Just when it seemed already frayed Pakistani-American relations couldn't get any worse, the Obama administration's top soldier publicly accused Pakistan's powerful security agency of murdering a journalist who dared to probe the Islamabad government's murky dealings.
After nasty spats over gun-happy CIA agents killing Pakistani pedestrians, the humiliating American attack deep inside Pakistan that killed Osama bin Laden and a long-running duplicitous game over assassination strikes by U.S. Predator drones, the latest sniping takes relations to a new low.
Admiral Mike Mullen's accusation was stunning - not for what he said, the brutal murder of the crusading Pakistani journalist was widely blamed on the nation's notorious and bloodstained Inter-Service Intelligence agents - but because the U.S. chairman of the Joint Chiefs of Staff said it so plainly and publicly.
Syed Saleem Shahzad's disappearance, torture and murder was only the latest in a long series of "accidents" that have befallen those who probed into the dark corners of the ISI.
The torture and murder "was sanctioned by the government," Adm. Mullen told the Pentagon Press Association at an on-the-record luncheon, although he said he had no evidence trail that implicated the ISI. As a veteran Beltway warrior, there can be no doubt Adm. Mullen knew exactly the sort of diplomatic damage his bombshell would cause.
The admiral didn't stop there. He suggested the killing was part of a pattern and added that Pakistan was continuing "to, quite frankly, spiral in the wrong direction."
Not surprising, Pakistan, supposedly America's key ally in the war against violent Islamic extremism in the region, responded with barely suppressed outrage.
Information Minister Firdous Ashiq Awan denounced Adm. Mullen's comments as "extremely irresponsible and unfortunate," adding America's most senior military commander was creating "problems and difficulties for the bilateral relations between Pakistan and America" and would damage the joint campaign against al-Qaeda and Taliban leaders believed hiding in Pakistan.
There is growing disquiet in Washington that it may not be too hard to hide in Pakistan where - it is widely believed - at least some elements of the ISI maintain close links with radical Islamic groups.
That view was reinforced by the U.S. raid that killed al-Qaeda's paramount leader, who had been living comfortably - if not quite openly - in the Pakistani military garrison town of Abbottabad at a compound barely a rifle shot from the nation's elite army officer academy.
Pakistan insisted it had no clue that Mr. bin Laden had been living less than an hour's drive from Islamabad for five years.
After the raid, Islamabad kicked hundreds of U.S. military trainers out of the country, just as it kicked out an unspecified number of covert U.S. intelligence agents after one of them killed a pair of Pakistan citizens in Lahore earlier this year.
Pakistan also halted U.S. drone flights from air bases inside the country - although the missile-firing Predators and Reapers continue to fly from Kandahar in Afghanistan to target Taliban and al-Qaeda suspects.
Adm. Mullen, who steps down this summer after four years and spent much of that time trying to foster and develop a working alliance with Pakistan's military, admits the relationship is a mess. "We've been through a very, very rough time," he said. "We are committed to sustaining that relationship because we think it's vital to the region and, actually, globally. But we recognize that it's under great stress right now."
In Pakistan, anti-American feeling runs high. The drone attacks and rumours of CIA agents and huge convoys of war materiel rolling toward Afghanistan only feed a larger fear.
U.S. President Barack Obama has said he views Afghanistan-Pakistan as a single theatre in the struggle against Islamic terrorism and has pledged to concentrate on what he calls "the right war."
But the President's recent decision to hasten the troop pullout from Afghanistan has rekindled fears in Pakistan that - once again - it will be left to cope with armed radical groups, as happened when the United States abandoned the region after the Soviets were driven out in the late 1980s.
Radical groups have already staged daring attacks on Pakistani military installations - including burning aircraft at an air force base in Karachi and storming the high command's headquarters compound.
Although U.S. officials say they accept the assurance that Pakistan's 100-plus arsenal of nuclear warheads is safe from internal attack or theft, that remains the nightmare scenario.