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The controlled demolition hypothesis is the disputed proposition that the World Trade Center was not destroyed by the planes that crashed into it as part of the September 11th attacks, nor by the fires that followed, but by explosives or other devices planted in the buildings in advance. Though the findings of the National Institute of Standards and Technology (NIST) do not suggest that controlled demolition was involved, the hypothesis has become central to the 9/11 Truth Movement. The most detailed statements of the hypothesis have come from Steven E. Jones, Kevin Ryan, Jim Hoffman, David Ray Griffin and Webster Griffin Tarpley. In making their case, they often emphasize the collapse of 7 World Trade Center, which was not hit by a plane.

While it is has won significant popular support, the idea of controlled demolition is normally presented as a hypothesis still to be tested, not a proven claim. Mainstream engineers, official investigators, and industry experts generally dismiss the idea and are not currently carrying out such tests.

Overview

While engineers were initially very surprised by the collapse of the World Trade Center, the broad outlines of a collapse theory quickly emerged in the days that followed the attacks of September 11, 2001. The details have been significantly revised as investigations proceeded, but engineers have consistently attributed the collapse of the main towers to the combination of structural damage from the impact and weakening of the steel frame due to the fires. Although the investigation into the collapse of WTC 7 has not yet been completed, the working hypothesis also suggests a combination of structural damage and weakening by fire.

Proponents of the controlled demolition hypothesis are critical of this consensus. Specifically, they do not accept that fire could weaken the buildings sufficiently to initiate collapse (even given the structural damage). They also do not accept that, after the collapses began, the buildings would collapse completely, straight down, and at near free-fall speed without an additional source of destructive energy. It is argued, therefore, that the additional energy needed to undermine the structure must have come from secondary devices planted in the building before September 11, 2001. This is normally presented as a plausible hypothesis in need of independent testing.

In addition to this basic disagreement with the official explanation, proponents of the controlled demolition hypothesis point to a variety of features of the actual collapses that, they argue, is more consistent with demolition than progressive collapse. These features appear mainly in stages of the collapses that the official investigation did not deem relevant to understanding how they happened.

In its final report, NIST stated that it "found no corroborating evidence for alternative hypotheses suggesting that the WTC towers were brought down by controlled demolition using explosives planted prior to September 11, 2001" and posted an FAQ about related issues to its website in August of 2006. The hypothesis has also never been suggested in mainstream engineering scholarship and its proponents are considered "outsiders". Explicit criticism of the controlled demolition hypothesis normally involves a combination of a defense of the official account of the collapses and an emphasis on the insurmountable difficulties of arranging the demolition of such large buildings covertly. By association with other 9/11 conspiracy theories, the controlled demolition hypothesis is also often accused of being disrespectful of the victims of 9/11 and their families.

World Trade Center Seven

Videos that show the fall of 7 World Trade Center have become a mainstay of presentations of the controlled demolition hypothesis. This was a 47-story steel-framed skyscraper that stood across Vesey Street north of the main WTC complex. Though not hit by a plane, it collapsed at about 5:20 p.m. EDT on the evening of September 11, 2001. No modern, steel-reinforced high-rise, had ever before collapsed because of an uncontrolled fire. NIST has postponed publication of its report several times, attributing the delays to reassignment of investigators to other tasks.

In addition to its being officially unexplained, proponents of controlled demolition often emphasize the collapse of WTC7 for two reasons. First, because it was not hit by a plane and, second, because its collapse looked even more like a bottom-to-top standard controlled demolition than the more explosive top-to-bottom collapses of the two main towers. Support for this theory comes from visually observed features of the collapse--the swift and symmetrical fall, the pulverization of concrete, the lateral ejection of debris from high up for large distances. They also cite an early report of molten and partly evaporated steel found in the debris.

In the PBS documentary America Rebuilds, which aired in September 2002, Larry Silverstein, the owner of Building Seven and leaseholder and insurance policy holder for the remainder of the WTC Complex, recalled a conversation with the Fire Department commander in which it was decided that "the smartest thing to do is just pull it", after which they "watched the building collapse." While Silverstein has issued a statement that rejects this interpretation, proponents of controlled demolition have taken the remark as a confession that the building was intentionally demolished.

