The possible link between pre-9/11 Israeli warnings and the watch-listing of the hijackers Mihdhar and Hazmi was pointed out in late 2004 by a retired top corporate lawyer named Gerald Shea, who compiled a 166-page memo  detailing the alleged operations of the Israeli groups in New Jersey, Florida and elsewhere. In the Memo, which is drawn from publicly available source material and which he sent to members of the 9/11 Commission and the joint House and Senate intelligence committees, Shea notes that neither the 9/11 Commission’s final report nor the joint report of the intelligence committees "specifically mentions any such [warnings] from the Israeli government". Instead, both reports, hewing closely to the CIA’s public stance, attribute the watch-listing of Mihdhar and Hazmi solely to the bumbling work of U.S. intelligence. But a review of the alleged facts in this route to the watch list, Shea insists, makes one doubt their veracity. "The issue is important", Shea argues, "because any downplaying of Israeli warnings draws attention away" from the surveillance role the Israeli groups may have played.
The key element in the CIA’s account is the claim that in January 2001 the agency had identified an operational link between the Mihdhar-Hazmi duo and one of Bin Laden’s most trusted lieutenants, Khallad, a.k.a. Tawfiq bin Attash, who was suspected of masterminding the 2000 bombing of the USS Cole. According to the CIA, Mihdhar, Hazmi and Khallad had together attended a high-level al-Qaeda meeting in Kuala Lumpur in January 2000. This meeting was historic in the annals of Islamic terrorism, for it was here that the germ of 9/11 was seeded. The significance of the establishment of the link with Khallad was such that CIA Director George Tenet lauded the discovery in his testimony before the Joint Inquiry of Congress in 2002, noting that "this was the first time that CIA could definitively place al-Hazmi and al-Mihdhar with a known al-Qaeda operative [Khallad]". Khallad, it was claimed, had been identified in January 2001 from photographs taken at Kuala Lumpur. That identification was noted officially in an alleged January 5, 2001, CIA cable.
According to the CIA, in the spring of 2001 there were reported threats of al- Qaeda attacks on U.S. interests abroad. A CIA agent whom the Commission calls "John" - who was later identified as agent Tom Wilshire by New Yorker writer Lawrence Wright - "wondered where the attacks might occur". Wilshire was particularly interested in cable traffic relating to the Kuala Lumpur meeting the previous year, specifically the January 5, 2001, cable that identified Khallad as having been present at that January 2000 meeting. It was Wilshire’s efforts, beginning in May of 2001, that the CIA claims led to the watch-listing of Mihdhar and Hazmi on the eve of the attacks.
Yet a mile-wide hole quickly appears in this account, because the purported "definitive" identification of Khallad in January 2001 had been entirely mistaken. In other words, George Tenet in his statement before the Joint Inquiry was either lying or woefully uninformed. According to the CIA’s account, the identification of Khallad, which occurred a year after the actual Kuala Lumpur meeting, came as the result of an FBI/CIA source, who reportedly was able to pinpoint the photographs of Khallad taken at the meeting.
But, according to the CIA’s own Jan. 5, 2001, cable on the matter, the FBI/CIA source was said to have been shown photographs only of Mihdhar and Hazmi. He was not shown a photograph of Khallad. According to the Joint Inquiry report, it was later discovered, after Sept. 11, 2001, that the supposed photograph in question — the one reviewed by the informant in January 2001 — was not of Khallad but of Hazmi himself. And in fact the source erroneously identified Hazmi as Khallad. Or so the Joint Inquiry report claims. But in fact there is substantial doubt as to whether even a mistaken identification was ever made. Three people were said to have been present when the FBI/CIA source made the identification. These included the questioning CIA agent, an FBI agent observing, and the joint source. But, according to the 9/11 Commission’s own staff statements, the FBI agent later said that he was unaware of any identification of Khallad. And the CIA agent, who supposedly conducted the interview, "does not recall this particular identification [at all]", according to the Commission’s staff statements.
So it turns out no one who was said to have witnessed the pivotal identification of Khallad actually recalls any such identification as having been made at all. This in turn suggests it may never have happened.
Indeed, when in May 2001 CIA agent Tom Wilshire allegedly asked another agent, whom the 9/11 Commission does not identify but whom we can here dub "Alice", to review the cable traffic relating to the Kuala Lumpur meeting, Alice later "could [even] recall this work", according to the Commission’s staff statements. (The reference to Alice’s failed memory was later deleted, without explanation, from the Commission’s final report.) In late July or sometime early in August, the CIA’s account continues, Wilshire, still inspired by the purported identification of Khallad in the January 2001 cable, asked another agent, "Mary", to "resume" the work that Alice could not recall. Mary is said then to have discovered, on August 21, 2001, that Mihdhar, and possibly Hazmi, were in the United States. They were both placed on the watch list on August 24 in a tortuous culmination of CIA work that supposedly began with Tom Wilshire in the spring.
Given the litany of unlikelihoods in the CIA’s account — not least of which is the "uncertain, unwitnessed, unremembered" identification of Khallad, as Gerald Shea notes — the reported Mossad warnings appear to lead a far straighter course to the watch-listing of Mihdhar and Hazmi.