There's an uncomfortable mystery behind Osama bin Laden living in Pakistan for 5 years

When the US found Osama bin Laden found hiding in a walled compound less than a mile from Pakistan's elite military academy, questions arose about what the country's intelligence agency (ISI) knew about the world's most wanted terrorist hiding in its own backyard.

Journalist Seymour Hersh recently wrote that the US Navy SEAL raid was not unilateral as reported. Instead, Hersh asserts, the mission was fully backed by Pakistan's army commander and the head of the ISI after the US threatened to expose that the ISI had been sheltering bin Laden for at least five years.

Journalists and experts disputed much of Hersh's thinly sourced account. Husain Haqqani, Pakistan's ambassador to the US at the time of the May 2011 raid, subsequently wrote that Hersh's claims regarding Pakistan's role in and knowledge of the raid "simply do not add up."

What did Pakistan know?

In any case, a wealth of information has been uncovered in recent years pointing to ISI complicity in harboring bin Laden, even as the Obama administration's interest in demanding answers from the Pakistani government waned rather quickly in the months following the successful raid.

Pete Souza/White House/ReutersPresident Barack Obama (2nd L) and Vice President Joe Biden (L), along with members of the national security team, receive an update on the mission against Osama bin Laden in the Situation Room of the White House, May 1, 2011.

Among the information pointing to ISI knowledge of bin Laden's whereabouts:

• In March 2014, New York Times correspondent Carlotta Gall wrote that a Pakistani official told her that the US "had direct evidence that the ISI chief, Lt. Gen. Ahmed Shuja Pasha, knew of Bin Laden's presence in Abbottabad."Gall recently wrote that she "learned from a high-level member of the Pakistani intelligence service that the ISI had been hiding bin Laden and ran a desk specifically to handle him as an intelligence asset."

• A cell phone found during the raid belonging to bin Laden's most-trusted courier contained contacts to Harakat-ul-Mujahedeen, a militant group and longtime asset to the ISI that had been allowed to operate in Pakistan for at least 20 years, the Times reported in 2011.
• Gall reported that handwritten notes, letters, and computer files collected from bin Laden's compound during the raid "revealed regular correspondence" between bin Laden and militant leaders who were closely protected by, and loyal to, the ISI.
• Bin Laden's compound was not inconspicuous: It was a mansion that locals found "strange," Pakistan's former civilian intelligence chief told Gall. Intelligence officials would have searched it, if they had wanted to - especially given its proximity to the military academy.

The Pakistani government has staunchly denied that they even knew bin Laden was hiding in the Abbottabad compound, let alone that he was being protected by the ISI.

REUTERS/Mian KhursheedSecretary of State Hillary Clinton (4th L) meet Pakistan's Prime Minister Yusuf Raza Gilani (C) at the prime minister's residence in Islamabad on October 20, 2011.

Still, many have raised doubts about the plausibility of Pakistan's claims. And the country looks bad either way.

"If Bin Laden's presence was not known to Pakistan's security agencies when he was located so close to important military installation, it will be viewed as their incompetence or overconfidence," Hasan Askari Rizvi, a military analyst in Lahore, told the New York Times in 2011."If they knew about his presence but did not take action, this will raise questions about the agenda of Pakistan's security agencies for fighting terrorism," he added.

Bin Laden's support system

John O. Brennan, Obama's chief counterterrorism adviser at the time of the raid, described it as "inconceivable" that Bin Laden "did not have a support system in the country that allowed him to remain there for an extended period of time."

According to Haqqani, the former Pakistani ambassador, the key question after the raid was to determine whether bin Laden's support system near Pakistan's version of West Point Military Academy lay "within the government and the state of Pakistan or within the society of Pakistan."

Department of DefenseAn aerial view shows the compound where Osama bin Laden was killed, in Abbottabad, Pakistan.

The possibility that the ISI provided bin Laden with this "support system" is plausible given the agency's 30-year-old strategy of protecting militant groups and using them as intelligence assets and proxy forces to gain leverage over extremists in Afghanistan.

Gall reported that compounds and safe houses much like bin Laden's Abbottabad "home" are frequently used by the ISI for interrogations, "enforced seclusions," and protective custody for leaders of banned military groups. Police officers would then be warned to back off if they try to search the houses or undermine an intelligence operation.

What does the US know?

Haqqani concedes that someone in Pakistan clearly protected bin Laden from 2006 to 2011. While denying that the ISI knew bin Laden's whereabouts, Haqqani concludes that "the failure of both Washington and Islamabad to disclose a more complete understanding of what transpired in the years leading up to the raid" led to conspiratorial stories like Hersh's.All in all, an uncomfortable mystery remains about how much Islamabad knew - and why the US never explained who harbored Osama bin Laden in Pakistan.Haqqani, for his part, thinks we may never fully know because it "might not be in either Islamabad's or Washington's interest to wake sleeping dogs."

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