In a New York Magazine interview in March 2006, Dr S. Shyam Sunder, NIST's lead WTC disaster investigator, said "We are studying the horizontal movement east to west, internal to the structure, on the fifth to seventh floors," and then added, "but truthfully, I don’t really know. We’ve had trouble getting a handle on Building No. 7." Hugo Bachmann and Jörg Schneider, both of the Swiss Federal Institute of Technology, believe that building 7 was intentionally demolished based on video footage.

Proponents have timed the collapse at just under seven seconds. Preliminary official investigations do not include the mechanics of the actual collapse, concentrating instead on the events leading up to it. The FEMA report begins its "timed collapse sequence" with a seismic event recorded at 5:22:33 pm. FEMA marks this as the time the building "begins to collapse." At this time, the report says, the east and west mechanical penthouses--the structures at the very top of the building--are still intact. Approximately thirty seconds later, FEMA says, video evidence shows the east mechanical penthouse begin to disappear into the building. Five seconds later the west penthouse also disappears, and at 5:22:10 "WTC 7 collapses completely." This is roughly the point at which Jones begins timing the collapse, noting that his results correspond with the free, unimpeded fall of the roofline. This observed "near freefall" collapse time is a recurrent theme of the controlled demolition hypothesis.

History

On the day of the attacks, there were reports suggesting explosions and secondary devices. Several journalists reporting on the events speculated that the World Trade Center collapses were caused by intentionally planted explosives and some experts made similar suggestions in the days following the attacks. As an official explanation that did not involve explosives emerged, however, these speculations ceased, and some were retracted.

In a notable example, the Albuquerque Journal quoted Van Romero, Vice President for Research at New Mexico Institute of Mining and Technology, who said that the collapses looked "too methodical" and that his opinion, based on the videotapes, was that there were some explosive devices inside that caused the towers to collapse. He further said "detonation of bombs within the towers is consistent with a common terrorist strategy." After speaking with structural engineers, however, he revised his opinion and said "certainly the fire is what caused the building to fail". He further said he had been misquoted and had "only said that that's what it looked like."

An early version of the controlled-demolition hypothesis, explictly stated in opposition to the official explanation, was formulated by J. McMichael. His ironic essay "Muslims Suspend the Laws of Physics" recalled Romero's initial remarks and introduced some of the lasting elements of the hypothesis: that the fires could not have sufficiently weakened the steel to initiate the collapses, and that the undamaged structure underneath the impact zones would have resisted a total progressive collapse. These ideas were then developed in greater detail by Jeff King and Jim Hoffman on their websites, with little attention from the mainstream media.

Eric Hufschmid's Painful Questions was the first book-length treatment of the hypothesis, and included questions about Building Seven. In 2004 this book was singled out by proponents and debunkers alike. Popular Mechanics started its investigation into this and other 9/11 conspiracy theories when Painful Questions was advertised in the New York Times and theologian David Ray Griffin listed Hufschmid's questions among the reasons to re-investigate the events of 9/11 in his influential book The New Pearl Harbor.

In late 2005, Steven E. Jones, a physicist at Brigham Young University, made his own pursuit of the hypothesis public. Even before peer review and publication of the article in the 2006 book "9/11 and the American Empire: Intellectuals speak out," his interest in the hypothesis brought a measure of scientific credibility and increased media exposure to the theory. In consequence, however, Jones was placed on paid leave by his university in September 2006 for his "increasingly speculative and accusatory" statements.

The controlled demolition hypothesis and the official explanations of the collapse developed alongside each other. Proponents of the controlled demolition hypothesis, for example, were among the first to question the "pancake collapse" hypothesis, in which floors progressively detached from the columns due to the force of higher floors falling on them. This theory, which constituted the official consensus until the middle of 2005, was ultimately rejected by NIST. In its effort to understand the collapse of Building Seven, moreover, NIST claims to be currently developing "hypothetical blast scenarios" that will be of interest to proponents of controlled demolition. Likewise, Zdenek P. Bazant, who co-authored the first published analysis of the collapses of the two towers, has proposed examining data from controlled demolitions in order to better model the progressive-collapse of the towers. The controlled demolition hypothesis has been pursued mainly by experts in fields other than structural engineering and by a network of amateur investigators.

An August 2006 poll concluded that 16 percent of Americans considered it at least somewhat likely that "the collapse of the twin towers in New York was aided by explosives secretly planted in the two buildings."

