High in the mountains, a nation’s troops are regularly attacked by insurgents who easily come and go from sanctuaries across a porous international border. Armed forces in the neighboring country, nominally an ally, do little to stop the rebels. Resentment in the capital is growing.

For several years, that is how frustrated U.S. officials have described the challenge for the NATO coalition in Afghanistan, which they say is battling Taliban enemies who operate freely from hilly hideouts in next-door Pakistan, an American ally and aid recipient.

But in the past several months, Pakistan has turned the tables, adopting a mirror-image argument in its own defense.

According to this increasingly assertive account, Pakistani Taliban fighters flushed out by Pakistani military offensives have now settled into a security vacuum created by NATO forces in eastern Afghanistan whose attention is focused elsewhere. That territory, Pakistan contends, is the new regional hub for Islamist militants of all stripes, one that the U.S.-led coalition must better control to prevent attacks on American forces as well as strikes inside Pakistan.

Some analysts here say Pakistan is now pushing this case as an excuse for not pursuing the Haqqani network, an Afghan Taliban faction that U.S. officials assert operates unmolested from Pakistan. Others say the opposite: that the Americans are boosting pressure on Pakistan by allowing the attacks inside Pakistan.

Either way, the dueling narratives have become the latest illustration of the disconnect between Washington and Islamabad, and they help explain why the ever-prickly security partnership has plummeted to such lows that U.S. Secretary of State Hillary Rodham Clinton arrived in Islamabad on Thursday night with an extraordinarily high-level American delegation that included CIA director David Petraeus.

The disconnect, which also involves differences over negotiations and the U.S. troop drawdown in Afghanistan, was on center stage during a stopover by Clinton in Kabul, where she sternly warned Pakistan that it would face dire consequences if it failed to eliminate militant sanctuaries on its soil. In Pakistan, talk show pundits encouraged Pakistani officials to take an equally hard line with the Americans by insisting they show appreciation for the nation’s help, not condemnation.

In an interview, a Pakistani intelligence official said Pakistani leaders expected to be confronted with evidence of state support for the Haqqanis and threats of aid cuts. But the official, who spoke on the condition of anonymity, said “many in our security establishment” had decided that the real U.S. target is Pakistan’s nuclear arsenal, and that Pakistan will offer little help unless the United States limits the role of India, Pakistan’s prime rival, in Afghanistan.

“Any breakthrough is unlikely in the talks,” said the official, who spoke on the condition of anonymity.

Pakistan had already escalated its complaints this week, faulting NATO forces for failing to hunt down an infamous militant cleric whom Pakistani troops expelled from its Swat Valley in 2009. Pakistani military spokesman Maj. Gen. Athar Abbas told Reuters that Maulvi Fazlullah is now in Afghanistan. From there, Abbas said, Fazlullah has directed a series of recent cross-border strikes that have killed more than 100 Pakistani security forces. The U.S.-led coalition has ignored Pakistan’s pleas for action, he said.

“The problem refuses to go away,” Abbas said.

Tensions over the remote Afghanistan-Pakistan frontier area have simmered for months amid reports of cross-border attacks. U.S. and Afghan officials complain of steady rocket fire emanating from Pakistan. Pakistan says its soldiers have been besieged by militant armies from Afghanistan. Both sides accuse the other of inadequately patrolling the frontier.

The issue surfaced again this week as NATO launched a new offensive against the Haqqani network, which U.S. officials have said is aided by Pakistani intelligence. Those accusations infuriated Pakistan, and its leaders and news media have drummed up a public frenzy over the potential for a U.S. invasion, though there is no evidence one is likely.

In recent days, Pakistani newspapers have splashed alarmist headlines about NATO troops massing along the Afghan side of the border. Though Pakistan has previously encouraged such a move to assist with border security and U.S. military officials said it was notified about the offensive, suspicion swirled in Pakistan that it is a sign of an American march to war.

In a closed-door briefing Tuesday, Pakistani army chief Gen. Ashfaq Kayani told lawmakers the possibility of an invasion was remote because the United States would “think 10 times” before invading a nuclear power such as Pakistan, according to various news reports. But he also said a Pakistani operation against the Haqqanis would accomplish little.

“The problem is in Afghanistan, not Pakistan,” Kayani was quoted as saying.

U.S. officials have said they would not pursue the Haqqanis in unilateral ground raids inside Pakistan. But the CIA has increased drone strikes near Miram Shah in North Waziristan, which American officials say is the Haqqani network’s stronghold. The strikes are extremely unpopular in Pakistan.

Disagreement over the Haqqanis is only the latest friction point in the bilateral relationship, which both sides say is warming despite the heated public rhetoric. Even so, many here say Pakistani officials are likely to turn one of the most despised Washington arguments back on Clinton.

“From the day the Twin Towers fell on 9/11, the same mantra has been endlessly repeated to Pakistan: It must ‘do more’ in the fight against terrorism,” the editorial board of the Express-Tribune wrote Wednesday. “Finally we have the opportunity to say the same thing to the U.S.”

Special correspondent Shaiq Hussain contributed to this report from Islamabad.