World Trade Center controlled demolition conspiracy theories

See also: 9/11 Conspiracy Theories

The Controlled-Demolition Theory states that the World Trade Center buildings which were destroyed during the September 11th attacks were brought down not by the planes which crashed into them but rather by controlled demolitions. This conspiracy theory is rejected by the mainstream mechanical engineering community, the NIST, and the 9/11 Comission. World Trade Center 7 is often separated from the other two collapsed buildings in such discussions; the official report concerning the collapse of WTC 7 is still to be published.

Controlled-demolition theory

The NIST report did not analyze the actual collapse pattern of World Trade Center 1 and World Trade Center 2, the twin towers; the scope of the investigations was limited to the events leading up to the collapse: "The focus of the Investigation was on the sequence of events from the instant of aircraft impact to the initiation of collapse for each tower. [This report] includes little analysis of the structural behavior of the tower after the conditions for collapse initiation were reached and collapse became inevitable." The FEMA report, some say, also did not analyze the actual pattern of the collapse. (For further information on these reports, see 'Government Inquiry')

Skeptics of the progressive collapse, or "pancake" theory, claim there is ample evidence that the towers collapsed due to the systematic destruction of internal supports. Jim Hoffman, a conspiracy theorist and software engineer, says that the telltale signs of controlled demolition, present in the WTC collapse, are:

• Radial symmetry: The Towers came straight down, blowing debris symmetrically in all directions.
• Rapid descent: The Towers came down just slightly slower than the rate of free fall in a vacuum.
• Demolition waves: The Towers were consumed by synchronized rows of confluent explosions.
• Demolition squibs: The Towers exhibited 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 shredded into short pieces, most less than 30 feet long.
• Molten metal: A stream of liquid metal was videotaped flowing out of the corner of 2 WTC moments before collapse, and eyewitnesses observed and reported pools of molten metal in all three rubble piles.

Steven E. Jones, a physics professor at Brigham Young University, and Judy Wood, a mechanical engineer at Clemson University, state that without the use of explosives to destroy the buildings' internal support structure, the fall of the towers violates the principle of conservation of momentum. In addition, Dr. Jones says the angular momentum of the top of the South Tower as it began to collapse could not simply disappear, unless the center of mass of the top was somehow shattered and destroyed. In addition, he claims the collapse of the towers at near free-fall speed indicates the central core below the impact zone had lost its structural integrity and provided almost no resistance to the falling debris. The theory is advocated by Jones's group, Scholars for 9/11 Truth.

The NIST responds that they do not support the Pancake Theory either. Rather, they state

"WTC towers collapsed because:

"(1) the impact of the planes severed and damaged support columns, dislodged fireproofing insulation coating the steel floor trusses and steel columns, and widely dispersed jet fuel over multiple floors; and

"(2) the subsequent unusually large jet-fuel ignited multi-floor fires (which reached temperatures as high as 1,000 degrees Celsius) significantly weakened the floors and columns with dislodged fireproofing to the point where floors sagged and pulled inward on the perimeter columns. This led to the inward bowing of the perimeter columns and failure of the south face of WTC 1 and the east face of WTC 2, initiating the collapse of each of the towers. Both photographic and video evidence—as well as accounts from the New York Police Department aviation unit during a half-hour period prior to collapse—support this sequence for each tower."

The NIST also concludes that the momentum of the upper level structures was so large that the lower level structures would offer little resistance and therefore the building would fall at nearly the free fall rate. The building's structure was only designed to support the static load, not the dynamic forces of collapse.

Molten metal

In the weeks and months after the collapse, there were reports of workers pulling steel beams from the burning rubbles of the WTC, dripping with molten metal. According to reports by FEMA and NIST, molten metal (visible on video) dripped out of the South Tower just before it collapsed. Having analyzed the color of the molten metal, Steven E. Jones believes the metal was at least 1000°C. Others claim the molten metal may simply be aluminum from the aircraft, which melts at about 650°C. Jones has rejected that theory; according to Jones molten aluminum is a poor emitter of black body radiation and should appear silvery-gray under daylight conditions. (The metal in the video is bright yellow.) Jones claims the presence of molten metal at 1000°C would contradict the mainstream collapse hypothesis, according to which that fires in the buildings reached temperatures high enough to weaken the steel, but not to melt it.

