WASHINGTON (Reuters) - Five days after Afghan militants showered the U.S. embassy in Kabul last September with rockets and bullets in a bold, nearly 20-hour assault, top U.S. officials pointedly pressed the Pakistani government to take action against the Haqqani network, the Taliban-allied militant group.
A handful of American officials, including Secretary of State Hillary Clinton and Marc Grossman, President Barack Obama's envoy for Afghanistan and Pakistan, laid out during the meeting in New York what they knew about the attack, which they traced back to the town of Miranshah, where the network has a base in northwest Pakistan.
The Americans walked away from the 3-1/2 hour encounter much as they have from many others that preceded and have followed it - with Pakistani promises to support U.S. goals but little else.
Now, as the United States and other NATO nations prepare to withdraw from Afghanistan and their time grows short to cripple a still-potent insurgency, debate is raging within the Obama administration about how to confront the threat posed by Haqqani militants - and about how actively Pakistan is supporting them.
"There are troubling links between elements of the Pakistani government and the Haqqanis," said one U.S. official, speaking on condition of anonymity. "How high those links go is an open question."
The September 18, 2011 meeting, on the margins of the U.N. General Assembly, was an important moment in the Obama administration's nearly four-year-long bid to persuade Pakistan to take decisive action against the Haqqanis. The group's tenacious guerrilla tactics - more than those of the rest of the Afghan Taliban - may represent the future Afghan insurgency.
Whether or not the United States can convince Pakistan to act may help determine the legacy of the war in Afghanistan, which began in 2001. With most American troops due to be out of Afghanistan in 2014, the United States appears to have limited options to confront the Haqqanis.
"The Haqqanis are currently the strongest horse in the race ... for influence in a post-U.S. Afghanistan. The Pakistani security services plan to ride that horse as far as it will take them," said Jeffrey Dressler of the Institute for the Study of War think tank, a leading U.S. scholar on the Haqqani network.
The Haqqani network, founded by Jalaluddin Haqqani, fought the Soviet occupation of Afghanistan in the 1980s, with varying levels of support from Pakistani, Saudi and U.S. officials. His son Sirajuddin Haqqani now plays an increasingly prominent role in a network that operates both in Pakistan and Afghanistan.
Influential U.S. congressman Charlie Wilson once called Jalaluddin Haqqani, in his days as a U.S. ally against Moscow in the 1980s, "goodness personified."
"They went from 'goodness personified' to terrorists," said former CIA operations officer Arturo Munoz.
Dressler said current and retired elements of Pakistani security forces, including the powerful Inter-Services Intelligence (ISI), at times gave the Haqqani network financial, logistical and possibly more direct support. Occasionally, he said, they help them plan or carry out attacks.
Some current and former U.S. officials say that a handful of sophisticated attacks by the Haqqani network have shown direct support from elements of Pakistani intelligence, including a 2008 suicide attack on the Indian embassy in Kabul. Some U.S. officials believe such links were evident in the 2011 assault on the U.S. embassy in Kabul but other American officials disagree.
Pakistan vehemently denies such links and points out that thousands of its own soldiers have died battling militants.
U.S. officials assert that Pakistan, riven by tensions between weak elected leaders and a powerful military, has allowed the Haqqani network to fester. Beyond that, U.S. officials say the picture of the relationship between the ISI and Haqqani militants becomes more murky.
"The longer this case goes on, it is impossible to say that there is not a large degree of (Pakistani government) complicity, if not overt assistance, to the Haqqani network," a senior U.S. intelligence source said on condition of anonymity.
Speaking in the September 2011 New York meeting, Pakistani Foreign Minister Hina Rabbani Khar repeated her government's long-standing denials of institutional support from the ISI for Haqqani militants, Reuters has learned. Show us the evidence of such links, she said, and Pakistan will act on it.
Jalaluddin Haqqani made his name as a revered anti-Soviet commander in the area of southeast Afghanistan known as "Loya Paktia," seen by the Haqqanis as their rightful homeland. The United States and Gulf nations also supported Haqqani indirectly as they funnelled money and weapons to the Afghans rebels' fight.
A counterpart to Mullah Omar, the one-eyed Muslim cleric who became the Taliban leader, Haqqani in 1995 joined the Taliban, which went on to rule Afghanistan until being ousted in 2001 in the U.S.-led invasion. Eventually named a minister, he stayed on the margins of Taliban decision-making as it fought to impose a hard-line version of Islam before 2001 and, later, expel foreign troops.
