One theory is that individuals within the United States government and private sector knew of the impending attacks and purposefully did not act on that knowledge. Former British Environment Minister Michael Meacher suggested this possibility. The theory does not necessarily suggest that individuals within the US Government actually conducted the operation, but rather that they had enough information to have prevented the attack.
Shortly after the attacks, David Schippers, the chief prosecutor for the impeachment of Bill Clinton, stated that the government had been warned in 1995 about a future attack on a government building and that later he was contacted by three FBI agents who mentioned uncovering a possible terrorist attack planned for lower Manhattan. Interview with David Schippers. Alex Jones Infowars.com. Retrieved on .
- According to the story, as the agents informed their superiors they were briefed not to pursue the issue and threatened with prosecution. David Schippers declared, "Five weeks before the September 11 tragedy, I did my best to get a hold of Attorney General John Ashcroft with my concerns." According to Mr. Schippers, Ashcroft responded that they do not start investigations at the top.
- Mr. Schippers has said the information dated back to a 1995 warning that indicated a possible terrorist attack planned for lower Manhattan using a nuclear device.
- Author William Norman Grigg furthered the Schippers story in his article "Did We Know What Was Coming?" According to the article, three unnamed veteran federal law enforcement agents confirmed "the information provided to Schippers was widely known within the Bureau before September 11."
Rep. Curt Weldon (R-PA) has asserted that over a year before the 9/11 attacks, a classified US intelligence unit known as "Able Danger" identified Mohammed Atta and three other future 9/11 hijackers as likely members of an Al Qaeda cell operating in the US. (Able Danger was a SOCOM exercise.)
- The team recommended that the information be shared with the FBI, but the military's Special Operations Command rejected the recommendation. (New York Times, Four in 9/11 Plot Are Called Tied to Qaeda in '00, 8/9/2005)
- Pentagon officials said they have found three more individuals who recall an intelligence chart identifying Mohamed Atta as a terrorist one year prior to the attacks. 
- FBI agent and Al-Qaeda expert John P. O'Neill warned of an Al-Qaeda threat to the United States in the year preceding the attacks. He retired from his position in mid 2001 after an undisclosed source leaked information to the New York Times about an investigation into an incident that had occurred 13 months earlier. He was then recruited to be chief of security at the World Trade Center. His body was found in a staircase inside the south tower rubble. 
Possible early warning
- On September 12, 2001, The San Francisco Chronicle reported that mayor Willie Brown may have gotten an early warning of the attack, because Brown had said a phone call from his airport security eight hours before the attacks advised him that Americans should be cautious about their air travel. He did not cancel his flight plans until he became aware of the attacks.
- Of the call, Brown said it "didn't come in any alarming fashion, which is why I'm hesitant to make an alarming statement. It was not an abnormal call. I'm always concerned if my flight is going to be on time, and they always alert me when I ought to be careful."
Allegations of insider trading by people with foreknowledge
- In a statement to the 9/11 Commission in 2003, Mindy Kleinberg, of the 9/11 Family Steering Committee, said:
- "Never before on the Chicago Exchange were such large amounts of United and American Airlines options traded. These investors netted a profit of at least $5 million after the September 11th attacks. Interestingly, the names of the investors remain undisclosed and the $5 million remains unclaimed in the Chicago Exchange account." 
However, according to the 9/11 Commission, the SEC and FBI examined each trade, the trades were innocuous, and no evidence of a connection was found:
A single U.S.-based institutional investor with no conceivable ties to al Qaeda purchased 95 percent of the UAL puts on September 6 as part of a trading strategy that also included buying 115,000 shares of American on September 10. Similarly, much of the seemingly suspicious trading in American on September 10 was traced to a specific U.S.-based options trading newsletter, faxed to its subscribers on Sunday, September 9, which recommended these trades (page 51 of the Commission Report, PDF).
