9/11 conspiracy theories


It may be 10 years since the attacks in the US on 11 September, but conspiracy theories have not faded over time, says Mike Rudin.

Numerous official reports have been published since the Twin Towers fell, but just when a piece of evidence casts doubt on one theory, the focus then shifts to the next "unanswered question".

Here are five of the most prominent 9/11 conspiracy theories circulating in online communities.

1. Failure to intercept the hijacked planes

The question: Why did the world's most powerful air force fail to intercept any of the four hijacked planes?

Conspiracy theorists say: The then US Vice President Dick Cheney ordered the military to stand down and not to intercept the planes.

File photo of a F-15 fighter Fighter jets failed to intercept the hijacked planes

Official reports say: This was a highly unusual multiple hijacking with violence on board, and where the transponder, which identifies the plane, was turned off or changed.

What is more, a routine military training exercise happened to be taking place that day at US air defence command.

Air traffic controller Colin Scoggins was in constant contact with the military and did not see any lack of response. There was confusion and a lack of communication between the civilian air traffic control (FAA) and the military.

The military's equipment was also outdated and designed to look out over the ocean to deal with a Cold War threat.

2. Collapse of the Twin Towers

The question: Why did the Twin Towers collapse so quickly, within their own footprint, after fires on a few floors that lasted only for an hour or two?

Conspiracy theorists say: The Twin Towers were destroyed by controlled demolitions. Theories relate to the rapid collapse (about 10 seconds), the relatively short-lived fires (56 minutes in World Trade Center 2 or 102 minutes in World Trade Center 1), reports of the sounds of explosions shortly before the collapse, and the violent ejections that could be seen at some windows many floors below the collapse.

Remains of World Trade Center buildings after the attacks on 11 September 2001 Five new skyscrapers are being built on the World Trade Center site

Official reports say: An extensive inquiry by the National Institute of Standards and Technology concluded that the planes severed and damaged support columns and dislodged fire-proofing.

Around 10,000 gallons of jet fuel were spewed over many floors starting widespread fires. Temperatures of up to 1,000C caused the floors to sag and the perimeter columns to bend, causing the sounds of "explosions".

The massive weight of the floors dropped, creating a dynamic load far in excess of what the columns were designed for. Debris was forced out of the windows as the floors above collapsed.

Controlled demolition is nearly always carried out from the bottom floors up, yet this collapse started at the top.

No evidence has ever been found of explosive charges despite the extensive hand searches and there is no evidence of any pre-cutting of columns or walls, which is routinely carried out in a controlled demolition.

3. Attack on the Pentagon

The question: How could an amateur pilot fly a commercial plane in a complicated manoeuvre and crash it into the headquarters of the world's most powerful military, 78 minutes after the first report of a possible hijack and leave no trace?

Part of the outer wall of the Pentagon collapsed after Flight 77 crashed into it A memorial in the grounds of the Pentagon marks the deaths of those who died when Flight 77 crashed

Conspiracy theorists say: A commercial Boeing 757 did not hit the building but instead a missile, a small aircraft or an unmanned drone was used. But since evidence has increasingly shown that the American Airlines Flight 77 did hit the building, the emphasis has shifted to questioning the difficult approach manoeuvre. It is argued it was not under the control of al-Qaeda but the Pentagon itself.

Official reports say: Airplane wreckage, including the black boxes, were recovered from the scene and they were catalogued by the FBI.

Although some early video did not show much wreckage, there is a good deal of video and still photography which shows plane wreckage and evidence of the flight path, such as broken lamp posts.

The remains of crew and passengers on the plane were found and positively identified by DNA. Witnesses also saw the plane strike the Pentagon.

4. The fourth plane - United Airlines flight 93

The question: Why was the crash site at Shanksville, Pennsylvania, so small and why was the aircraft debris not visible?

Conspiracy theorists argue: United Airlines flight 93 was shot down by a missile and disintegrated in mid air, scattering the wreckage over a large area.