In addition to the molten metal, the initial FEMA investigation team found sulfur on parts on the structural steel in the towers and 7 WTC. FEMA was unable to find the source of sulfur, and the NIST report does not mention it. Conspiracy theorists including Steven Jones believe this sulfide may have been caused by the use of a thermite reaction to melt and destroy the steel within the structure. Others have suggested the sulfur originated from gypsum wallboard.

Thermite reactions can reach temperatures of up to 4500°F (2500°C), well beyond the temperature (approximately 1500°C) required to melt structural steel, and with the addition of sulfur can cause an eutectic reaction within such steel. Such a eutectic reaction was observed at WTC and according to professors Ronald R. Biederman and Richard D. Sisson Jr. was "capable of turning a solid steel girder into Swiss cheese." Thermite could explain the presence of the aforementioned molten metal seen dripping out of the South Tower. Steven E. Jones believes this metal is actually molten iron, a byproduct of the thermite reaction.

The NIST concluded that the source of the molten material was aluminum alloys from the aircraft, since these are known to melt between 475 degrees Celsius and 640 degrees Celsius (depending on the particular alloy), well below the expected temperatures (about 1,000 degrees Celsius) in the vicinity of the fires. Aluminum is not expected to ignite at normal fire temperatures and there is no visual indication that the material flowing from the tower was burning. Pure liquid aluminum would be expected to appear silvery. However, the molten metal was very likely mixed with large amounts of hot, partially burned, solid organic materials (e.g., furniture, carpets, partitions and computers) which can display an orange glow, much like logs burning in a fireplace. According to NIST, the apparent color could have been affected by slag formation on the surface.

In response to NIST, Steven E. Jones says he conducted experiments to test NIST's "orange glow" hypothesis. He says that by using several different approaches to mixing organics into molten aluminum, he found that organic material refused to mix and, instead, floated to the top. He says when the mixture was poured, the molten aluminum remained silvery, not orange (with the exception of rougue embers). He claims the outcome of these experiments directly contradict what he describes as NIST's theory that the molten metal seen pouring from the World Trade Center consisted of aluminum alloys.

Symmetry and Squibs

Buildings 1, 2, and 7 of the World Trade Center fell straight down with remarkable symmetry according to 9/11 conspiracy theorists. Without explosives, they say, this symmetry would violate the second law of thermodynamics. They also point to photographs and videos of what they believe are demolition "squibs", which are tightly focused horizontal plumes of smoke and debris being ejected from the twin towers during the collapse. The official theory is that the squibs were merely the ejection of material due to the evacuation of air as the floors collapsed; the plumes, however, 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. Conspiracy theorists say the presence of these squibs indicate secondary explosive devices, activated just ahead of the collapsing material, removing the structural support and allowing total collapse. Some 9/11 conspiracy theorists also believe that squibs were seen in the destruction of 7 WTC, running rapidly up the Southwest corner of the building. They argue that while a possible theory is that the 7 WTC squibs simply result from the floors collapsing, the time between the events is much too rapid to be due to gravitational acceleration.

Molecular and Chemical Support for Demolition

Recently, Professor Steven Jones conducted molecular analyses to ascertain the presence of explosive residues on steel samples from Ground Zero and in the released dust and indicates that chemicals consistent with thermate are present. Other environmental studies have been done on the particulate matter and dust released by the collapse (including a study by the DELTA group at UC Davis), and none have indicated the presence of explosive residue.

Ejected debris

Girders of weight up to 4 tons each were ejected sidewards and found 600 feet from the WTC2. A calculation of ejection speed needed for girders to land so far away is used as an argument for explosives blowing up inside.

Oral History Support for Demolition

As evidence of controlled demolition, some 9/11 conspiracy theorists point to eyewitness descriptions of the events before the collapse of the towers which appeared consistent with explosives, such as "It seemed like it was going all the way around like a belt, all these explosions," and "You see three explosions and then the whole thing coming down," etc.

In addition, William Rodriguez, a high profile survivor was located in the basement of the North tower, when he reported a large explosion on Sublevel B3, before the plane impacted. Rodriguez escaped the building, and escorted several people to safety.

Rodriguez testified before the 9/11 commission, but no official explanation was ever given for the explosions.