- Numerous researchers questioning the official account of 9/11 express doubts that the Commission was actually able to explain worldwide trading patterns around the 9/11 attacks ,
World Trade Center towers
- See also: Collapse of the World Trade Center
Some alternative theories of the collapse of the Twin Towers propose that planted explosives brought down the structures. Much of the support for this claim comes from interpretations of videos and photographs. Several eyewitnesses also reported seeing, hearing and feeling multiple explosions, and explosions in sequence. Many researchers questioning the official account of 9/11 have highlighted the following as evidence for the theory that planted explosives brought down the WTC towers:
The NIST report did not analyze the actual pattern of the WTC's collapse; 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' below)
Skeptics of the progressive collapse, or "pancake" theory, say that there is ample evidence that the towers collapsed due to the systematic destruction of internal supports. Jim Hoffman, a researcher 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, say that without the use of explosives to destroy the buildings' internal support structure, the fall of the towers violates 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 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 provided almost no resistance to the falling debris. The theory is also advocated by Jones's group, Scholars for 9/11 Truth.
In addition to the characteristics of the collapse, eyewitnesses reported pools of molten metal in the rubble of 1, 2, and 7 WTC for several weeks after the collapse. 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, which is an indicator of its temperature, Dr. Jones believes the metal was at least 1000°C. Adherents of the official theory say the molten metal may simply be aluminum from the aircraft, which melts at about 650°C. Dr. Jones rejects this theory since molten aluminum is a poor emitter of black body radiation and thus molten aluminum appears silvery-gray under daylight conditions. (The metal in the video is bright yellow.) According to Jones, the presence of molten metal at 1000°C would contradict the official story, which says 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 did find unusual sulfide 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. Researchers 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 would also explain the presence of the aforementioned molten metal seen dripping out of the South Tower. Dr. Jones believes this metal is actually molten iron, a byproduct of the thermite reaction.
Symmetry and Squibs
1, 2, and 7 WTC also fell straight down with, according to theorists, remarkable symmetry. Without explosives, they say, this symmetry would violate the second law of thermodynamics. Collapse theorists 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. Researchers 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 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. 
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.
His testimony was told to the 9/11 commission, but no explanation was ever given for the explosions.
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. .
Software engineer Jim Hoffman suggests that gravity alone exerts too little energy to explain the pulverization of non-metallic building contents into fine powder, or to explain the pyroclastic flow-like cloud of dust which billowed down the streets of lower Manhattan in all directions.
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 .
Many 9/11 researchers 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 , .
Researchers 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 .
Attempts to Debunk Conspiracy Theories
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. Jim Hoffman has noted 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."  Outside of the Twin Towers and Building 7 collapses, Ronan Point is the most common cited example of a progressive collapse, despite only one corner collapsing and not involving any of the support columns .
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."
- 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. (Images of the debris sorting.)
- 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 claim that none of the cockpit voice recorder (CVR) and the flight data recorder (FDR) from the two planes that crashed into the Twin Towers was ever found, however 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, raising the question of whether there was a government cover-up at Ground Zero (Philadelphia Inquirer, Oct. 28, 2004, http://web.archive.org/web/20041030023935/http:/www.philly.com/mld/dailynews/news/local/10033802.htm; http://counterpunch.org/lindorff12202005.html.
Individuals questioning aspects of the collapse
The following individuals have expressed skepticism or doubt regarding the official theory:
- In a research report, Why Indeed Did the WTC Buildings Collapse?, Brigham Young University Professor of Physics Steven E. Jones writes, "The 'explosive demolition' hypothesis better satisfies tests of repeatability and parsimony and therefore is not 'junk science.' It ought to be seriously, scientifically investigated and debated." ("Why Indeed Did the WTC Buildings Collapse?" by Professor of Physics Steven E. Jones)
- In a letter to Frank Gayle of the National Institute of Standards and Technology, Kevin Ryan of Underwriters Laboratories (UL), wrote "This story just does not add up. If steel from those buildings did soften or melt, I'm sure we can all agree that this was certainly not due to jet fuel fires of any kind, let alone the briefly burning fires in those towers.  That fact should be of a great concern to all Americans. Alternatively, the contention of the steel failing at temperatures around 250 °C suggests that the majority of deaths on 9/11 were due to a safety-related failure." UL is the company that certified the steel components used in the construction of the World Trade Center towers. Kevin Ryan was subsequently fired from his job. 
- Van Romero, Vice President for Research and Economic Development at New Mexico Institute of Mining and Technology, a major authority on explosions' effects on buildings, has said, "My opinion is, based on the videotapes, that after the airplanes hit the World Trade Center there were some explosive devices inside the buildings that caused the towers to collapse." Romero has since retracted his belief, later stating, "Certainly the fire is what caused the building to fail." ("Explosives Planted in Towers, New Mexico Tech Expert Says", Albuquerque Journal, September, 2001).
