PESHAWAR, Pakistan (Reuters) - The withdrawal of most combat troops from Afghanistan at the end of 2014 has raised questions from Kabul to Brussels to Washington about the potential chaos that may follow if the Taliban press to take over again.
Few people are as worried about what the pullout could trigger next door in nuclear-armed Pakistan as Lieutenant-General Khalid Rabbani, commander of the frontline corps fighting militants in the northwest of the country.
Sitting in his office in the heavily-fortified headquarters of the XI Corps in Peshawar - one of the Pakistan cities worst hit by suicide bombings - he speaks anxiously about creating the right perceptions as the foreign troop exit approaches.
If the Taliban are seen as the victors in any way, that could be disastrous for Pakistan, emboldening homegrown Taliban militants, who are close to al Qaeda, to step up their campaign to topple the U.S.-backed Islamabad government.
"If they are leaving and giving a notion of success to the Taliban of Afghanistan, this notion of success may have a snowballing effect on to the threat matrix of Afghanistan," Rabbani told Reuters in an interview this week.
"On our side, it may give impetus to the already dying down so-called Tehrik-e-Taliban's (Pakistan Taliban) effort over here."
Rabbani has good reason to worry, even though he and other military officials say security crackdowns have hurt the Pakistani Taliban.
The loose alliance of militant groups - the biggest security threat to the state - has proven resilient, despite repeated offensives from the military, one of the largest in the world.
They have carried out suicide bombings and high-profile attacks, including one on army headquarters, since they were formed in 2007 after a military raid on Islamabad's Red Mosque, which was controlled by its allies.
The Pakistani Taliban have close links with the Afghan Taliban. They move back and forth across the unmarked border, exchange intelligence and shelter each other in a region U.S. President Barack Obama has described as "the most dangerous place in the world".
Those ties worry military commanders like Rabbani, who believe the strengthening of ties between the Pakistani and Afghan Taliban will complicate efforts to contain any spillover of instability in 2014.
One of the most notorious Pakistani Taliban leaders, Afghanistan-based Mullah Fazlullah, has already demonstrated what may be in store if U.S.-led NATO forces fail to stabilise Afghanistan before 2014.
Hundreds of his fighters staged cross-border raids on Pakistani border posts last summer, killing dozens of Pakistani soldiers.
"Our friends on the other side know exactly where they are because we communicate it to them. But they have capacity issues," said Rabbani, referring to Western and Afghan forces.
"I wonder, that if the superpowers and the Western world operating on the other side, they have capacity issues, we certainly have them too."
Critics say Pakistan has created a major security threat along the border by supporting militant groups for decades, an allegation Islamabad denies.
Rabbani took command at a time of deep crisis in relations between Washington and Islamabad, a week after a cross-border NATO air attack killed 24 Pakistan soldiers on November 26.
Pakistan's parliament recently concluded a review of ties with the United States, recommending that the government demand an end to American drone strikes in the nation's tribal areas.
Even though analysts say drone strikes which kill high-profile al Qaeda or Taliban militants are not possible without Pakistani intelligence assistance, the campaign fuels anti-American sentiments.
Rabbani acknowledged the strikes can be effective, but said they also kill civilians and are counterproductive.
"You kill five, and you're making 50 more enemies. It's very clear arithmetic. This is the arithmetic that we're trying to make them understand," he said, adding that instead intelligence should be shared so that Pakistan can act.
"They may indicate (a target), we'll pound it with the precision shooting of our F-16s. So it can be done, it has been done at one or two places. Why can't this model be followed, we keep on telling them this is a possible model to be followed."
Washington has repeatedly urged Pakistan to mount a full-scale assault on North Waziristan and go after the Haqqani network, one of the deadliest Afghan insurgent groups.
The U.S. ambassador to Afghanistan said this week that there was "no question" that the Haqqani network had staged coordinated attacks on Kabul and repeated calls for Pakistan to pursue the group.
Pakistan is a recipient of billions of dollars in U.S. aid. It denies that the Haqqanis are based there and says it is too stretched elsewhere fighting the Taliban.
Rabbani said the region near the Afghan border was a major security risk, but repeated the official line that Pakistan will set its own timetable for any operation in the area.
"Something has to be done with North Waziristan. The sooner the better. And we are already looking into it as to how we are going to deal with it," he said.
"We will have our own time and decision to go."
Writing by Michael Georgy; Editing by Ron Popeski