Lack of Collapse Precedents

Furthermore, since no steel high-rise building has suffered a total collapse as the result of fire before or since the 9-11 attack, theorists allege the collapse of 1, 2, and 7 WTC are anomalies. The WTC towers burned for less than 102 min (1 WTC) and 56 minutes (2 WTC), during which both towers were stable after the impacts. Theorists consider the following hi-rise fires to be the most similar for comparative purposes:

• 1 New York Plaza (1970) - burned for more than 6 hours, no collapse.
• First Interstate Bank (1988) - burned for 3 1/2 hours, gutted 4 floors of the 64 floor tower, no collapse.
• One Meridian Plaza (1991) - burned for 18 hours, gutted 8 floors of the 38 floor building, no collapse; later had to be demolished.
• Torre Este de Parque Central (Venezuela) (2004) - burned for more than 17 hours, spread to over 26 floors, no collapse.
• The Madrid Windsor Tower (2005) - a partial collapse of some steel sections building while the concrete framework prevented a complete collapse.

Some 9/11 conspiracy theorists say these fires are particularly relevant to WTC7, which was not struck by planes and which suffered damage only from fires and falling debris from the collapse of 1 and 2 WTC.

The Caracas Tower, First Interstate Bank and 1 New York Plaza were constructed using the conventional steel girder system consisting of a grid of steel columns and trusses connecting the columns. The Windsor Tower, however, was constructed with concrete columns and a concrete core for the first 16 floors, steel girder and concrete core for the floors above that, and two additional concrete slabs to provide additional strength.

Steel temperatures

Conspiracy theorists have compared the heat of the fires in the twin towers and the fires' effect on steel to actual fire tests in open sided car parks carried out by steel manufacturer Corus (formerly British Steel) on unprotected steel beams. The highest recorded steel temperatures in open sided car parks when exposed to the hydrocarbon-fuelled fires was 360°C, well below the estimated 800°C temperature of the steel supports in the twin towers (which were not open sided car parks) at the time of the fires.

Several studies made by NIST also showed that temperatures were relatively low. Paint study show 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.

Independent experiments and fire models (or "standard fires") used to evaluate the integrity of structural components demonstrate that hydrocarbon fuels are capable of producing temperatures of 1100°C, and even more when a mix of flammable materials such as office furniture is present. However, these tests do not necessarily duplicate the conditions of real fires, or the behaviour of materials exposed to real fires, and are used primarily as a means of rating materials by using a standardised testing procedure.

The debris

File:Wtcdebris.jpg

A section of fuselage rests in the ruins of the World Trade Center.

In addition to the observation of the collapse, theorists draw upon the remnants of the collapse of the World Trade Center. Opponents of the official story cite the following in support of the controlled demolition theory.

The rubble of the Twin Towers smoldered for weeks after the collapse.

• This claim is meant to point out that steel could only have smoldered as a result of pre-placed explosives. Several observers in and around the debris field utilized phrases containing the words “molten metal” or “molten steel” to describe the devastation. Physicist Steven E. Jones has pointed out that these molten metal observations cannot be known to be steel without a metallurgical analysis being done. The following are some of the more common statements seen:
• The observation of molten metal at Ground Zero was emphasized publicly by Leslie Robertson, the structural engineer responsible for the design of the World Trade Center Towers in a second hand account by James Williams who reported that "As of 21 days after the attack, the fires were still burning and molten steel was still running."

File:Lobby damage and cloud.jpg

The lobby of one of the towers was partially destroyed (broken windows and marble panels) and a dust cloud can be seen rising from the ground during the moments prior to or at the start of collapse.^{(definitive timing needed)}

• Sarah Atlas of New Jersey's Task Force One Urban Search and Rescue, one of the first on the scene said "Fires burned and molten steel flowed in the pile of ruins" (Penn Arts and Sciences, Summer 2002). Similarly, Dr. Allison Geyh, a public health investigator from Johns Hopkins, stated in the Fall 2001 issue of Magazine of Johns Hopkins Public Health, "In some pockets now being uncovered they are finding molten steel."
• Obtaining a conclusive answer to these molten metal reports is difficult because of the lack of debris remaining. While NASA's satellite images of Ground Zero do show large hot spots well after 9/11, they do not provide an exact measure of temperatures within the rubble pile since this type of remote sensing captures only the temperatures on the surface of a debris pile. Independent scientific investigation into what sort of metal, if any, was liquefied has yet to be conducted.

Most of the columns came down in sections about 30 ft (10 m) long and large sections of steel destined for recycling were quickly sent to areas in SE Asia.

• This claim suggests the building was destroyed to provide for an easy clean-up and removal of debris, often implying little study was done of the evidence.
• The longest beam surrounding the towers was no greater than 38 feet.
• It took more than eight months to remove all of the debris from Ground Zero.
• Furthermore, Dr W. Gene Corley, head of the Building Performance Assessment Team on the site, responded to this notion and the evaluation of evidence, "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.

