When Pakistan’s Army finally launched its attack on the tribal region of South Waziristan this month, its target was the Pakistani Taleban, whom it blamed for a series of suicide bombings and other attacks in the country.

But less than two weeks on, the offensive is already revealing the extent to which the Pakistani militants are intertwined with al-Qaeda in an alliance that poses arguably a greater threat to the West than the Afghan Taleban.

The German passport that the army said it found in a mud compound in South Waziristan suggests that Said Bahaji, its owner and a senior al-Qaeda leader, has recently been fighting alongside the Pakistani Taleban.

It also provides rare evidence of the movements of one of the alleged conspirators in the September 11 attacks, showing that he arrived in Karachi from Istanbul on September 4, 2001. Pakistani leaders will hail the discovery as evidence that they are complying with repeated US requests to act against not only the Pakistani Taleban, but al-Qaeda and other militants.

Some US officials will also take the discovery as evidence that the Pakistani Army is becoming more serious about tackling the foreign militants who have been sheltering in the tribal areas since fleeing Afghanistan in 2001.

However, the finding also raises some troubling questions for the US as President Obama prepares to make a decision in the next two or three weeks on how best to tackle the militants in Afghanistan and Pakistan.

An increasing number of US officials argue in favour of negotiating a truce with the Taleban, many of whom they say are “moderates” who will switch sides quickly if provided with the right incentives.

That may be true in much of Afghanistan, where people often fight for the Taleban out of necessity. But it does not appear to be the case in South Waziristan, where al-Qaeda leaders have lived alongside local and foreign militants for the past eight years, providing them with funding, training and ideological indoctrination.

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