ISLAMABAD: The Pakistani Taliban's brazen attack on a major air force base near the capital underscores the need for the Pakistani army's planned offensive against the group in its last major sanctuary along the Afghan border. 

But the operation in the remote, mountainous North Waziristan tribal area is fraught with danger, both in terms of battling the Taliban and avoiding combat with other militants who are not viewed by the state as a threat because they have focused their attacks on Nato and Afghan forces inside neighbouring Afghanistan.

The United States has repeatedly pressed Pakistan to attack this latter group of militants in North Waziristan, especially the so-called Haqqani network. But the offensive is likely to disappoint on that front and is shaping up to be much less dramatic than the type Washington has long wanted.

The major perceived threat for Islamabad is definitely the Taliban's Pakistani branch, which has waged a bloody insurgency in the country for years that has killed over 30,000 people.

A team of nine Taliban militants armed with assault rifles and rocket-propelled grenades attacked a Pakistani air force base near Islamabad with possible links to the country's nuclear program before dawn Thursday, killing two security officials. Security forces managed to retake the base after two hours of heavy fighting in which all nine militants were killed.

Asad Munir, a retired army brigadier who served as an intelligence officer in Pakistan's tribal region, said the attack reinforced the need for an operation against the Pakistani Taliban in North Waziristan.

''They should not be allowed to have any territory under their control,'' said Munir. ''That enhances their ability to plan and send people to attack.''

Pakistan long refused US demands to launch an offensive in North Waziristan, saying its forces were stretched too thin by fighting in other parts of the tribal region.

Many analysts believe Pakistan's stance was also driven by its reluctance to upset the Afghan Haqqani network, because of its historical ties to the group and the possibility that the Haqqanis could be a useful ally in Afghanistan after foreign forces withdraw.

But North Waziristan — the only part of the tribal region where the army has not carried out an offensive — has become an increasing problem for Pakistan as the Taliban and their allies, including al Qaeda and other foreign fighters, have migrated there to escape fighting elsewhere.

Mahmood Shah, a retired Pakistani army brigadier and former head of security in the tribal region, said intelligence briefings indicate more than 5,000 militants are based in North Waziristan, 3,000 of whom are enemies of the Pakistani state.

US Defense Secretary Leon Panetta told The Associated Press this week that Pakistan has informed US military officials that it plans to launch an operation against the Pakistani Taliban in North Waziristan in the ''near future.''

Reports of possible offensives in North Waziristan have arisen in the past without action, but Panetta said he was more confident this time.

''They've talked about it for a long time. Frankly, I'd lost hope that they were going do anything about it. But it does appear that they in fact are going to take that step,'' Panetta said.

The top US commander in the region, Gen James Mattis, met with Pakistani army chief Gen Ashfaq Parvez Kayani and other senior officials in the country Thursday. It's unclear if they discussed the North Waziristan operation.

Pakistani military officials downplayed Panetta's comments, with one saying ''you will see a slow ratcheting up over many months, even a year,'' not a swift, sweeping campaign as implied by the defense secretary.

Pakistani Army Chief Gen Ashfaq Parvez Kayani seemed to rally public support for the new push in speech on the country's independence day Tuesday.

''The fight against extremism and terrorism is not just the army's, but the whole nation's,'' said Kayani.

The crackdown in North Waziristan started in recent months as the army increased its forces in the area, said a Pakistani military official, speaking on condition of anonymity because he was not authorised to discuss the plan publicly.

But local residents said they haven't seen any unusual military activity.

''We have been seeing these media reports of an operation since 2010,'' said Safeer Ullah Dawar, a resident in Mir Ali, one of North Waziristan's main towns and a key area for the Pakistani Taliban and their allies.

''Why should I worry when I know there is no unusual movement of security forces?''

Pakistan has long had more than 30,000 troops stationed in North Waziristan, but their operations have been limited.

The army boosted that force over the past three months by adding an additional brigade — about 4,000 soldiers —  and plans to add another in the coming months, said the Pakistani military official.

"Some minor operations are happening, but I believe it's going to disappoint the West completely because it has nothing to do with the Haqqani network," said Moeed Yusuf, the South Asia adviser at the United States Institute of Peace.

The US would welcome action against the Pakistani Taliban and their allies, especially al Qaeda, because they do pose a threat. The Pakistani Taliban were linked to a suicide attack in Afghanistan in 2009 that killed seven CIA employees and a failed car bombing in New York's Times Square in 2010.

But the US has been intensely focused on the Haqqani network.

Washington views the group as one of the most dangerous fighting in Afghanistan, partly because of its record of carrying out high-profile attacks in Kabul.

Any Pakistani operation in North Waziristan would likely be coordinated with the Haqqani network to avoid drawing them into the fight, said Pakistani analysts and retired military officers.

The army would also likely negotiate with Hafiz Gul Bahadur, the most powerful local warlord in North Waziristan, who has also focused on fighting inside Afghanistan.

He is widely believed to have a nonaggression pact with the army, an accord which the generals have never officially acknowledged. But he has also clashed with the army in the past and could feel threatened by operations on his home turf.

Mansur Mahsud, director of administration and research at the Islamabad-based Fata Research Center, believes Pakistan can successfully carry out a targeted operation against the Pakistani Taliban and their allies without drawing in the Haqqanis or Bahadur.

"If Pakistan says 'I'm going to target only those groups that are targeting me,' then I don't think they would be foolish enough to fight against Pakistan because it would weaken them a lot," said Mahsud.

Pakistan would be helped somewhat by geography. Most of the Pakistani Taliban militants and their allies are based in and around Mir Ali. Many of the fighters loyal to the Haqqani network and Bahadur are in and around Miran Shah, a town about six miles away, said Mahsud.

But there is some geographic overlap, and the groups have common allies. Both the Pakistani Taliban and the Haqqani network are closely aligned with al Qaeda and other foreign fighters.

"I don't think the operation will be feasible beyond a point because they do coexist geographically, and the army doesn't want to force Haqqani's hand into saving the Pakistani Taliban," said Yusuf, the South Asia expert.

"But I think they will do enough against the Arabs, Uzbeks and other foreign fighters and some Pakistani Taliban just to show they have done something there."