The government has yet to produce the Cockpit voice recorder (CVR) or Flight recorder (FDR) from the WTC attack.

• The Chicago Tribune reported that experts believed the recorders would not be found simply because of the massive scope of the damage and debris. NTSB and FBI have both publicly stated the recorders were never recovered. The 9/11 Commission and federal authorities say that none of the cockpit voice recorder (CVR) and the flight data recorder (FDR) from the two planes that crashed into the Twin Towers were ever found.
• Two men who worked extensively in the wreckage of the World Trade Center claim they helped federal agents find three of the four "black boxes" from the jetliners; this is cited to support the claim there was a government cover-up at Ground Zero (Philadelphia Inquirer, Oct. 28, 2004, [2], Counterpunch.com, Dec. 19, 2005 [3]).

Criticism

Those attempting to debunk 9/11 conspiracy theories have compared the WTC collapses to the Ronan Point disaster, in which one corner of Ronan Point collapsed after a gas explosion. Although Ronan Point was found to be structurally unsound (unsafe), the building did not totally collapse. 9/11 Conspiracy theorist Jim Hoffman has said that the section of the Ronan Point building that collapsed were nonstructural - the short cantilever sections were supported by the building's main structure, making any comparison with the WTC towers unsound. Hoffman states, "The problem with the progressive collapse theory is that it's very difficult to actually build something that will exhibit this behavior."

Structural and civil engineering research

The mainstream of the academic world has yet to be convinced. Massachusetts Institute of Technology has devoted a number of staff members to the analysis of the World Trade Center collapse. The jet crashes and fires have been documented and reviewed within the scientific community. The country's leading structural and civil engineers have examined the attack from the point of impact up through the collapse, concluding that explosives were not necessary to initiate collapse.

The following are a few examples of the structural engineering research done on the collapse:

• According to Farid Alfawak-hiri of the American Institute of Steel Construction, "Steel loses about 50 percent of its strength at 1100 °F (593 °C)." Asif Usmani of Edinburgh University concluded that the interconnecting beams of the towers could have expanded by around 9 cm at 930 °F (500 °C), causing the floors above to buckle.
• Dr. Thomas Eagar, professor of materials engineering and engineering systems at the Massachusetts Institute of Technology, has stated that the building "would have had to have tipped at least 100 feet to one side in order to move its center of gravity from the center of the building out beyond its base." In other words, the structure had no "choice" but to fall straight down.
• Jet fuel wasn't the only thing burning, says Forman Williams, Professor of Engineering at the University of California, San Diego. He says that while the jet fuel was the catalyst for the WTC fires, the resulting fire was intensified by the combustible material inside the buildings, including rugs, curtains, furniture and paper. NIST reports that pockets of fire hit 1832°F (1000°C), high enough to cause structural failure.
• Engineers from the firm Worthington, Skilling, Helle and Jackson said in 1993 the World Trade Center was designed to withstand the impact of a Boeing 707 crash, because they knew a smaller plane had crashed into the Empire State Building. But even then, they warned that it wouldn't be safe from a subsequent fire. "Our analysis indicated that the biggest problem would be the fact that all the fuel [from the jet] would dump into the building," lead structural engineer John Skilling told The Seattle Times in 1993. "There would be a horrendous fire. A lot of people would be killed."

• Although some say that there is a large difference between the Boeing 707, which was popular when the WTC was built, and the Boeing 767s that hit the WTC, others describe the details which show this point to be irrelevant. While the 707 weighs around 330,000 pounds including fuel, the Boeing 767 is about 20 % heavier; however the fuel capacity is about the same for both aircraft. Still, the significant differences in cruise speeds suggests that a 707 in would actually have more kinetic energy than a 767, despite the slightly smaller size. The 767s used on September 11th were estimated to be carrying about 10,000 gallons of fuel each at the time of impact, only about 40% of the capacity of a 707.
• Leslie Robertson, lead structural engineer for the World Trade Center, commented on this point in Reflections on the World Trade Center. Robertson says, “It was assumed that the jetliner would be lost in the fog, seeking to land at JFK or at Newark. Little was known about the effects of a fire from such an aircraft, and no designs were prepared for that circumstance.”
• Robertson illustrates how the kinetic energy of the 767 impact witnessed on 9-11 was nearly seven times greater than the building's design ever anticipated.