Notable proponents

The most notable statements of the controlled demolition hypothesis have been made by Steven Jones, David Ray Griffin, Webster Griffin Tarpley and Kevin Ryan. Jones has published his paper "Why Indeed Did the World Trade Center Buildings Collapse?" in a book called 9/11 and the American Empire: Intellectuals Speak Out, edited by Peter Dale Scott and David Ray Griffin. Griffin, a retired professor of theology, published his own version of the hypothesis in The Hidden History of 9-11-2001, a book of critical essays on 9/11 edited by Paul Zarembka. Webster Griffin Tarpley has devoted a chapter of his book 9/11 Synthetic Terror to the hypothesis. Kevin Ryan, who was fired from his job at Underwriters Laboratories for voicing his criticism of the official investigation, has also contributed chapter to the Griffin and Scott volume.

All these authors refer to the controlled demolition of the World Trade Center as a hypothesis in need of further investigation before it can be accepted as true. Their accounts of the hypothesis overlap in many ways, but they each offer a distinct perspective. Jones concentrates on the physical plausibility of the official explanation and possible similarities to controlled demolition. While Griffin also summarizes suggestive physical features of the collapses, he adds a reading of the oral histories that were released by the New York Fire Department in August 2005 and published by the New York Times. These constitute a substantial body of eyewitness testimony of the collapses and the events that led to them. Tarpley takes a more historical view, emphasizing expert opinions proposing controlled demolition shortly after the attacks; the behavior of government agencies (especially the New York Mayor's Office) in the handling of the WTC site; and public criticism of the official investigation into the collapses. This criticism of both the motives and the methods of official investigations is central to the defense of the controlled demolition hypothesis and here Ryan's contribution has become influential.

Main towers

Like WTC 7, both of the main towers collapsed at essentially the rate of free fall. While fires were still burning, the top sank into the damage area. A cloud developed around the failure as it progressed downward, and large pieces of debris fell away from the sides of the building. As the cloud reached the level of other buildings, it expanded through the streets of surrounding blocks. Along with WTC 7, the Twin Towers are the only buildings of their kind to have suffered global collapse as a result of local damage. This lack of precendent is often emphasized by proponents of the controlled demolition hypothesis.

Because a detailed official explanation of these collapses is available, proponents present controlled demolition as an alternative hypothesis that better explains the data, i.e., the observable aspects of the collapses. They often emphasize the symmetry, completeness and near free-fall speed of the collapses; the reported sounds of explosions; the shooting out of debris and smoke (so-called "squibs"); and reports of molten metal. Counter-arguments by official investigators and mainstream engineers rarely deny these aspects of the collapses, but offer explanations for them that do not depend on preplanted explosives or other devices in the buildings.

Basic argument

Proponents often encourage their audiences to compare the video footage of the collapses of the WTC towers with footage of known controlled demolitions. They count the following features of the WTC collapses among telltale signs of controlled demolition:

• Direction of descent: The towers collapsed around their bases rather than tipping over in one direction. Debris fell to all sides.
• Speed of descent: The towers came down just slightly slower than the rate of free fall in a vacuum.
• Demolition waves: Proponents claim that small, apparently timed explosions occurred around the perimeter of each tower.
• Demolition squibs: As the towers collapsed they exhibited what appeared to be high-velocity gas ejections well below the descending rubble.
• Pulverization: The towers' non-metallic components, such as their concrete floors, were pulverized into fine dust.
• Totality: The towers were destroyed totally, their steel skeletons allegedly shredded into pieces less than 30 feet long.

Steven Jones has argued that without explosives to destroy the internal support structure of the WTC towers, the fall of the towers would violate the principle of conservation of momentum. He says that the collapse of the towers at near free-fall speed indicates that the central core below the impact zone had lost its structural integrity and thus provided almost no resistance to the falling upper stories. Controlled demolition, he says, is the best way to explain this lack of structural resistance.

Photographs and videos show tightly focused horizontal plumes of smoke and debris being ejected from the twin towers during the collapse. The plumes appear approximately 10 stories below the area of main destruction and are ejected only from the centers of the towers. These plumes appear in both towers, at regular intervals, and from multiple camera angles. They are identified by proponents of controlled demolition as evidence for "squibs", i.e., explosing shaped charges intentionally destroying the structure of the buildings.

