AMERICA made clear last week that it would attack Taliban forces in their Swat valley stronghold unless the Pakistan government stopped the militants’ advance towards Islamabad.

A senior Pakistani official said the Obama administration intervened after Taliban forces expanded from Swat into the adjacent district of Buner, 60 miles from the capital.

The Pakistani Taliban’s inroads raised international concern, particularly in Washington, where officials feared that the nuclear-armed country, which is pivotal to the US war against the Taliban in Afghanistan and against Al-Qaeda, was rapidly succumbing to Islamist extremists.

“The implicit threat - if you don’t do it, we may have to - was always there,” said the Pakistani official. He said that under American pressure, Pakistan’s Inter-Services Intelligence (ISI) agency told the Taliban to withdraw from Buner on Friday.

However, reports yesterday indicated that the Taliban withdrawal was less than total. As a result, hundreds of thousands of people in the district were still at the mercy of armed militants and their restrictive interpretation of Islamic law.

American military and intelligence forces already run limited ground and air operations on Pakistani soil along the border with Afghanistan. But an overt military operation such as that threatened in Swat, away from the border, would mark a major escalation.

The official said last week’s outspoken remarks by Hillary Clinton, the US secretary of state, were “calculated to ramp up the pressure on Pakistan” to take action. Clinton warned that the terrorists’ advance had created a “mortal threat” to world security.

She was one of several American political and military leaders to use unusually strong language about Pakistan’s failure to curb the Taliban. Admiral Mike Mullen, chairman of the joint chiefs of staff, who visited Pakistan, said he was “extremely concerned” about the developments and that the situation was “definitely worse” than two weeks ago.

General David Petraeus, of US Central Command, which oversees Afghanistan - to which America is about to commit 17,000 more troops - said Al-Qaeda and Taliban extremists in Pakistan posed an “ever more serious threat to Pakistan’s very existence”.

These remarks have stung Pakistan. Husain Haqqani, the ambassador to Washington, accused the Obama administration of making it harder for his country to fight the Taliban.

“The US needs to relate its comments to the ground realities in Pakistan instead of the mood in Washington,” he said. “Most Pakistanis are not supportive of the Taliban way of life, but at the same time widespread anti-Americanism confuses many Pakistanis into having a conflicting view.

“We want to turn that view around but the US and its leaders must help us to do that.”

The latest crisis stems from a controversial ceasefire the government signed in February to end months of vicious fighting between the Taliban and the army in Swat that caused significant loss of life and an exodus from what had once been a tourist centre. Some 500,000 now live outside Swat, a third of them in camps that used to shelter refugees from the fighting in Afghanistan.

In return for the imposition of sharia [Islamic law] in Swat, the Taliban agreed to disengage, disarm and stop menacing people. But it was from Swat last week that their fighters overran Buner with about 500 well-armed men under a hardline commander, Maulvi Khalil.

As in Swat, once his forces had established themselves, Khalil began to impose the movement’s repressive rules on what had once been a peaceful valley. He ordered girls over seven to wear veils and directed men to keep their women inside and to grow beards. He banned music. In several villages the Taliban were snatching mobile phones on the pretext that they had musical ring tones or photos of women on them.

The Taliban stole livestock, took vehicles belonging to government officials and ransacked the offices of some local nongovernment organisations. In a phone call, Khalil denied the Taliban were terrorists. He said: “We’ve raised the arms to spread the message of Allah. This is the responsibility of each and every Muslim.” But residents fear it is just a matter of time before their daughters are forced to marry Taliban commanders, a process that has begun already in Swat, along with public floggings.

On Friday, in a much publicised agreement with the government, Khalil agreed to withdraw. Local residents said the withdrawal was incomplete. He had left men behind to supplement local armed Taliban groups and newly recruited sympathisers.

“There is a collective holding of breath,” said Sam Zarifi, Amnesty International’s Asia director, from Islamabad. “The Taliban edicts are still in force and the dismantling of the civilian infrastructure is still very much in effect, so a lot of doctors, midwives, civil servants have left and people are hunkering down because they fear an army operation.”

The government sent a few hundred paramilitaries to Buner last week but they kepta low profile. It has not sent any troops. The Americans want the government to shift troops from the India-Pakistan border to meet the Taliban threat, but frightened residents of Buner fear an army operation would cause civilian casualties.

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