Is it possible that, more than eight years after the terror attacks on America, the Pakistani army is finally closing in on Osama bin Laden?

The wild and lawless mountains of South Waziristan have resisted control and policing for well over a century. In the late 19th century, Mullah Powindah, known as "the wandering cleric", became the British Raj's fiercest enemy in these vast, arid mountains. Successive punitive operations and peace deals failed to tame him.

Schooled at a madrassa in the northwest, Powindah was the first religious leader of the area with political ambitions. He killed local tribal elders, rallied his men to wage "jihad", and even assum­ed the title of "king" (badshah) of the taliban. He was never killed or captured and the frontier he and his men haunted remained impregnable until well beyond the end of the British Raj.

But perhaps that is finally changing, thanks to a mixture of ferocious American arm-twisting, a belated Pakistani recognition of its own self-interest and the awesome (and much resented) new technology of the Predator drone.

In August, a CIA-operated Predator drone stuck down Baitullah Mehsud, the notorious Taliban commander. Despite the bitter criticism such strikes evoke among ordinary Pakistanis, they have succeeded where all previous assaults have failed.

It is widely believed the barren and forbidding mountains of Pakistan's tribal areas have been home to the core of al-Qaida ever since bin Laden fled after the American bombing of Tora Bora in 2001.

Senior western diplomats believe they are still there. But huge rewards have gone uncollected and no hard intelligence has emerg­ed, to the huge frustration of the United States.

Hillary Clinton was undiplomatic enough to bring that failure up this week, repeating the charge when she told a Pakistani interviewer: "This is a big government... Somebody, somewhere in Pakistan must know where these people are."

But this weekend the interior minister Rehman Malik shot back: "There was a time when the world was telling us to do more. We have decided to fight back."

On the frontline, as artillery fire boomed across the Sherwangai valley, military commanders exuded confidence. "We are doing a hardcore job fighting the terrorists," said major general Khalid Rabbani, on top of a rocky hill. The expansive view around offered a rare look at the arid borderlands long suspected to serve as sanctuaries to the Pakistani Taliban and al-Qaida­'s­ senior leadership.

"They have given a good fight," added Rabbani, but now many are being killed and others are going deeper into the territory." It was impossible to confirm these details independently.

The stiffest challenge lies further ahead, in what the military's chief spokesman major general Athar Abbas called the "triangle of militancy". The army claimed soldiers had mounted the hills around Sara Rogha, one of three notorious Taliban strongholds. The clashes brought the estimated death toll to 289 militants and 34 soldiers.

The drones have been raining down on these mountains for so long that if bin Laden was here he is surely long gone. Many in Pakistan believe he is long dead. Even clues suggesting al-Qaida terrorists were here recently, such as the German and Spanish passports linked to the alleged al-Qaida members involved in the 11 September attacks, may mean less than meets the eye. How long have they been here? How did they get here? Nobody is saying.

Whatever other secrets this frontier surrenders, holding it will be a more formidable challenge than seizing it. And for that, Predator drones will be of little use.