The official theory says the plumes consisted merely of material ejected due to the evacuation of air as the floors collapsed.

Engineers who have investigated the collapses also deny that their appearance was suspicious or suggests a controlled demolition. Thomas Eagar, professor of materials engineering and engineering systems at MIT, said that the towers could not have fallen by tipping over. He notes that the top would have to be displaced by 100 feet to move the center of gravity outside the base, and that the steel columns would have buckled well in advance of this. Bažant and colleagues have commented that, although the top of the south tower initially tilted significantly, this tilting did not continue because the horizontal reaction to the rate of angular momentum would have have exceeded the shear resistance of the lower story by a factor of at least 10.3.

The total collapses of WTC 1 and 2 have not been modeled with the intention of either refuting or confirming the controlled-demolition hypothesis. The NIST report provided a finite element analysis of the structural response of the building up to the point where, NIST says, collapse was inevitable due to the enormous weight of the buildings above the damaged floors. NIST did not, however, simulate the structural response of the lower floors, which are of primary interest to supporters of the demolition theory. Bažant and Zhou, in the days after the attacks, provided some rough estimates that would support NIST's approach. They concluded that the weight was at least an "order of magnitude" over that required to occasion total collapse. Bažant and Verdure later reaffirmed this in 2006.

NIST has noted, as its primary reasons for rejecting the controlled demolition hypothesis, that the failure began specifically in the damage area and progressed downward. Implosive demolitions initially sever supports at the bottom of the building to start the whole structure moving downward. Explosive charges higher in the building serve only to fragment the debris.

Demolishing buildings by implosion typically requires weeks of active preparation. This preparation includes removing non-supporting walls, cutting non-essential structural elements, and drilling into the steel supports to place explosive charges. Most charges are placed in the bottom floors of the building, although charges may be placed higher to reduce the size of the debris. NIST raised logistical objections to Jones's thermite hypothesis, saying that cutting through the vertical columns would require placing "many thousands of pounds of thermite" inconspicuously before the collapse, igniting it remotely, and holding it in contact with the columns. At least one documentary on the controlled demolition hypothesis has addressed the question of logistics.

Critique of fire theory

Proponents of controlled demolition argue that the fires could not have been hot enough, nor burnt long enough, to significantly weaken the steel in the buildings to a point of collapse. Sometimes they refer also to examples such as NIST's 2004 fire test in which sample structures exposed to fire were shown to be "able to withstand standard fire conditions for between one and two hours" without failure.

Some have compared the heat of the fires in the twin towers and the fires' effect on steel to findings in actual fire tests carried out by steel manufacturer Corus (formerly British Steel) on unprotected steel beams in open-sided car parks. The highest recorded steel temperatures in those parks when beams were exposed to hydrocarbon-fuelled fires was 360°C, well below the estimated 800°C temperature of the steel supports in the twin towers at the time of the fires.

Several studies made by NIST also showed that temperatures were relatively low. A paint study shows that neither perimeter nor core columns were exposed to temperatures exceeding 615°C for longer than 15 minutes and mostly temperatures were below 250°C. Furthermore the simulation data in the NIST report indicates that the temperature of the steel was falling at the time of collapse.

Oral history

There were a number of eyewitness accounts of explosions just prior to the start of the collapse of the towers. These are cited as evidence for controlled demolition. Witness statements are numerous, redundant and detailed. "It seemed like it was going all the way around like a belt, all these explosions," one witness said. "You see three explosions and then the whole thing coming down," said another. Many firefighters, in oral histories obtained by the NY Times, also testified to what they perceived as explosions.

A few witnesses describe what they believed to be 'basement bombs'. William Rodriguez, a WTC janitor in the North Tower at that time, reported that while he was in the basement of the north tower with about 20 others a large explosion took place on Sublevel B3 actually before the plane hit. He reports people running up the stairs with "skin hanging off of their bodies" He said Mike Pecoraro, a mechanical engineer who had seen the bomb attack in 1993 and was working in the sixth sub-basement of the north tower on 9/11, also gave detailed observations of what he believed to be damage from bombs. WTC construction worker Phillip Morelli described a basement explosion sound at the time of the plane impact that knocked him to the ground, although he later explained that it was most likely the freight elevators being cut loose above and hitting the ground. Some researchers suggest other possible reasons for explosions in the basements, such as explosions of electrical equipment.Many other witnesses of explosions hold to their stories; many eyewitness accounts by firefighters recorded at that time were released in late 2006 and describe features of bombs detonating before and during the collapses.

