World Trade Center controlled demolition conspiracy theories

Template:911tm The controlled demolition hypothesis is a 9/11 conspiracy theory that claims the World Trade Center was not destroyed by the planes that crashed into it as part of the September 11, 2001 attacks, nor by the fires that followed, but by explosives or other devices planted in the buildings in advance. It was first suggested in late 2001 and has since become increasingly important to the 9/11 Truth Movement, but is rejected by the mainstream media and by the engineering community.

The most detailed statements of the hypothesis have come from physicist Steven Jones, architect Richard Gage, software engineer Jim Hoffman, theologian David Ray Griffin, and author Webster Griffin Tarpley. In addition to citing witness accounts reporting explosions in the buildings prior to collapse, it proponents argue that the aircraft impacts and resulting fires could not have weakened the buildings sufficiently to initiate collapse and that the buildings would in any case not have collapsed as completely, symmetrically, and quickly as they did without an additional source of destructive energy to undermine their structure. Various sources of this energy have been proposed; thermite and explosives is the most common suggestion being made today.

The National Institute of Standards and Technology (NIST), an agency of the United States Department of Commerce, has rejected the hypothesis that collapse due to fire would be impossible, as has the engineering community. Members of the 9/11 Truth movement have requested correction of the NIST report.

History

Controlled demolition hypothesis proponents cite mainstream news reports on the day of the attacks that suggested explosions and secondary devices. Journalists and experts commenting on the events as they happened speculated that the World Trade Center collapses were caused by intentionally planted explosives. ABC News anchor Peter Jennings said "Anybody who ever watched a building being demolished on purpose knows that if you're going to do this you have to get at the under infrastructure of a building and bring it down" While watching footage of the collapse of WTC 7, CBS News anchor Dan Rather said "For the third time today, its reminiscent of those pictures we've all seen too much on television before when a building was deliberately destroyed by well-placed dynamite to knock it down." Some of these suggestions would later be retracted or revised. In a notable example, the Albuquerque Journal quoted Dr. Van D. Romero, an engineer who said that the collapses looked "too methodical" and that "some explosive devices inside ... caused the towers to collapse," speculating that the collision of the planes into the towers was a diversionary attack intended to attract emergency personnel to the scene, followed by the detonation of "a relatively small amount of explosives placed in strategic points" of the towers as the primary attack. He soon withdrew this assessment and later said he had been misquoted: "I only said that that's what it looked like."

Engineers were in fact initially surprised by the collapses and at least one considered explosives as a possible explanation. The broad outlines of an explanation that did not involve such explosives quickly emerged, however, and took its current shape in the 2005 NIST report. It has come to be known as "the official account" among proponents of controlled demolition. The hypothesis has gained support in part because engineers were unable to explain how the falling sections passed through the undamaged building beneath, bringing the towers down quickly and completely.

The hypothesis was first suggested as a part of a conspiracy theory in October 2001. An early book-length treatment of the hypothesis inspired both David Ray Griffin's critical inquiry as well as the Popular Mechanics investigation of 9/11 conspiracy theories. In late 2005, Brigham Young University Professor of Physics Steven Jones made his own pursuit of the hypothesis public. Even before publication of the article in 2006, his interest in the hypothesis brought a measure of scientific credibility and media exposure to the theory. BYU responded to Jones' "increasingly speculative and accusatory" statements by placing him on paid leave in September, 2006. Shortly thereafter, Jones accepted BYU's offer of early retirement.

Proponents of the controlled demolition questioned the "pancake collapse" hypothesis originally suggested by FEMA before the NIST finally replaced it with the current column failure theory.

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 a FAQ about related issues to its website in August of 2006. The major elements of the hypothesis have been rebutted in mainstream engineering scholarship, where its proponents are considered "outsiders."

A 2006 poll found that 6 percent of Americans considered it "very likely" that "the collapse of the twin towers in New York was aided by explosives secretly planted in the two buildings," while another 10% found it "somewhat likely." 77% found the demolition hypothesis "unlikely." A 2007 poll found that 67% of Americans fault the 9/11 Commission for not investigating the collapse of World Trade Center 7.

World Trade Center Seven

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Building damage to the southwest corner and smoke plume along the South face of WTC 7, looking from the World Financial Plaza.

7 World Trade Center was a 47-story steel-framed skyscraper that stood across Vesey Street north of the main WTC complex. Its tenants included the CIA, Department of Defense, IRS, Secret Service and the Securities and Exchange Commission. Though not hit by a plane, it collapsed at about 5:20 p.m. EDT on the evening of September 11, 2001.

Some journalists commenting on the nature of the collapse of WTC 7 said that it resembled a controlled demolition, although the explanation that fires in the building, started by falling debris from the collapse of WTC 1, had caused the structure to fail, quickly emerged. No steel-frame high rise had ever before collapsed because of a fire. BBC News reported the collapse of WTC 7 twenty minutes before it actually fell. The BBC has stated that many news sources were reporting the imminent collapse of WTC 7 on the day of the attacks.

