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The military's equipment was also outdated and designed to look out over the ocean to deal with a Cold War threat.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 655.

    Maybe I should have posted the link to the NIST page where the report on building 7's collapse is published.


    Strangely enough, the .pdf file stops downloading after about 1.5MB.

    I don't know what to read into that, but for anyone interested in analysing the report then it's a bit frustrating.

  • rate this

    Comment number 654.

    The conspiracy theory was born from the actions of the US Gov.

    Search You Tube for Rumsfeld and Bush seperately saying Flight 93 was shot down.

    Search You Tube for Bush saying he saw the first plane crash into the tower before he went into the classroom (footage of the first crash did not appear till the next day).

    Bush and Cheney refusing to go under oath for the 9/11 commission stinks.

  • rate this

    Comment number 653.


    Fact; now means in my opinion

  • rate this

    Comment number 652.

    641. Some other person with a comment
    "So sad to see how stupid humanity has become. The net was supposed to liberate and educate, instead people use it as a tool to keep bad ideas alive, and destroy their own minds."
    Or people use it to gratuitously insult others and indulge their misplaced sense of superiority, like you do. Which is actually even more sad.

    Signing off. Have fun!!!

  • rate this

    Comment number 651.

    @634 avi8ar
    The fireball(s) outside WTC 1/2 show(s) what happens when combustion occurs with sufficient oxygen. The smoke that poured from the damaged towers indicates insufficient oxygen for complete combustion which lowers the temperature of the fire.
    What of the waving woman from one of the gashes left by one of the planes? Was she waving from a severely temperature softened area of the tower?

  • rate this

    Comment number 650.


    "OK airframes are built on the limit of strength to weight ratios but to say that they're lightweight is just silly"

    Lightweight construction. So wings would disintegrate fairly easily same with fins etc. It's all to do with momentum to be honest, so most of the energy would be concentrated in a small area at the tip of the nose. That would explain the number of walls penetrated.

  • rate this

    Comment number 649.

    the usa and uk government feed lies all the time and people and the media included lap it up

    what happend to the war on terror? they were all from saudi and yeman ..yet the usa does big business with them nations

  • rate this

    Comment number 648.

    many hundreds of thousands of innocent people died as a direct result of this event and all of our future freedom and wellbeing in the balance and some people are happy to just tow the line. namecalling, uneducated and ill informed opinion thrown around like they mean something and only distracting from the real issue. if you value the freedom that others died for please at least inform yourselves

  • rate this

    Comment number 647.

    Everyone in the world knows it was an inside job - everyone apart from a handful of idiots that is.

    To date we haven't seen a single video which really shows that truth. The BBC least of all. They like to pretend to be 'middle of the road,' when we all know that they like to kiss US ass at every opportunity.

  • rate this

    Comment number 646.

    I see Chris Whitlow is another who merely repeats falsehoods: When WTC7 fell there were many recording devices in the area being used by the media & not one recorded any loud explosions.
    NIST closely examined both the dust & the steel - no thermite or evidence of it.
    It is YOU,Chris, who perpetuates the errors omissions, thus belittling the horroe of what happened.

  • rate this

    Comment number 645.


    I would suggest very few people believe their Governments, what they don't do is construct fantasies. Most if all Government inquires are sanitised in there favour.

  • rate this

    Comment number 644.

    How do they explain the seismic records? Check the USGS website.

  • rate this

    Comment number 643.

    Put your hands up if you believe the passport of a terrorist on one of the planes escaped the fireball, jumped out of his pocket, fluttered down to the ground, escaped being buried in debris and dust, to be found and passed to the FBI who from this passport have the names of all 19 hijackers within hours and Bin Laden is to blame.

    Nope..thought not. Yet when the US Gov say it ??

  • rate this

    Comment number 642.

    Chris, do all those 100+ people think explosives were what they heard or just "explosions" in general? You know, like when gas pipes rupture or other things "explode". I think the majority of those people and the majority of people if they heard a large "boom" might say they heard an "explosion". Perhaps you are suggesting somebody saying they heard "explosions" it must mean explosives where used.

  • rate this

    Comment number 641.

    Lots of nutters in here today...

    Going through the old "see this link, it has proof" diatribe.

    Most of these links are ancient (by internet standards) and are full of debunked misinformation.

    So sad to see how stupid humanity has become. The net was supposed to liberate and educate, instead people use it as a tool to keep bad ideas alive, and destroy their own minds.

    Signing off. Have fun!!!

  • rate this

    Comment number 640.

    Sorry for my verbal redundancy .
    I said "dimwit conspiracy theorist"

  • rate this

    Comment number 639.

    630.Chris Whitrow
    4 Minutes ago
    ".....and over 100 witnesses testify to explosions."

    Misrepresentation of basic facts in evidence :
    Most, of not ALL those witnesses said words to the effect of "When steel beams snapped under stress, or floors collapsed, the noises were LIKE explosions"

    NEVER that there WERE explosions.

  • rate this

    Comment number 638.

    @583 Ex Tory Voter

    What a resourceful fellow you aren't ... let me assist.
    Here is Danny Jowenko's company and website.
    He was one of Europes leading demolition experts.


    Sadly he died last month when his car hit a tree.

  • rate this

    Comment number 637.

    To rework the old joke, two conspiracy theorists die and go to Heaven where they are given the opportunity to ask God a question.
    "Who was responsible to 9-11?" says one.
    "It was a terrorist attack, nothing more.", God answers.
    "Hmm." says the conspiracy theorist "This is bigger than we thought!"

  • rate this

    Comment number 636.

    People should read about Operation Northwoods before they label conspiracy theorists as paranoid.

    In the 1960s, the CIA planned to kill American citizens and blame Cuba. By vilifying Cuban, they could justify an invasion.

    Some believe that 9/11 was planned, or at least allowed to happen, by US Intelligence Agents in order to vilify Islam and initiate a "war on terror" in resource rich countries


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