Some experts say the Haqqani group appears to have evolved beyond the goal of controlling its Afghan homeland, embracing more ambitious aspirations closer to those of al Qaeda. That shift has taken place as Sirajuddin, who grew up around foreign militants who flocked to the region, has gained prominence.
For years, the Haqqanis and the Taliban barely registered as a major military threat for most U.S. officials, as the United States under former President George W. Bush sought to limit the degree of U.S. military involvement in Afghanistan to focus on Iraq, which U.S.-led forces invaded in 2003.
Attacks by the Taliban and its allies began to pick up in 2006 and increased sharply in 2008. Over time, attacks by Haqqani insurgents showed increasing military sophistication.
The Haqqani insurgents have been blamed for some of the most daring, complex attacks in Afghanistan, including a 2011 truck bombing in Wardak province, a 2008 attack on a Kabul parade ground where Afghan President Hamid Karzai was present, and major assaults on Kabul's most important hotels.
After the suicide bombing on the Indian embassy, which killed nearly 60 people, U.S. officials said they intercepted telephone calls between militants carrying out the attack and individuals in Pakistan associated with the ISI.
Some intelligence sources say cell phones or testimony collected after the 2011 U.S. embassy attack also point back to individuals in Pakistan linked to the ISI. That assertion is rejected by Pakistan and is disputed by some U.S. officials.
The extent of disagreement within the Obama administration about such links was evident days after Clinton's meeting in New York. Admiral Mike Mullen, speaking to Congress just before he retired as the top U.S. military officer, described the Haqqani network as a "veritable arm" of the ISI.
Mullen, incensed that such attacks continued despite his long effort to court Pakistani Army chief General Ashfaq Kayani, also suggested the ISI supported the group as it launched the U.S. embassy assault and similar high-profile attacks.
The testimony not only triggered heated denials from Pakistan but angered officials in the White House and State Department, who believed the evidence was not so clear.
Reviewing Mullen's testimony in advance, the State Department had urged the Pentagon to delete some of the stronger accusations against Pakistan. It did not do so.
"He went too far," another U.S. official said of the exchange, which has not previously been reported.
Mullen has since stood by what he said. And many in the military cheered his parting shot.
"They're killing our people," a third U.S. official said, also speaking on condition of anonymity. "They're able to do that to some degree because they're allowed to have safe havens ... and in some cases given tacit support."
The debate over the Haqqani network also manifests itself in tensions between the State Department, Congress and the Pentagon over whether it should be officially listed as a "terrorist" group by the United States.
The State Department, leading a push for a peace deal between the Afghan government and the Taliban, has resisted pressure to list the group. U.S. diplomats appear to be hoping the Haqqanis can be part of a deal - if one is possible.
Last summer, U.S. negotiators met with Ibrahim Haqqani, Jalaluddin's brother, in an encounter brokered by Pakistan. Such contacts could make a terrorist listing awkward.
The United States has pressed Pakistan to mount a military offensive targeting the network. Pakistani officials have expressed uncertainty about how well their forces would fare against a group entrenched and well-armed in North Waziristan.
Robert Grenier, a former senior U.S. intelligence official who was CIA station chief in Pakistan until 2002, said the Haqqanis could create major problems for Pakistan's government.
"It's not just a client-master relationship," Grenier said.
Clinton, during an October 2011 visit to Islamabad, said Pakistan's own security was at risk. "You can't keep snakes in your backyard and expect them only to bite your neighbors," she said. "Eventually, those snakes are going to turn.
The United States also has sought to use millions of dollars in civilian and military aid to Pakistan as leverage, to little avail. That leverage might disappear if Congress follows through with moves to cut aid, the latest in a series of bilateral crises including the killing of 24 Pakistani soldiers last November in a U.S. air attack along the Afghan border.
The United States has continued a campaign of drone strikes in North Waziristan that has accelerated in recent weeks. It also has taken steps to target the group's financing.
While U.S. military commanders have expressed concern about a simmering threat in areas of eastern Afghanistan that are home to Haqqani militants, there are no current plans to shift the bulk of remaining foreign troops there. That means much of the fight would fall to the inexperienced Afghan army in those areas.
U.S. officials should keep in mind that Pakistan is already looking past the departure of most U.S. troops, said Jonah Blank, a foreign policy expert at the RAND Corp. research group.
"We are asking them to turn against an outfit they consider a valuable asset - and make an enemy out of a group that will be in the region forever," Blank said.
Editing by Warren Strobel and Will Dunham