In a New York Magazine interview in March 2006, Dr S. Shyam Sunder, NIST's lead WTC disaster investigator granted that they were having "trouble getting a handle on Building No. 7." NIST has postponed publication of its report several times, attributing the delays to reassignment of investigators to other tasks such as the main towers investigation. The initial FEMA investigation report noted that its "best hypothesis has only a low probability of occurrence" and called for a more thorough investigation.

In addition to its remaining unexplained, proponents of controlled demolition often emphasize the collapse of WTC 7 because its collapse looked like a bottom-to-top conventional controlled demolition, as opposed to the more explosive top-to-bottom collapses of the two main towers. Support for this theory comes from features argued to have been visually observed in the collapse--the speed of the collapse, the way it fell down vertically and symmetrically, the rapid onset, the way the center of the roof fell first, lateral ejections of debris observed, and the way the rubble fell mostly within the building's footprint. The initial FEMA investigation team also found sulfur within the structural steel from WTC 7 which they could not explain: "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.". Steven Jones claims that sulphur is evidence that indicates the use of explosives such as thermate, along with reports of molten metal and extremely high temperatures in the rubble.

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WTC 7 at the moment of collapse: the shape of the roof and debris plumes are cited as evidence for controlled demolition.

In the PBS documentary America Rebuilds, which aired in September 2002, Larry Silverstein, the owner of WTC 7 and leaseholder and insurance policy holder for the remainder of the WTC Complex, recalled a discussion with the fire department in which doubts about containing the fires were expressed. Silverstein recalled saying, "We've had such terrible loss of life, maybe the smartest thing to do is pull it". "They made that decision to pull," he recalled, "and we watched the building collapse." Some proponents of the controlled demolition hypothesis have taken the remark as a confession that he ordered the building to be demolished. Silverstein issued a statement that rejects this interpretation, asserting that it was the firefighting team, not the building, that was to be pulled.

Hugo Bachmann and Jörg Schneider, professors emeritus of structural engineering at the Swiss Federal Institute of Technology, believe that WTC 7 was intentionally demolished based on video footage. The 9/11 Family Steering Committee also asked what happened to WTC 7 in their 'Questions Regarding the 9/11 Commission Interview of Mayor Rudy Giuliani,' asking, "On 9/11, no aircraft hit WTC 7. Why did the building fall at 5:20 PM that evening?"

Preliminary 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 5:20:33 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 5:21:10 "WTC 7 collapses completely." This is roughly the point at which proponents of the controlled demolition hypothesis begin timing the collapse, noting that the observed times correspond with the free, unimpeded fall of the roofline: just under seven seconds.

Main towers

The controlled demolition hypothesis is also offered to explain dramatic collapses of the two main towers of the World Trade Center complex on September 11, 2001. It emphasizes the speed, symmetry and totality of the collapses, which, it suggests, could not have been caused by the airplane crashes alone. The effects of the fires and the progress of the collapses after they began have been the main areas of contention.

The hypothesis suggests that the fires could not have been hot enough to weaken the steel structure of the two towers to the point of collapse. However, those who pursue the hypothesis emphasize evidence of temperatures well beyond those that, by general consensus, can be attributed to the fires. Molten metal streamed out of the south tower shortly before it collapsed. There are first-hand reports of claims that molten metal was discovered in the piles of rubble in the weeks following the collapses. Steven Jones has argued that the molten metal may have been 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.

In response, NIST has pointed out that cutting through the vertical columns would require planting an enormous amount of explosives inconspicuously in highly secured buildings, then igniting it remotely while keeping it in contact with the columns. 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.

The controlled demolition hypothesis is also offered to explain a belief that the towers collapsed close to free fall speed. Most estimates agree that the structures offered little resistance to the progress of the collapses and that they took about 50% longer than a free falling object dropped from the tops of the towers. Without explosives to destroy the internal support structure of the WTC towers, argue proponents of controlled demolition, the fall of the towers would violate the principle of conservation of momentum. . Others say that these claims are only supported by intuition without any quantitative analysis. They point to their own analyses posted on a website suggesting that the fall may be explained without violating the principle of conservation of momentum and without requiring any explosives.

The official account does not describe any damage to the structure beneath the impact zone and attempts to confirm or refute the controlled demolition hypothesis by modeling the collapses of WTC 1 and 2 have not borne fruit. An early effort indicated that once collapse began, the kinetic energy imparted by a falling upper section onto the floor below was at least ten times greater than that which the lower section could support. The NIST report provides an analysis of the structural response of the building only up to the point where collapse begins, and asserts that the enormous kinetic energy transferred by the falling part of the building makes "progressive collapse" inevitable once an initial collapse occurs. Supporters of the controlled demolition hypothesis often emphasize that NIST did not simulate the structural response of the lower parts of the buildings, which they find of primary interest, but do not analyze either.

Engineers who have investigated the collapses generally deny that controlled demolition is required to understand the structural response of the buildings. While the top of one of the towers did tilt significantly, it could not ultimately have fallen into the street, they argue, because any such tilting would place sufficient strain on the lower story (acting as a pivot) that it would collapse long before the top had sufficiently shifted its center of gravity. Indeed, they argue, there is very little difference between progressive collapse with or without explosives in terms of the resistance that the structures could provide after collapse began.