The crash site of Flight 93 at Shanksville, Pennsylvania Forty-four people died when Flight 93 crashed in Shanksville, Pennsylvania

Official reports say: There are clear photographs showing aircraft wreckage and the cockpit voice recorder, which showed there had been a passenger revolt and the hijackers had deliberately crashed the plane.

Initial theories that heavy debris was scattered many miles from the main crash site turned out to be false. In fact the wind had blown light debris such as paper and insulation just over a mile.

Another theory was based on a misquote from the local coroner, Wally Miller, who said he stopped being a coroner after about 20 minutes because there were no bodies. What he also said was that he quickly realised it was a plane crash and there would have to be a large funeral service for the many victims.

In addition, the military never gave orders to the air force to shoot the commercial airliner down.

5. Collapse of World Trade Center Building 7

The question: How could a skyscraper, which was not hit by a plane, collapse so quickly and symmetrically, when no other steel-framed skyscraper has collapsed because of fire?

The remains of World Trade Center Building 7 Offices for civil emergencies, the CIA and the Secret Service were based in World Trade Center Building 7

Conspiracy theorists say: The World Trade Center Building 7 was destroyed by a controlled demolition using both explosives and incendiaries.

Initially the focus was on the phrase "pull it" used by the owner, Larry Silverstein, in a TV interview. But in fact he was talking about pulling firefighters back. (Demolition experts do not use the term "pull it" as slang for setting off explosives.)

Now the focus has shifted to the speed of the collapse which reached near free fall for 2.25 seconds. It is argued only explosives could make it collapse so quickly and symmetrically.

Some scientists, who are sceptical of the official account, have examined four dust samples from Ground Zero and claim to have found thermitic material which reacts violently when heated up. They claim tonnes of thermite and conventional explosives were rigged inside, not just WTC7, but also the Twin Towers.

Find out more

  • The Conspiracy Files: 9/11 - Ten Years On will be broadcast on Monday 29 August 2011 at 21:00 BST on BBC Two

Official reports say: A three-year investigation by the National Institute of Standards and Technology concluded that the building collapsed because of uncontrolled fires, started by the collapse of the nearby North Tower, and which burnt for seven hours.

The mains water feeding the emergency sprinkler system was severed. No evidence has ever been found of explosive charges and there are no recordings of a series of very loud explosions that would have been expected with controlled demolition.

Furthermore, there is an alternative explanation for the "thermitic material" the sceptical scientists found in the dust - it is just a type of primer paint. It's calculated 1,200,000 tonnes of building materials were pulverised at the World Trade Center and most minerals are present in the dust (not necessarily in a large quantity). More extensive sampling of the dust has not found any evidence of thermite or explosives, says a report from the US Geological Survey and another from RJ Lee.


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  • rate this

    Comment number 735.

    The overused term "conspiracy theory": the official story is that Bin Laden organised things secretly in Afghanistan - does that itself not constitute a "conspiracy"? Rather than let this phrase continue to induce well conditioned negative reactions, how about just dropping it? If one needs a term for theories that deviate from the official story, how about "alternative explanations" or suchlike?

  • rate this

    Comment number 734.

    LoneWolf3, Dimitri will answer your questions also.

  • rate this

    Comment number 733.

    Anybody not agree that aircraft black boxes are made from the toughest materials we have?
    Anybody not agree that a passport is made from paper?

    Now subject a passport and a black box to a 500 mph impact and a 1000 degree fireball and tell me if you think the passport will come off best, because that's exactly what you have been told happened and you not only believe it but you actually defend it.

  • rate this

    Comment number 732.

    TerryCheescake..keep em coming :)

    I dont beleive the US Gov version where you do but I respect humour when I see it.

    As a visitor to New York and eating their enormous portions I can confirm gravity is greater in NY which is why the towers fell at free fall speed.

  • rate this

    Comment number 731.

