US frustrations over Pakistan boil over
Adm Mike Mullen's comments that the militant Haqqani group is a "veritable arm" of Pakistani intelligence service the ISI is just the latest and most extreme in a series of statements that will be seen in Pakistan as incendiary.
Not only will this generate concern in government circles, but the wider public will also be very worried about the implications of this war of words.
Pakistani media coverage of a string of outspoken comments from the US on Pakistani relations with militants have reflected these fears. People are worried that the Afghan war is coming to their side of the border.
All of a sudden the Americans are talking openly about suspicions they have harboured for years and at an extremely senior level.
For years, US statements have trod delicately about the issue. They have talked about "elements" of the Pakistani "establishment" having "links" with militant groups.
The new accusatory terminology is instructive and lays bare the gulf that has opened up between these uneasy allies.
The question is what will it really achieve in Pakistan and what options are open to the Pakistani government?
The first position, as is clear from past experience, is denial. Pakistan denies the allegations and this has been a consistent position over the years. Interior Minister Rehman Malik has demanded evidence.
"We demand that US provide us proof that the Haqqani network is based in tribal areas, so that we can eliminate our common enemy," he told the BBC.
He also says that while there are militants in the tribal areas, the responsibility for attacks on Afghanistan also lies in what he calls "some weakness on the other side of the border".
The government will be keen to remind the wider world that Pakistan too has been in the grip of terror for years as militants launch deadly attacks across the country.
But many argue that one simply has to look at the number of militants arrested or killed on Pakistani soil. Most famously, Osama Bin Laden was killed in Abbottabad, but countless other high profile Taliban and al-Qaeda leaders have been arrested or killed in the country. The Pakistanis may well issue denials, but analysts will point to such history.
The Haqqani network - and Pakistan's alleged relationship with it - has been a source of frustration for the US.
It is a matter of record that Jalaluddin Haqqani, the leader of the network, was nurtured by the Pakistani secret service while fighting the Soviets in Afghanistan during the 1980s. Indeed he was also assisted by the CIA.
Some analysts believe the links between the militants and Pakistan's intelligence are still alive. But others say that Pakistan's secret service no longer has control over the potent militant groups it helped create.
There is some evidence, locals in Pakistan's tribal areas close to the Afghan border say, of cross-border support, such as food supplies being provided to militants. Some analysts even allege that elements of the army admit assistance in Waziristan.
But this is flatly denied by Pakistan's military and the ISI, through its various channels, has also denied such links.
What is clear is that the Haqqanis play a significant role in the militant affairs of Pakistan's north-west. They are the "diplomatic glue" of the various militant groups in the area, mediating when there are tensions between competing clans and tribes in Waziristan.
The real question, for most analysts in Pakistan, is not whether the Haqqanis are here or whether the Pakistan military supports them, but what the Americans are going to do now.
They will want Pakistan to go after the Haqqanis, but the Pakistanis are reluctant to undertake a military operation, particularly one that will prove unpopular in a country bruised by the latest US comments and unilateral actions such as the killing of Osama Bin Laden.
And the last Pakistani offensive against militants in Waziristan simply shifted many militants to neighbouring regions.
If there are links, they have so far eluded mapping and conclusive proof. It is now up to the Americans to show if there is a smoking gun.