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The military's equipment was also outdated and designed to look out over the ocean to deal with a Cold War threat.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 515.

    re: Shanksville, Pennsylvania
    Bush did give the order for any further suspected hijacked planes to be shot down after the first aircraft were flown into the World Trade Centre in New York during the 2001 terror attacks.

  • rate this

    Comment number 514.


    Some people think that believing in government statements, makes them "smarter" than others ..after all, they know something which 10000s of people who did their own research don't.

  • rate this

    Comment number 513.

    @414. mike90000
    Google "Operation Northwoods"
    Google CIA LSD public experiments
    ...and stand corrected.

  • rate this

    Comment number 512.

    The New Pearl Harbor: Disturbing Questions About the Bush Administration and 9/11 by David Ray Griffen provides significant detail on this subject. The question we should continue to ask ourselves is 'Who was set to benefit the most from the war on terror?' which may therefore lend some credence to these conspiracy theory’s.

  • rate this

    Comment number 511.

    @ 374: The USA changing the universal date format (11/9 vs. 9/11) is just another conspiracy that we're going to take over the planet by subverting the calendar. You just have to read the conspiracy theory Websites that have so much secret information only they can get it.

    And it's frightening to know many of them support intelligent design, too. And vote Wing-Nut. We're doomed, but not by DC....

  • rate this

    Comment number 510.

    Collapse of the Twin Towers

    Your statement "No evidence has ever been found of explosive charges."

    But Professor Steven Jones claims to have found evidence of nano thermite in the dust produced by the collapse. He could be wrong, but to claim their is NO EVIDENCE is a false statement.

    Plus there have been pictures of beams cut at strange angles that have remained unexplained.

  • rate this

    Comment number 509.

    Of course the conspiracy theorists are all nuts.But one thing you haven't mentioned is the fact that your own Jane Standley..the well respected BBC reporter on the scene, actually reported the collapse of WTC7 an hour before it did! When questioned on this she gets hostille and defensive. The BBC can only give these conspiracy nutters more ammo by not explaining or even mentioning it!

  • rate this

    Comment number 508.

    I don't believe in a US government-orchestrated conspiracy but I do believe it is possible that it was known about and allowed to proceed. Unfortunately the US is not short of people nasty and devious enough for that. Even the famous PNAC document mentioned a Pearl [or should that be Pearle!] Harbour type attack that could be used as a pretext for middle east intervention.

  • rate this

    Comment number 507.

    Unbelievable! You CT's really think that the US govt would do this to their own people to "further" their cause????
    Get a life please!

    Anyone can put any slant on whatever they want to, doesn't make it the truth. Things happen in weird and mysterious ways all the time, things happen that can't be explained or they don't happen as one might expect. Terrorists did this. End of.

  • rate this

    Comment number 506.

    To Frank Lund, i think the forensics people could distinguish between thermite and paint or rust somehow

  • rate this

    Comment number 505.


    e = m * c * c

    9/11 + 7/7 = 17/6 = 87.5p

  • rate this

    Comment number 504.

    e=mc2 IS NOT theory how do you think they know the yield of a nuclear weapon or material in a power station?

  • rate this

    Comment number 503.

    Freddie Roach Ate My Hamster

    No, my friend, just because you believe it does not make it facts.

    The 9/11 Commission has been condemned as a whitewash by those employed to oversee it. And i don't believe most of the drivel on here either way. You don't seem to have noticed i state no view either way.

    Your assumption of my beliefs is simply that; an assumption

  • rate this

    Comment number 502.

    387. BBCnews 101
    52 Minutes ago

    Its amazing how many clever people there are on this site who have their eyes closed, and want to stay oblivious to any other point of veiw.

    Look at the physics, it cant lie.

    It can't. But idiots can misrepresent and distort the conclusions drawn from it.

    And MANY more scientists, engineers and other QUALIFIED experts AGREE with the official story than not.

  • rate this

    Comment number 501.

    Can't we all agree, as some have already pointed out, that, fundamentally, these were deplorable acts committed by man on fellow man, causing the deaths of many, many people, in turn leaving gaping holes in the lives of tens of thousands of family & friends. 10 years on, would it not be more pleasant to respect these FACTS, as well as focus on the continued rebuilding of a city as great as NYC??

  • rate this

    Comment number 500.

    Occam's Razor dictates that we do not multiply quantities unnecessarily. Thus the simplest explanation is usually understood to be the correct one. In my experience conspiracy theories are more complicated than the official explanations so defy this principle. Incompetence rather than conspiracy is simpler & more common. To err is human.

  • rate this

    Comment number 499.

    Do you have a gas cooker ? Why hasnt it collapsed in a heap on the floor? According to the official report it should have done .

    Looking at the collapse supposedly a 'pancake' collapse, why is there a very large peice of debris going UPWARDS, later to be found embedded in a building opposite weighing a few times that of a jumbo jet ?

  • rate this

    Comment number 498.


    The Empire State Building was massively over engineered as the technique was new. More modern buildings make much more ecconomical use of materials.

  • rate this

    Comment number 497.

    "No evidence .... despite the extensive hand searches"
    BUT, Gulliani had all the debris removed as quickly as possible and the investigators were NOT allowed totally free access to the site.

  • rate this

    Comment number 496.

    RE: Failure to intercept the hijacked planes.

    So what you are saying is that US fighter jets can only intercept enemy planes that helpfully indicate their locations using transponders. Or that they don't have target radar. Or that F-16's cannot cover 140 nautical miles in less than 40 minutes.

    Are you actually saying that?

    Because most people will see that as a lie. Because it is.


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