World Trade Center: Building 7

File:WTC7.jpg

Building damage to the southwest corner and smoke plume along the South face of 7 WTC, 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 WTC complex. It was not hit by any plane and collapsed at approximately 5:20 p.m. EDT on the evening of Sept 11, 2001. According to experts, no building like WTC7, a modern, steel-reinforced high-rise, had ever collapsed because of an uncontrolled fire , primarily because large fires in such structures are rare, and incidents where those fires are allowed to burn uncontrolled for many hours are so few that no statistical inferences can be drawn about the general ability of these structures to withstand extended fires.

The official report of the 9/11 Commission does not address the collapse of WTC7. NIST has several times postponed the issue date of its report on the collapse of WTC7. Some 9/11 conspiracy theorists say these examples show that an explanation of the collapse of WTC7 is quite difficult, unless the theory of controlled demolition is introduced to explain it.

9/11 conspiracy theorists have proposed the idea that WTC7 collapsed as the result of a controlled demolition. Support for the demolition theory came from the visual observations of the collapse, the pulverization of concrete, the lateral ejection of debris from high up for large distances, and the reports of molten & partly evaporated steel found in the debris. Advocates for this theory point to the speed and the near symmetrical fall of the structure. One source describes the building as coming down in just under seven seconds , although the FEMA report concludes a collapse timeline of 37 seconds.

No conspiracy theorist has given any plausible explanation how the extensive work needed to prepare the building and place charges for demolition might have been performed without attracting the attention of the large number of people who worked in the building, nor how such demolition charges may have been protected from premature detonation caused by the large fires raging in the building on 9/11. Some theories instead suppose that the charges were placed after buildings 1 and 2 had already collapsed, either to destroy evidence or prevent the exposure of sensitive material to the public.

Early tests conducted on steel beams from the World Trade Center show they generally met or were stronger than design requirements, ruling them out as a contributing cause of the collapse of the towers, federal investigators from NIST have stated Building Seven was not struck by an aircraft nor were the fires inside caused or sustained by jet fuel. The official working hypothesis is that Building 7 collapsed as the result of structural damage from the collapsing Towers in addition to prolonged fires throughout sustained by fuel stored for emergency generators. Further discussion of the intensity and severity of the fires is mentioned below. Engineers refer to this type of destruction as a "progressive collapse".

A kink or crimp near the center of the building is identical in appearance to many that have occurred when implosion professionals have made buildings collapse inwards to minimize damage of the surrounding structures.

This observation appears to support the demolition idea which suggests that a carefully calculated fall took place.

Damage, fire, and collapse

According to the controlled demolition theory, among the primary questions unanswered by the official theory regarding Building Seven are the severity of both the damage and the fire. The controlled demolition theorists maintain neither were severe enough to initiate a collapse. Dr. Steven E. Jones, a proponent of the controlled demolition theory, stated regarding Building Seven:

"The likelihood of complete and nearly-symmetrical collapse due to random fires as in the “official” theory is small, since non-symmetrical failure is so much more likely. If one or a few columns had failed, one might expect a portion of the building to crumble while leaving much of the building standing. For example, major portions of WTC 5 remained standing on 9/11 despite very significant impact damage and severe fires."

Dr. Jones also points to concluding notes in the FEMA report on the 7 WTC collapse:

"The specifics of the fires in WTC 7 and how they caused the building to collapse [“official theory”] remain unknown at this time. Although the total diesel fuel on the premises contained massive potential energy, the best hypothesis [fire/debris-damage-caused collapse] has only a low probability of occurrence. Further research, investigation, and analyses are needed to resolve this issue."

Opponents to the controlled demolition theory recognize testimony provided by firefighters and EMT personnel about the severity of the damage to WTC 7. Firefighters used transits to determine whether there was any movement in the structure and were surprised to discover that it was, in fact, moving. A collapse zone was set up at that time, and WTC 7 collapsed about an hour and a half later at 5:20 p.m..

• New York Fire Department personnel on the scene described the damage inflicted to the south face of WTC 7. Several statements were given by firefighters and other first responders emphasizing the critical condition of Building Seven.

The FEMA report provides a timeline of the collapse and photographs of the major events leading up to it. Mechanical penthouses are shown to have collapsed in succession during a 30-second window before the building itself collapsed. The east mechanical penthouse is shown to collapse first. Photographs also show a visible "kink" in the east side of the roofline as the building fell.