Some firefighters who had reported explosions later came to a different view of what they had perceived. For example, one said, "We realized later after talking and finding out" that the ten or so "explosions" he and others had heard coming from the south tower were actually "the floors collapsing to where the plane had hit."

Thermite hypothesis

Proponents of controlled demolition argue there was evidence of temperatures well beyond those that, by general consensus, can be attributed to the fires. Steven Jones, specifically, believes observed molten material was actually molten iron, a byproduct of a thermite reaction. Thermite reactions can reach temperatures of up to 4500°F (2500°C), well beyond the temperature (approximately 1500°C) required to melt structural steel. He takes this to be an indication that thermite, a metallic agent used in incendiary munitions, might have provided the energy required to demolish the buildings.

NIST proposed that some of the observed molten metal may have been molten aluminum from the fuselage of the plane. Aluminum melts at significantly lower temperatures than steel.

In late 2006 Jones conducted molecular analyses to ascertain the presence of explosive residues on steel samples from Ground Zero and in the released dust and says he found chemicals consistent with the presence of thermate (a mixture of thermite and other oxidizing agents used in incendiary munitions). The initial FEMA investigation team also found sulfur within the structural steel from 7 WTC along with indications of extremely high temperatures. Neither the FEMA study nor the NIST report identify a source for the sulfur, but NIST has since noted that sulfur is present in gypsum drywall and other construction materials used in the towers.

Dust clouds

Some have argued that the production and expansion of the enormous dust clouds that covered Manhattan after the collapses are an indication of an additional source of energy, such as explosives. They say that the energy required for this expansion alone (ignoring the energy needed to slice the steel and pulverize the concrete and other materials) exceeded the gravitational energy available by at least 10 times. NIST attributes these clouds to the ejection of air from compressed parts of the building. They were once taken as an indication of the subsequently abandoned pancake collapse hypothesis.

Debris removal

Webster Tarpley, in particular, has criticized the official response to the crime scene, saying the speedy cleanup resulted in the destruction of most of the evidence, identifying the New York City Mayor's office as a key player in this regard. Under Tarpley's theory, this would constitute evidence tampering under New York state law.

A call to action by Bill Manning, the chief editor of the trade journal Fire Engineering, is often quoted in this connection. Manning called the early ASCE investigation (which would later turn into the FEMA building performance study) a "half-baked farce" and said that "the destruction and removal of evidence must stop immediately". He said that the cleanup of the WTC site differed in many respects from that of other engineering disasters. In defense of the decision to dispose of the steel, Mayor Bloomberg said: "If you want to take a look at the construction methods and the design, that's in this day and age what computers do." David Ray Griffin notes that this is exactly what Manning had worried about when he warned against letting "the investigation into the World Trade Center fire and collapse will amount to paper-and computer-generated hypotheticals."

In response to concerns about the destruction of evidence, W. Gene Corley, head of the Building Performance Assessment Team on the site, stated, that "The team has had full access to the scrap yards and to the site and has been able to obtain numerous samples." NIST has numerous sections of steel from both Towers as well as 7 WTC.

Popularizations

The research of proponents like Hoffman, Griffin, Jones and Tarpley has entered popular culture by a variety of means, many involving new media. A Scripps/Howard poll found that people who are most likely to endorse this hypothesis get most of their information from the Internet.

Several documentaries have also defended the controlled demolition hypothesis, including 9/11 Mysteries, Improbable Collapse, and Dylan Avery's Loose Change. A number of lectures by Hoffman, Jones and Griffin have also been made available online.

The demolition hypothesis first entered mainstream media by way of negative press coverage of "9/11 conspiracy theories" or "9/11 myths". An article in Popular Mechanics, which was later expanded into a book, also presented the hypothesis to a mainstream audience, as did the popular magazine Skeptic. Such coverage generally takes a very critical view of the hypothesis.

New York Magazine published one of the first major articles that offered a partially sympathetic take on the hypothesis. Finally, the hypothesis has also been cited by a number of celebrities, including David Lynch and Charlie Sheen, inviting much interest from the public.

