The idea that 9/11 was an inside job got circulation through the "documentary" series Loose Change, described as the "first internet blockbuster". A recent filing at The Gray Zone, "Bombshell filing: 9/11 hijackers were CIA recruits," searches for embarrassing facts obscured by years–decades, now–of speculation and conspiracy theories. The capacious CIA term "blowback," referring to the unintended consequences of intelligence operations, comes to mind.
"A newly-released court filing raises grave questions about the relationship between Alec Station, a CIA unit set up to track Al Qaeda chief Osama bin Laden and his associates, and two 9/11 hijackers leading up to the attacks, which was subject to a coverup at the highest levels of the FBI.
Obtained by SpyTalk, the filing is a 21-page declaration by Don Canestraro, a lead investigator for the Office of Military Commissions, the legal body overseeing the cases of 9/11 defendants. It summarizes classified government discovery disclosures, and private interviews he conducted with anonymous high-ranking CIA and FBI officials. Many agents who spoke to Canestraro headed up Operation Encore, the Bureau's aborted, long-running probe into Saudi government connections to the 9/11 attack.
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A Bureau special agent, dubbed "CS-3" in the document, stated Bayoumi's contact with the hijackers and support thereafter "was done at the behest of the CIA through the Saudi intelligence service." Alec Station's explicit purpose was to "recruit Al-Hazmi and Al-Mihdhar via a liaison relationship", with the assistance of Riyadh's General Intelligence Directorate."
This possibility comes straight from a Cory Doctorow novel. The easy suspicion, though, is a characteristic of America's post-WWII empire-building.