. General Musharraf has done his best to purge the shadowy organisation of Islamist officers, but the ISI is still believed to work closely with radical religious groups at home and armed movements in Afghanistan and Kashmir.
This is likely to be overlooked by Washington, however, along with many other issues, if Pakistan can help deliver the prize an electioneering President Bush craves above all else.Reuse content