Reactions from engineers

The controlled demolition hypothesis has been unambiguously rejected by official investigators and mainstream structural engineers.

Zdenek P. Bazant, who was among the first to offer an explanation of the collapses, mentioned the controlled demolition hypothesis in passing in a 2006 paper, co-authored with Mathieu Verdure. Affirming the mainstream consensus as presented in the NIST report, Bazant and Verdure note "a few outsiders claiming a conspiracy with planted explosives" as an exception. They trace "strange ideas" about, among other things, controlled demolition, to a "mistaken impression" that safety margins in design would make the collapses impossible. While strictly speaking superfluous, one of the effects of a more detailed modeling of the progressive collapse, they say, could be to "dispel the myth of planted explosives".

Other engineers, such as Thomas Eagar, have also dismissed the controlled demolition hypothesis with reference to the consensus that has formed in the engineering community about the collapses.

Leslie Robertson, who helped design the Twin Towers, debated Steven Jones on a radio program.

References

1. Oliver, Anthony (2001). "Lasting lessons of WTC". New Civil Engineer. Retrieved 2006-07-28.
2. Gross, John L. (2005-09). "NIST NCSTAR 1-6: Structural Fire Response and Probable Collapse Sequence of the World Trade Center Towers". Federal Building and Fire Safety Investigation of the World Trade Center Disaster. National Institute of Standards and Technology. Retrieved 2007-01-13. {{cite web}}: Check date values in: |date= (help); Unknown parameter |coauthors= ignored (|author= suggested) (help)
3. ^ NIST (2006-08). "Answers to Frequently Asked Questions". Federal Building and Fire Safety Investigation of the World Trade Center Disaster. Retrieved 2006-01-12. {{cite web}}: Check date values in: |date= (help)
4. ^ Jones, Steven E. (2006-09). "Why Indeed Did the World Trade Center Buildings Completely Collapse" (PDF). Journal of 9/11 Studies. 3. Retrieved 2006-01-13. {{cite journal}}: Check date values in: |date= (help)
5. ^ Sunder, Shyam (2005). "Consideration of Public Comments" (pdf). NIST Response to the World Trade Center Disaster. National Institute of Standards and Technology. Retrieved 2006-07-28.. See also NCSTAR1, p. 146.
6. ^ Bažant, Zdenĕk P. (to appear 2007-03). "Mechanics of Progressive Collapse: Learning from World Trade Center and Building Demolitions" (PDF). Journal of Engineering Mechanics. ACSE. Retrieved 2007-01-13. {{cite journal}}: Check date values in: |date= (help); Unknown parameter |coauthors= ignored (|author= suggested) (help)
7. 2 U.S. Reports Seek to Counter Conspiracy Theories About 9/11 New York Times 2006-09-02
8. One collection is available at www.wtc7.net.Videos available online
9. Glanz, James (2001). "Diesel suspected in 7 WTC collapse". Across the nation. Chicago Tribune. Retrieved 2006-07-06.
10. "Identifying Misinformation: 9/11 Revealed?". usinfo.state.gov. 16 September 2005. Retrieved 2007-01-06.
11. Griffin, David Ray in The Hidden History (will fix ref).
12. ^ Blanchard, Brent (2006-08). "A Critical Analysis of the Collapse of WTC Towers 1, 2 & 7 from an Explosives and Conventional Demolition Industry Point of View" (PDF). ImplosionWorld.com. Retrieved 2006-01-12. {{cite web}}: Check date values in: |date= (help)
13. ^ Mark Jacobson (2006). "The Ground Zero Grassy Knoll". New York Magazine. Retrieved 2006-11-26. {{cite web}}: Unknown parameter |month= ignored (help)
14. Ganser, Daniele (2006-09-09). "The embittered controversy over September 11". Tages Anzeiger. Retrieved 2006-09-20.
15. FEMA report re WTC7, page 5-23.
16. Webster Tarpley. 9/11 Synthetic Terror, Chapter 6, quotes Danish military explosives expert Bent Lund from Danish press sources. Kevin Ryan, who supports the controlled-demolition hypothesis, has said that Ronald Hamburger, who worked on the official explanation from an early stage, originally suspected explosives. His initial reaction was published as part of the announcement that he would work on the ASCE study. (PDF here)
