In 2010, a survey found that one in four Americans believed that 9/11 had been designed to facilitate the Bush administration’s so-called ‘War on Terror’. The conspiracy theories range from those who believe that US officials either made or let 9/11 happen, to those who argue that a missile hit the Pentagon, that the Twin Towers couldn’t have fallen without demolition explosives, or that United 93 was shot down by the military. Why all the paranoia? Possibly because as Anthony Summers and Robbyn Swan’s The Eleventh Day: The Ultimate Account of 9/11 clearly shows, there has been a cover-up.

“There is a huge amount of people who feel they haven’t been told the truth,” says Summers. “Bright people – not just the loony contingent.”
Explanations for the attack have been dogged with misinformation and downright lies from the very beginning, notes Swan.
“President Bush and Vice-President Cheney repeatedly suggested that al-Qaeda was backed by, or somehow linked to, Iraq and Saddam Hussein. They did this in a drip feed in the months prior to the invasion of Iraq and it convinced a lot of people. That has lingered on long after that has been proven to be untrue.”
These lies and half-truths are responsible for the widespread distrust of the official account.
“There would have been rumours anyway, but the administration really asked for it by saying things which were provably not true,” says Summers. “When you do that, one wonders what you are actually hiding.”
“You have conspiracy theorists starting to raise ideas about the Bush administration having been in some way behind it, such as the two famous theories – ‘Made it happen on purpose’ or, ‘Let it happen on purpose’ – MIHOP and LIHOP. There is no evidence whatsoever to support either of them, but when, in the light of that, they proceed to invade Iraq, that’s just throwing petrol on the fire of the idea of a homemade event.”

There is, however, evidence to suggest that people close to the Saudi power nexus may have facilitated the attacks or at least given support to the terrorists.
“It is quite a complex story and there are two strands to be examined,” notes Swan. “One is the evidence that because of concerns of maintaining their own power, the Royal Family may have paid what amounted to protection money to al-Qaeda to keep them from perpetrating attacks within the Kingdom. Osama bin Laden himself, a member of a very wealthy Saudi family, had been virtually within royal circles as a young man, had been well known within those circles and worked with Saudi intelligence in Afghanistan.”
“In the early ‘90s, bin Laden broke with the Royal Family over the continued presence of American servicemen in Saudi Arabia. There have been questions raised over the extent to which that break was real or simply, in the words of one French intelligence officer we spoke to, ‘A plot for the gullible.’”
“Then there is actual material support and aid and sustenance to the hijackers themselves within the United States. That’s something we have tried to carefully tease out. The bits of evidence that are there were surfaced by the Congressional Joint Inquiry and the 9/11 Commission, that the first two hijackers to arrive in the United States were facilitated on the ground by minor officials within the Saudi embassy and by people with links to the embassy. There are strands of evidence that need to be followed there. The 9/11 Commission staff were allowed to interview those men but only after significant difficulty, in Saudi Arabia, under the eyes of Saudi internal security.”

“I’m not sure those questions could be answered,” says Summers. “Saudi Arabia is such an opaque, enclosed society that one can’t get into it to do a proper investigation. But I think the anger should be directed at the US administration, which in one way or another, put the kibosh on the leads that indicated Saudi involvement by not making anything of it at a national level; and by cosying up, as Bush did on September 13 with Saudi Prince Bander, when it was known that 15 of the 19 hijackers had been Saudi.”
Another significant strand of inquiry is the CIA. How much did they know? Was intelligence botched through human error? Why has nobody within the Agency received any official reprimand?
Tom Wiltshire, deputy chief of the CIA’s bin Laden unit, had information about the arrival of two of the hijackers, Khalid al-Mihdhar and Nawaf al-Hamzi. His official interview is redacted almost entirely.
“There are national security concerns and sometimes those are legitimate,” says Swan.

However, as Summers notes, “The public could see that something had been withheld from them.”
“The CIA knew in advance that they were al-Qaeda terrorists and that they had visas to enter the United States, but yet did nothing about it,” says Summers. “Was it just a great big cock-up, as the CIA has suggested? Or was it because the CIA had something else in mind – to monitor them or try to turn them? We don’t know. But it is suggestive that Wiltshire, who was running that particular show at the time, that his whole interview has been redacted. On the other hand, what he says could reveal sources and methods and that is the reason so often for redacting documents.”
It is possible that Wiltshire’s interview may not add anything to the substantial truth, but without this information it is hard to know if the CIA’s failings point to gross incompetence or something some sinister.
“One of the things that the CIA could have done and should have done was to have their own inspector-general review the behaviour of the CIA prior to 9/11 just like the FBI did,” argues Swan. “The CIA have done a report but all they have released is a seven-page executive summary, which tends to blame what happened on mistakes as opposed to wilful behaviour.”

“That said, having claimed that mistakes were made, the inspector-general suggested that there be an accountability review board held for seven named individuals going right up to the director George Tenet himself. Tenet’s successor declined to hold such a review and described the agents involved as some of the agency’s ‘finest’. Well, if your finest officers are carrying out operations in such a manner that they contribute to the deaths of around 3,000 people by mistake, then one should think that the issue needs to be investigated further. That contributes to the aura of ‘what are they hiding?’ Maybe they are hiding the fact that they did make mistakes but if so, somebody should be held accountable.”
“Nobody has been held accountable,” says Summers. “Nobody has been fired or demoted, as far as one can tell.”

If the CIA agents involved have not been held responsible for personal professional mistakes, it suggests that the Agency itself must be riddled with systemic failures – another reason why the full report may have been withheld from the public.
“The question you are asking is what do I think? Do I think there is a secret or was it incompetence?” says Summers. “We can’t prove anything either way. But if you take all the facts together, the multiple mistakes made by the CIA at every turn, and you marry that together with the extraordinary scene of Clinton’s national security advisor, Sandy Berger, being allowed access after 9/11 to the national archives, a hugely senior man caught stuffing documents into his socks and down his shirt. Something extraordinary drives a man like that to conclusively destroy his reputation and career to steal documents. What’s that all about? On balance, I’d say there is a secret, but we don’t know what it is.”

The Eleventh Day: The Ultimate Account of 9/11 is out now published by Ballantine Books