The release of NIST's final report on its investigation into the structural failures of Seven World Trade Center has been twice postponed and is scheduled for release sometime in early 2007 . In a New York Magazine interview in March 2006, Dr S. Shyam Sunder, NIST's lead WTC disaster investigator, said that NIST has "had trouble getting a handle on Building No. 7". In draft copies of the report, NIST states that it has "seen no evidence that the collapse of WTC 7 was caused by bombs, missiles, or controlled demolition".

Silverstein's statement to PBS

File:Wtc7-before2.jpg

View from north of 7 WTC ~5:20:33 p.m. It begins to collapse(with both mechanical penthouses standing).

File:Wtc7-after.jpg

~5:21:09 p.m. A north-south "kink" or fault line develops along the eastern side as the building begins to come down at what appears to be the location of the collapse initiation.

Within the PBS documentary America Rebuilds, 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 the collapse of 7 WTC:

I remember getting a call from the Fire Department commander, telling me they were not sure they were gonna be able to contain the fire, and I said, 'You know, we've had such terrible loss of life, maybe the smartest thing to do is just pull it.'... Uh... And they made that decision to pull... and then we watched the building collapse.

Debating the meaning of "Pull It"

To Pull Out Firefighters

Although the term "pull it" may be used in the demolition industry it is also a phrase commonly used in American English to refer to withdrawal of a resource in a wide variety of situations.

One of the firefighters, Richard Banaciski, details explicitly how he witnessed the damage to building 7 from the Verizon building next door (and uses the phrase "they pulled us out"). In a World Trade Center Task Force Interview, Captain Ray Goldbach mentions taking all of their units out of 7 World Trade Center:

I'm going to guess it was after 3:00...We walked all the way back down to Vesey Street. There was a big discussion going on at that point about pulling all of our units out of 7 World Trade Center. ...So at that point we made a decision to take all of our units out of 7 World Trade Center because there was a potential for collapse.

The official FEMA report states that "manual firefighting activities were stopped fairly early in the day" in WTC 7 due to lack of water.

To Pull the Building Down

Since one of the meanings of the word "pull" is industry jargon for planned demolition, some have drawn the conclusion that Silverstein's remark exposes his assent to demolishing the building. The term "pull" used to describe the destruction of a building can be found here, here, and here. Controlled Demolitions, Inc. president Mark Loizeaux used the word "pull" when discussing the destruction of the Kingdome in Seattle. He was specifically discussing how gravity from the roof provided the energy needed to pull the columns inward. His company was also selected to supervise the clean up of the WTC after the attacks. Workers discussing demolition of the six-story WTC6 were using this phrase as well.

Controlled demolition experts at ImplosionWorld.com state that they have never heard the term used to describe demolition of a building with use of explosives. The report states that instead, the term "pull" is used in demolition to describe the act of weakening and physically pulling down the frame of a building with cables, an assertion supported by a recent State Department publication.

Spokesperson explains "pull"

Silverstein's spokesperson, Mr. Dara McQuillan, explained in Sept. 2005 what Mr. Silverstein said:

In the afternoon of September 11, Mr. Silverstein spoke to the Fire Department Commander on site at Seven World Trade Center. The Commander told Mr. Silverstein that there were several firefighters in the building working to contain the fires. Mr. Silverstein expressed his view that the most important thing was to protect the safety of those firefighters, including, if necessary, to have them withdraw from the building.

According to Mr. McQuillan, when Mr. Silverstein said "pull it" he meant the contingent of firefighters remaining in the building.

Disagreements on Silverstein statement

Conspiracy theorist Jim Hoffman concludes: "The Silverstein comment has the appearance of bait, eliciting the widespread circulation of an interpretation that is easily denied if not refuted. While failing to provide substantial evidence for the controlled demolition of WTC 7, the story has functioned to eclipse the overwhelming case for demolition based on the physical characteristics of the collapse..."

Implications of controlled demolition of 7 WTC

If Mr. Silverstein's comments are somehow proven to mean that he okayed the demolition of 7 WTC then that would also imply that the building was already wired with explosive charges before the fire started. In fact, in order to properly bring down a 47 story building requires typically months of preparation and planning (e.g. where to place the demolition charges at key structural points so that the building collapses neatly into its own footprint). It is not standard operating procedure to wire a building with explosives just in case it needs to be demolished in an emergency. If 7 WTC was wired for demolition, it would have to be in preparation for some unusual catastrophic event.