17. Uyttebrouck, Oliver. "Explosives Planted In Towers, N.M. Tech Expert Says". Albuquerque Journal. Retrieved 2006-07-28.
18. Fleck, John. "Fire, Not Extra Explosives, Doomed Buildings, Expert Says". Albuquerque Journal. Retrieved 2006-07-28.
19. McMichael, J. "Muslims Suspend the Laws of Physics." Public Action News Service, October 21, 2001 (revised November 25, 2001).
20. Hufschmid, Eric. Painful Questions. Endpoint Software. 2002.
21. ^ Dunbar, Brad (2005-03). "Debunking The 9/11 Myths". Popular Mechanics. Retrieved 2007-01-12. {{cite journal}}: Check date values in: |date= (help); Unknown parameter |coauthors= ignored (|author= suggested) (help)
22. Griffin, David Ray. The New Pearl Harbor. ISBN 1-56656-552-9.
23. Walch, Tad. "BYU places '9/11 truth' professor on paid leave", Deseret Morning News, September 8, 2006.
24. Sullivan, Will (2006-09-11). "BYU takes on a 9/11 conspiracy professor". U.S.News & World Report. www.usnews.com.
25. Hargrove, Thomas (2006-08-02). "Anti-government anger spurs 9/11 conspiracy belief". Scripps Howard News Service. Retrieved 2006-01-12. {{cite news}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
26. Griffin, David Ray (2006-09-30). 9/11 and the American Empire: Intellectuals Speak Out. Olive Branch Press. ISBN 1-56656-659-2. {{cite book}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
27. Zarembka, Paul (2006-05-10). The Hidden History of 9-11-2001. JAI Press. ISBN 0762313056)).
28. Tarpley, Webster Griffin (2005-12-01). 9/11 Synthetic Terror. Tree of Life Publications. ISBN 0-930852-31-1.
29. Griffin, David Ray (2006-09-30). 9/11 and the American Empire: Intellectuals Speak Out. Olive Branch Press. ISBN 1-56656-659-2. {{cite book}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
30. http://911research.wtc7.net/wtc/analysis/compare/fires.html
31. The websites of Controlled Demolition, Inc. and ImplosionWorldmore controlled-demolition videos are often suggested. The Landmark Towers demolition has become a common reference.
32. Griffin, D.R. (October, 2005). "The Destruction of the World Trade Center: Why the Official Account Cannot Be True" (pdf). Progressive Democrats–East Bay, http://www.pdeastbay.org. {{cite journal}}: Check date values in: |date= (help); Cite journal requires |journal= (help); External link in |publisher= (help)
33. http://911research.wtc7.net/wtc/analysis/collapses/squibs.html Squibs
34. http://www.pbs.org/wgbh/nova/wtc/collapse.html
35. ^ "Interview with Stacey Loizeaux". NOVA Online/Kaboom!. Retrieved 2006-01-12.
36. 9/11 Mysteries
37. "NIST Tests Provide Fire Resistance Data On World Trade Center Floor Systems". Science Daily. August 27, 2004. Retrieved 2007-01-05. Note: This story has been adapted from a news release issued by National Institute Of Standards And Technology.
38. Hoffman, Jim (2003–2006). "The Column Failure Theory is Inapplicable". 911research.wtc7.net. Retrieved 2007-01-05.{{cite web}}: CS1 maint: date format (link)
39. Barter, Sheila (13 September, 2001). "How the World Trade Center fell". BBC News. Retrieved 2007-01-05. {{cite web}}: Check date values in: |date= (help)
40. "Analysis of Structural Steel - presentation by Frank W. Gale, NIST" (pdf). NIST. 2004.
41. http://911research.wtc7.net/wtc/evidence/oralhistories/explosions.html
42. "The Firefighters’ Testimony to Explosions in the Twin Towers," released by FDNY in August 2005 under order from the New York Court of Appeals. This material was reviewed by Griffin, David Ray in Explosive Testimony: Revelations about the Twin Towers in the 9/11 Oral Histories.
43. "Janitor tells 9/11 panel of brush with WTC thug". New York Daily News. June 2004. Retrieved 2006-12-08.
44. "We Will Not Forget: A Day of Terror". The Chief Engineer. July 2002. Retrieved 2006-10-04.
45. "Honoring The Survivors". NY1 News. 2002. Retrieved 2006-12-08.
46. "Basement Bombs: Theories that Subterranean Bombs Destroyed the Twin Towers". Retrieved 2006-12-08.
