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The military's equipment was also outdated and designed to look out over the ocean to deal with a Cold War threat.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 755.

    I watched the 15 minute video narrated by Ed Asner which did raise some questions about the collapse of Building 7.

    It said that the NIST enquiry report has been classified as secret according to that video because of a "threat to national security" or some similar phrase. But I found it here.


    Strangely though, I can't download it.

  • rate this

    Comment number 754.

    According to ARTHUR SCHEUERMAN, who was a senior firefighter on 9/11, the BBC misheard some info on the orders to evacuate WTC7 as the firefighters predicted it was going to collapse. How would this mistake fit into a well plannecd conspiracy like CT's say 9/11 was?


    Check the above link and relax and stop smoking too much skunk.

  • Comment number 753.

    This comment was removed because the moderators found it broke the house rules. Explain.

  • rate this

    Comment number 752.

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

    Bet they dont mention God.
    Apparantly according to billions of people, all that happens is gods will, so it was god wot dun it, which means god is a terrorist & basically so are all those who support him/her.

    If you want a real conspiracy-
    Who put the ram in ram a lang a ding dong

  • rate this

    Comment number 751.

    While fairly dubious over 9/11 conspiracies, it's also hard to ignore decades, if not centuries of spin and deceit. Can you blame the theorists?

    The rest happily fall in line with what the media dictates. If recent events have shown us anything, that the government uses the media as its national puppet strings. Most don't even question "The Truth" a famous line used by 'that' paper.

  • rate this

    Comment number 750.

    So the Pentagon was hit by a plane? a jumbo jet flying at 500 mph 2 feet above the ground, yet it did not even scorch the lawn? No fuselage was found, only a circular 16 ft diameter hole - CLEARLY A MISSILE NOT A PLANE !!!!

    Why did the BBC announce that Building 7 had collapased 20 minutes before it actually did?

    How did a passport survive the fire to allegedly be found lying on the sidewalk?

  • rate this

    Comment number 749.

    Conspiracy theorists ignore Occam's Razor and tie themselves in knots trying to come up with reasons for supporting their ideas. Turn it around; Al Quaida had clear motivation for a terrorist attack. Who else had such clear motivation? The CIA in some bizarre attempt to bring back Elvis from Mars? Don't be silly. Cui bono? Osama bin Laden.

  • rate this

    Comment number 748.

    Does Terry Cheesecake have a book to sell?

  • rate this

    Comment number 747.

    OK BBC HYS. The comments coming through regarding 9/11 are now too sick to even respond to. As a UK citizen, who lost a daughter. I can't stand to read anymore what nutters, waking up elsewhere, are writing here online, but would not have the courage to say it to my face. Shame on all you online cowards.

  • rate this

    Comment number 746.

    One thing seems clear the BBC do seem to be on a drive to create division and can apply the label "Conspiracy theorist" to anyone voicing a alternative point that they don't support. Its only a Legitimate conspiracy if the BBC say so..OK! Remember the BBC is entirely trustworthy and not at all a government mouthpiece and if you disagree with them and have your own thoughts you are very naughty!

  • rate this

    Comment number 745.

    I believe there is no smoke without fire (pardon the pun) and maybe there's a massive cover-up going on? First there are "No bodies" then there are "Bodies"...very weird! Lot's of contradictory things being reported and why? What have they got to hide? Why do they want us to think there are dead bodies lying around after all? Do they need these bodies for some specific purpose?

  • rate this

    Comment number 744.


    yes, it is a conspiracy to think. And it scares the hell out of those too cowardly and/or stupid to use the brains that evolution/god gave them.

  • rate this

    Comment number 743.

    696. Jericoa

    "How many WOMD were found again someone remind me?

    I would like to see a good answer to that one from the many deniers on here, I wont get one.."

    Err, none, and it kind of proves the point. If the US can pull off brining the towers down I'm sure knocking a few WMD's together would be a walk in the park.

  • rate this

    Comment number 742.

    Jericoa: "launch chemical weapons in 15 min" ? Typo?
    Do you mean: "Intelligence ...indicates that from forward-deployed storage sites, chemical and biological munitions could be with military units and ready for firing within 45 minutes." No evidence needs to be found: 12 October 2004
    UK Foreign Secretary Jack Straw tells the House of Commons that the head of MI6 has withdrawn the claim.

  • Comment number 741.

    This comment was removed because the moderators found it broke the house rules. Explain.

  • rate this

    Comment number 740.

    The most worrying aspect is that we allow these, 'Conspiracy theorists' @ loonies,. to have the vote and sit on jurys.

  • rate this

    Comment number 739.

    @710 Read Animal Farm

    I think TerryCheesecake is making as valid a point, he is making things up too. at least he isn't resorting to CAPITALS to convince us that a made up fact is actually a FACT, chortle.

  • rate this

    Comment number 738.

    Ken Spare

    read the post just after yours, by bbc_joe

    this is debate, with research and facts. your comment is infantile and reflects only on you.

  • rate this

    Comment number 737.

    @710 What's more insulting to the victims of 9/11. Mocking conspiracy theorists or suggesting that they were killed by their own government?

  • rate this

    Comment number 736.

    The very fact that we live in a world where we know it 'might' have been done by our own people is the problem. Regardless of what the truth is we all know it's not entirely impossible or implausible.


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