First, proponents often encourage their audiences to compare the video footage of the collapses of the WTC towers with footage of known controlled demolitions. Among the most commonly cited similarities are tightly focused horizontal plumes of smoke and debris being ejected from the twin towers just before and during the collapse. While these plumes are normally attributed to material ejected due to the compression of air as the floors collapsed, they are sometimes taken as evidence for exploding demolition charges ("squibs") by proponents of controlled demolition. Second, they cite a large number of eyewitness accounts made by firefighters and emergency medical responders of explosions just prior to the start of the collapse of the towers as evidence for controlled demolition. Finally, the production and expansion of the enormous dust clouds that covered Manhattan after the collapses have also been taken as an indication of an additional source of energy, such as explosives. Some conspiracy theorists suggest 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 9.7e12 J to 4.2e13 J. This corresponds to extra energy of about 2000 to 10000 tons of TNT, or 40 to 200 times the yield of the most powerful conventional bomb. NIST attributes these clouds to the ejection of air from compressed parts of the building.

Debris removal

Most of the structural steel in the World Trade Center was removed from the site and recycled before it could be examined by engineers. Proponents of controlled demolition often see this as part of a cover up. Webster Griffin Tarpley, an author, 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.

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 that "the investigation into the World Trade Center fire and collapse will amount to paper-and computer-generated hypotheticals."

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 a chapter to the Griffin and Scott volume. While his work remains largely self-published, Jim Hoffman's detailed web site, 9-11 Research, is often cited by proponents of the controlled demolition hypothesis as an inspiration.

Criticism of the NIST Report

Criticism of the NIST Report plays a prominent role in presentations of the hypothesis. Critics point out that the report does not provide an account of the structural behaviour of the towers after the collapses began. This is important because "much of the external evidence for controlled demolition typically comes after collapse initiation". It is argued that not modelling the totality of the collapses allowed NIST to ignore evidence of demolition, such as the complete, rapid and symmetrical nature of the collapses, the observed explosive "squibs", the early drop of the North Tower antenna, and the pools of molten metal found in the rubble. Kevin Ryan's criticism of the NIST investigation and subsequent report is often mentioned in this regard. Jones also criticises NIST for "tweaking" the computer simulations of the pre-collapse sequence "until [it got] the desired result.”

On February 28, 2007, NIST's conclusion 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" was challenged in a request for correction (per Section 515 of Public Law 106-554). The request was based on NIST's acknowledgement that it did not investigate controlled demolition nor look for evidence.

The investigation of 7 World Trade Center is ongoing; it has been delayed for a number of reasons, including that NIST staff who had been working on 7 World Trade Center were assigned full-time from June 2004 to September 2005, to work on the investigation of the collapse of the twin towers. NIST anticipates the release of a draft report of 7 World Trade Center in 2008. The NIST is utilizing ANSYS to model events leading up to collapse initiation and LS-DYNA models to simulate the global response to initiating events.

Reaction of the engineering community

The controlled demolition hypothesis has been dismissed in the structural engineering literature. Northwestern University Professor of Civil Engineering Zdeněk Bažant, who was among the first to offer a published peer reviewed hypothesis of the collapses, mentions the controlled demolition hypothesis in passing in a 2007 paper, co-authored with Mathieu Verdure. Affirming the view as presented in the NIST report, they note "a few outsiders claiming a conspiracy with planted explosives" as an exception. Bažant and Verdure trace such "strange ideas" 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". Indeed, Bažant and Verdure have proposed examining data from controlled demolitions in order to better model the progressive-collapse of the towers, suggesting that progressive collapse and controlled demolition are not two separate modes of failure (as the controlled demolition hypothesis assumes).

Thomas Eagar, a professor of materials science and engineering at the Massachusetts Institute of Technology, also dismissed the controlled demolition hypothesis. Eagar remarked, "These people (in the 9/11 truth movement) use the 'reverse scientific method.' They determine what happened, throw out all the data that doesn't fit their conclusion, and then hail their findings as the only possible conclusion." Finally, Leslie Robertson, who helped design the Twin Towers, debated Steven Jones on a radio program in December 2006.

In April of 2008, advocates of the demolition hypothesis proposed a discussion in the engineering community in a peer-reviewed article published in a civil engineering journal. They have also created organizations toward associating professionals in architecture and engineering.

In popular culture

The demolition hypothesis first entered mainstream media by way of negative press coverage of "9/11 conspiracy theories" or "9/11 myths." Critical articles in Popular Mechanics, which were later expanded into a book, and the popular magazine Skeptic presented rebuttals to the hypothesis for a mainstream audience. In 2006, a New York Magazine reported that, "A new generation of conspiracy theorists is at work on a secret history of New York’s most terrible day." In 2006, the hypothesis was cited by Charlie Sheen. The controlled demolition hypothesis is also featured prominently in the controversial online documentary Zeitgeist, the Movie.