47. http://graphics8.nytimes.com/packages/pdf/nyregion/20050812_WTC_GRAPHIC/9110505.PDF
48. Toreki, Rob (2006). "The Thermite Reaction". The General Chemistry Demo Lab. Interactive Learning Paradigms Incorporated. Retrieved 2006-07-04.
49. "Dr. Jones' Talk at ISU Physics Department Updated 9/11/06" (PDF). http://journalof911studies.com. {{cite web}}: External link in |publisher= (help); Text "first Steve E." ignored (help); Text "last Jones" ignored (help)
50. Barnett, Jonathan (2002). "Limited Metallurgical Examination" (pdf). FEMA 403 -- Appendix C.6, Suggestions for Future Research. Federal Emergency Management Agency. Retrieved 2006-07-04. {{cite web}}: Unknown parameter |coauthors= ignored (|author= suggested) (help) - "The severe corrosion and subsequent erosion of Samples 1 and 2 are a very unusual event. No clear explanation for the source of the sulfur has been identified. The rate of corrosion is also unknown. It is possible that this is the result of long-term heating in the ground following the collapse of the buildings. It is also possible that the phenomenon started prior to collapse and accelerated the weakening of the steel structure. A detailed study into the mechanisms of this phenomenon is needed to determine what risk, if any, is presented to existing steel structures exposed to severe and long-burning fires."
51. Hoffman (“The Twin Towers Demolition”) says that the clouds expanded to five times the diameter of the towers in the first ten seconds. The Demolition of the Kingdome can be viewed at the website of Controlled Demolition, Inc. (http://www.controlled-demolition.com/default.asp?reqLocId=7&reqItemId=20030317140323). The demolition of the Reading Grain Facility can be seen at ImplosionWorld.com (http://implosionworld.com/reading.html).
52. King, Jeff, 2003. “The WTC Collapse: What the Videos Show,” Indymedia Webcast News, November 12 (http://ontario.indymedia.org/display.php3?article_id=7342&group=webcast ).
53. Tarpley, Webster G. 9/11 Synthetic Terror: Made in USA. Chapter 6. ISBN 0930852311
54. Section 215.40 New York State Statutes
55. Manning, Bill. ""Burning Questions...Need Answers": FE's Bill Manning Calls for Comprehensive Investigation of WTC Collapse." Editorial in Fire Engineering. January 4, 2002. &ARTICLE_ID=131225
56. Griffin, David Ray. "The Destruction of the World Trade Center: why the official account cannot be true." (This is an updated version of his chapter in The Hidden History of 9-11.
57. http://www.house.gov/science/hearings/full02/mar06/corley.htm
58. Images of the debris sorting
59. http://www.improbablecollapse.com/ - the documentary website.
60. Links to lectures
61. Molé, Phil. "9/11 Conspiracy Theories: The 9/11 Truth Movement Perspective" and "What Demolition Experts Say About 9/11" in Skeptic, v. 12, n. 4. 2006.
62. Gravois, John (June 23, 2006). "Professors of Paranoia? Academics give a scholarly stamp to 9/11 conspiracy theories". The Chronicle of Higher Education. Retrieved 2006-07-27.{{cite web}}: CS1 maint: year (link)
63. Podcast of WTC demolition debate between engineer Leslie Robertson and physicist Steven Jones on KGNU radio, Oct. 26, 2006.

External links

• Podcast of WTC demolition debate between engineer Leslie Robertson and physicist Steven Jones on KGNU radio, Oct. 26, 2006.
• BBC1: September 10, 2006 interview with Dr Griffin about 9/11
• 9/11 The Myth and the Reality: Dr. David Ray Griffin lectures - 44m30s in Dr Griffin speaks about collapses of WTC 1,2 & 7.
• Prof. Steven E. Jones Lifting the Fog Lecture UC Berkeley Campus, November, 11 2006 - Jones speaks about WTC7, molten metal, about thermite and explosive

v t e 9/11 conspiracy theories
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Category

• 1972 architecture
• 1973 architecture
• Alternative theories of September 11, 2001 attacks
• Buildings and structures in Manhattan
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• September 11, 2001 attacks
• Terrorism in the United States
• World Trade Center