    As I see it the conspiracy theory states that missile firing, unmanned drones were flown into the trade centres which had already been packed with explosives, without anybody noticing, ready for demolition. Somehow the explosives were kept from going off in the following fires until the order was given for the buildings to be collapsed.

    Occams razor does not apply.

  • rate this

    Comment number 730.

    Terrycheesecake actualy makes a better point than most on here.

  • rate this

    Comment number 729.

    There was no conspiracy that day, but there were a number of terrorist attacks. The real tragedy, was that it couldn't be prevented from happening in the first place.

  • rate this

    Comment number 728.

    How sad that this article dismisses, in a single paragraph, what 1500 architects and engineers have challenged, - that the towers could NOT have collapsed into their own footsteps because of the impact of a plane...supported by the collapse of Tower SEVEN in the same manner, although it was NOT hit at all by any plane. Look up 9/11 FACTS, and A&E for 9/11 Truth.

  • rate this

    Comment number 727.


    So, apart from the US Gov having more to lose than gain by complicity what other motive do you suggest?
    Are you going to tell me that killing its own population can be offset against the price of oil?!!!

    I have yet to hear ONE reason why the US Gov would do this - I wai with baited breath.

  • rate this

    Comment number 726.

    Shift That Paradigm
    10 Minutes ago

    @677 Frank Lund

    Try: http://911research.wtc7.net/wtc/evidence/moltensteel.html

    There are many others.

    There are many more of these debunking wild, unprovable, incorrect assertions from the "tuthers! -_-

  • rate this

    Comment number 725.

    @710. Read Animal Farm regarding TerryCheesecake.

    Wow! He's having a pop at the conspiracy theorists not at the events of 9/11. Is satire not a word in the world you live in? Really? Really? Oh sorry I forgot CTs don't like people that don't share the same wacked out opinion.

  • rate this

    Comment number 724.

    661.david morgan
    36 Minutes ago
    aske ten witnesses of an event for a version of the event and you can get ten different answers
    Almost right David. You would probably get twelve different answers

  • rate this

    Comment number 723.

    Which country has benefited the most from 9/11?

  • rate this

    Comment number 722.

    The incident is history now, who knows what revisionists will have determined as "the truth" in a hundred years time. The new ones look stubby, they just dont have the effect the towers had.

  • rate this

    Comment number 721.

    from looking at the comments its clear who the paid cointel-pro trolls are, terrycheesecake and sbdags are 2 of them, they are very easy to spot! research 9/11 ppl, it was a blatant inside job! so many reasons why it defies belief!!

  • rate this

    Comment number 720.

    As a keen student of geometric shapes I would like to confirm that an aeroplane wouldn't stand a chance of puncturing a polgon as mighty as the pentagon.

  • rate this

    Comment number 719.

    FYI, the report by RJ Lee, to which you link, actually supports the controlled demolition hypothesis, as it confirms the finding of iron microspheres in the dust. NIST admits that temperatures sufficient to melt iron were never present in the towers, so where do the microspheres of elemental iron (not iron oxide) come from? A thermite reaction is the only plausible answer.

  • rate this

    Comment number 718.

    To summarise point #3, it has been shown that AAL077 did hit the Pentagon, so conspiracy theorists now question the difficult approach manoeuvre, saying the 757 was under the control of the Pentagon itself.

    Note that the article does not attempt to refute this idea.

    Is it possible that the 757 was used to deliberately kill those inside the building who planned 9/11, and destroy the evidence?

  • rate this

    Comment number 717.

    What is the BBCs response to the fact they announced the collapse of a building 15 minutes before it happened? I know the BBC like to be on the ball and get the news out first, but 15 minutes ahead of time?

  • rate this

    Comment number 716.

    The CIA and other bits of U.S government have known to of been very shady, if you do some research into the CIA of JFK's time the are reports that they had a plan to lauch a terrorist attack on Miami Florida, for an excuse to attack Cuba. Look into it. They also tryed to assassinate Castro loads of times, unsanctioned.

    Im not saying the CIA is like this anymore but they have had a shady past.


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