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The military's equipment was also outdated and designed to look out over the ocean to deal with a Cold War threat.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 415.


    Red Oxide paint contains iron oxide (so does rust). Aluminium paint contains finely divided aluminium. Simple Thermite = Iron Oxide + Aluminium Powder. Its easy to put evidence of presence of those two materials together and "discover" thermite.

  • rate this

    Comment number 414.

    Wake up....conspiracy nonesense. If the US wanted to take down their own towers, why on earth would they do something so complex. They would have known about all the investigations and theories to follow. Everyone knows that the more complex the lie, the more difficult to cover your tracks..they would never do this to their own people, nor be able to cover it up. Sicko Taliban did it using planes.

  • rate this

    Comment number 413.

    the year 2000, 67 intercepts by US military fighters of hijacked or potentially hijacked planes, 4 planes go missing from radar on 9/11, no intercepts. News reporters on the ground, Diane Sawyer most notebly reported explosions on the ground at WTC. Photos of core columns at ground zero that have been servered consistant with controlled demolition.

  • rate this

    Comment number 412.

    The president of the country these conspiracy theorists come from was forced to show his birth certificate on national TV to prove he was really American, because of the rumour mongering of a few nut-jobs.

    Says it all really.

  • rate this

    Comment number 411.

    337. stuart
    33 Minutes ago

    1000 degrees is not enough to melt steel. Steel melts at 1500. World Trade center building 7, fire caused a building to collapse into itself. You would only believe that if you have 2 braincells. Thermite in paint? good way to destroy buildings, paint them with Thermite.

    And loses its structural strength at around 700degrees C.... next asinine claim, please!

  • rate this

    Comment number 410.

    >This is rubbish. Trying to rate negatively and score goes up 1.

    That's because someone else has rated it up twice at the same time you've rated it down once. Web pages aren't a real-time view of the current state of a page, each time you refresh you will see the latest score.

    Calm down, there's no conspiracy.

  • rate this

    Comment number 409.

    All those sceptics who question how so many people keep quiet about their part in this conspiracy! Simple really - there were a 1000 involved but a 100 upper management each killed 9 operatives, but 90 in turn were killed by top 10 management - who were then killed by the President.
    Must go, nurse here to give me my medicine

  • rate this

    Comment number 408.

    Some people think that believing in conspiracy theories, makes them "smarter" than others ..after all, they know something which scientists don't know, they are better than 10000s of collaborators who would be required to keep the attack under wraps..

    Well, good luck for them.

  • rate this

    Comment number 407.

    Oh and a quick message to the moderators, please stop deleting relevant and important posts from people. If there is nothing to hide then stop the censoring.

  • rate this

    Comment number 406.

    I am not necessarily in support of conspiracy theories generally or any specific examples however I feel it is important for individuals to question events and official accounts if they feel something is not right. And to those suggestion governments are rarely good at keeping secrets, how would you know? All you know are the secrets that were not kept and then base your statement upon this.

  • rate this

    Comment number 405.

    William Rodreguez, was in basement level at 08:46 he reported a massive explosion beneath him, then reported a massive explosion (the plane hitting) just after. Rodreguez testified to the 9/11 commission, it was not part of there report................the dvd 9/11, on scene by the Naudet brothers following a probationary firefigher, have several testimonies of firefighters describing explosions

  • rate this

    Comment number 404.

    Dr. Alan Sabrosky, former Director of Studies at the U.S. Army War College, on audio.

    Why The Military Knows Israel Did 9/11


  • rate this

    Comment number 403.

    If ever you need evidence that the BBC is state television - here it is. A very badly biased piece that supports the status quo - the bbc is a shadow of its former self

  • rate this

    Comment number 402.

    "1000 degrees is not enough to melt steel." Steel doesn't have to melt to collapse. At 1000C it's softened so much it's already lost most of it's strength. This is basic pre-GCSE science but beyond the capacity of the CTs. WTC 7 was badly damaged by debris from WTC 1 or 2, it took out one corner of the building which is always a weak point.

  • rate this

    Comment number 401.

    318.This Is England

    You are correct, but then, one is a single heavy shock loading whilst the other is harmonic occultation and therefore carries different loading stresses to structural integrity. There is also the momentum, stress fracturing, age fatigue of both structure and component elements to consider.
    And I assume many other factors beyond my immediate thought.

  • rate this

    Comment number 400.

    THEORY e+mc2

    FACT... 2+2=4


  • rate this

    Comment number 399.

    All anyone needs to do is ask themselves how many 'coincidences' they would accept before they realise that any given official explanation is a lie! 3? 5? 10? with 9/11 there are at least 50. Ps the co-intel-pro trolls are all over these posts as expected! research 9/11 people! this is important!!!

  • rate this

    Comment number 398.

    Seems 9/11, Princess Diana, JFK and other incidents bring out as many unsubstantiated James Bond theroist. The mere logistcal effort in suppressing the information involved makes these theorise implausible.
    A person or Intelligence unit manpulating a single event in a incident to their own ends is more plausible. But the risk if found out would be tremendous and the consquenses far reaching.

  • rate this

    Comment number 397.


    " the official version of the three towers collapsing"

    There is no official version. The two engineer's reports on the collapses of towers 1 and 2 provide mutually incompatible theories.
    The FEMA study even misrepresents the core structure as a hollow box section and not the steel reinforced concrete load bearing structure it actually was.

  • rate this

    Comment number 396.

    There is historical precedent for conspiracies being true. Some are wide of the mark; doesn't invalidate all. The US House Select Committee on Assassinations concluded that Kennedy was "very likely assassinated as a result of a conspiracy". The 1970s saw Watergate, while in the 1980s we had Iran-Contra.

    Conspiracies happen all the time.


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