Bin Laden's death leaves prime minister facing tough questions despite American reassurance over Pakistan's cooperation
Pakistan's relations with the US had already touched their lowest point since 2001 amid a flurry of spy scandals, media accusations and unprecedented Pakistani anger against CIA drone strikes.
But the discovery and death of Osama bin Laden, the fugitive Islamist who started it all, near a military facility just two hours from Islamabad, pushes the edgy allies into uncharted – and possibly dangerous – waters.
In public yesterday, the two governments paid each other polite compliments. President Barack Obama noted "our counterterrorism cooperation with Pakistan"; in Islamabad prime minister Yousaf Raza Gilani hailed the attack as a "great victory". But behind closed doors, there was a sense that Bin Laden's death could permanently reshape relations between the two countries.
"This is a game changer," said one western diplomat in Islamabad. "But it's very hard to tell what the new game will be."
Prominent Pakistani opposition figures seized on the American assault as an example of the government's subservience to Uncle Sam. "This whole war was for Osama. So now they should leave us alone and let us live in peace," demanded Imran Khan, the cricketer-turned-politician.
Meanwhile the former President Pervez Musharraf – who, while in power, allowed the first drone strikes inside Pakistan in 2004 – protested at "a violation of our sovereignty".
There was also pressure from across the border in Afghanistan where President Hamid Karzai hinted that the Pakistani state itself was complicit in sheltering Bin Laden who had "hidden himself in the military bases of Abbottabad".
The killing revived several questions about alleged links between al-Qaida and elements within Pakistan's security forces.
The military has arrested numerous senior al-Qaida figures over the past decades, but always insisted that Bin Laden was not present there, often deflecting blame on Afghanistan.
Yesterday the army found itself in the uncomfortable position of claiming that it had no forewarning of the assault on Bin Laden – and that its own spies had failed to detect his presence in a major military town. "It was a failure on our part," said a senior ISI official. "Unfortunate, but that's a fact."
Only 10 days earlier Pakistan's army chief addressed cadets at the Abbottabad military academy – the equivalent of Sandhurst in Britain or West Point in the US – claiming the army had broken the back of militants linked to al-Qaida and the Taliban.
Now the army is coming under fresh attack from American security hawks. "I think the Pakistani army and intelligence have a lot of questions to answer given the location, the length of time and the apparent fact that this facility was actually built for Bin Laden," said the US Senate Armed Services Committee chairman Carl Levin.
Inside Pakistan, though, things look very different. Coverage on the influential, and often right-wing, television stations yesterday focused on the issue of sovereignty. The army is expected to face more tough questions about what role, if any, the government played in the raid.
But there was little media scrutiny of whether the country's powerful military had, indeed, offered support to Bin Laden. "There are answers to those questions," said liberal commentator Najam Sethi, "but they are not easy answers."
In Kabul, Karzai seized on the news to criticise the US-led coalition for concentrating on counter-insurgency in Afghanistan instead of Pakistan. "This proves that Afghanistan was right," he said. Aminuddin Muzafary, secretary of the High Peace Council, said Bin Laden's death "removed the curtain from Pakistan's face".
Steve Coll, author of several books on Bin Laden, said it stretched credulity to suggest a building on that scale could have been built and occupied by Bin Laden without the attention of anyone in the Pakistan army.
"The initial circumstantial evidence suggests that the opposite is more likely – that Bin Laden was effectively being housed under Pakistani state control," he wrote on the New Yorker website.
Last year, shortly after he was sacked by Karzai, Amrullah Saleh, the former Afghan intelligence chief, claimed the ISI knew exactly where the al-Qaida leader was hiding. Pakistan deliberately kept Bin Laden safe so that the west would ignore its nuclear programme, he told the Guardian.
In London the Pakistani high commissioner, Wajid Shamsul Hasan, insisted that Islamabad had no idea of Bin Laden's whereabouts until the US operation. "Nobody knew that Osama bin Laden was there – no security agency, no Pakistani authorities knew about it," Hasan told BBC Radio 5 Live.
"The fact is that the Americans knew it and they carried out the operation themselves and they killed Osama bin Laden and then later our president of Pakistan was informed that the operation was successful, and that's it."
But the chairman of parliament's foreign affairs committee Richard Ottaway said: "Unfortunately, I am not sure that the government of Pakistan speaks for the whole of Pakistan. It is a divided country with lots of tribal loyalties, and there are clearly internal divisions within Pakistan's security services."