- Former Assistant Secretary of the Treasury under President Reagan, Paul Craig Roberts, expressed his doubt about the common account in the following statement: "I know many qualified engineers and scientists have said the WTC collapsed from explosives. In fact, if you look at the manner in which it fell, you have to give their conclusions credibility."
- In The New Pearl Harbor, former theology and philosophy Professor David Ray Griffin presents a litany of observations he says are consistent with controlled demolition, including sudden onset, straight down symmetry, pulverization, horizontal ejection, dust clouds, squibs, and molten metal. He says that since 2 WTC collapsed first, when it appeared most of the jet fuel was ignited on impact outside the tower, the mechanism of collapse is questionable. Additionally, he argues the impact of the second aircraft was not as precise as the first, suggesting less fuel would have burned in the central support area.
- On June 13, 2005, the Washington Times reported that former Chief Economist for the Department of Labor during President George W. Bush's first term, Morgan Reynolds, said the common account of the WTC collapse is "bogus" and suggests a controlled demolition destroyed the Twin Towers and adjacent Building No. 7. He also questioned the involvement of commercial jets stating that "North Tower's hole wasn't big enough for a Boeing 767." 
- Jimmy Walter, who believes that 9/11 was the work of a government conspiracy and has run ads in New York requesting that the investigation into 9/11 be reopened- suggests that, "[the] aircraft were robot planes; the passengers were mainly military contractors; the aircraft were only 10 to 25 per cent full, while all other planes that day were booked out."
- Recently, actor Charlie Sheen gave an interview on GGN Radio Network's "The Alex Jones Show," in which he suggested that the federal government was covering up what "really" happened. "It seems to me like 19 amateurs with box cutters taking over four commercial airliners and hitting 75 percent of their targets, that feels like a conspiracy theory. It raises a lot of questions," Sheen said. He also expressed disbelief over how American Airlines Flight 77 hit the Pentagon, and said the collapse of the Twin Towers looked like a "controlled demolition."
7 World Trade Center
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.
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 researchers say these examples show that an explanation of the collapse of WTC7 is quite difficult, unless controlled demolition is introduced to explain it.
9/11 researchers have proposed the idea Building Seven 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. The FEMA report describes a collapse timeline of 37 seconds.
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 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. 
The damage and fire
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 on 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 7 WTC. 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 7 WTC 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 2006.  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."
The Silverstein statement
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 WTC7:
- 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.' And they made that decision to pull and then we watched the building collapse. 
Some critics of the official theory have said that the term "pull" is industry jargon for planned demolition and that Silverstein's remark exposes his assent to demolishing the building. 
Silverstein's spokesperson, Mr. Dara McQuillan, later explained:
- 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.
Researcher Jim Hoffman disputes the assertion that "pull" is industry jargon. A Google search, he says, fails to uphold the assertion. For this and other reasons, he says, the case built from Mr. Silverstein's statement is "extremely weak." He concludes: "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. . ." 
Controlled demolition experts at ImplosionWorld.com refute this, saying that they have never heard the term used to refer to the demolition of a building. They also debunk the theory that controlled demolition was used to bring down 7 World Trade Center.
Questions about war games on the morning of 9/11
On the morning of 9/11, 50 minutes before Flight 77 crashed into the Pentagon, the National Reconnaissance Office had scheduled an exercise simulating the crashing of an aircraft into their building, four miles from Dulles airport. The National Reconnaissance Office is responsible for operating US reconnaissance satellites. At 9:25 an order had been issued by the Federal Aviation Agency grounding all aircraft, including military and law enforcement aircraft.
Some researchers questioning the official account of 9/11 assert that government and military exercises point to a cover-up. There were a number of drills being performed on the morning of 9-11. US Rep. Cynthia McKinney, economist Michel Chossudovsky, and publisher/editor Michael Ruppert of From the Wilderness are a few of the individuals who have questioned these exercises.
- Northern Vigilance: a yearly Air Force drill simulating a Russian attack, in which defense aircraft normally patrolling the Northeast are re-deployed to Canada and Alaska.
- Vigilant Guardian: a NORAD exercise posing an imaginary crisis to North American Air Defense outposts nationwide with a simulated air war and an air defense exercise simulating an attack on the United States.
- National Reconnaissance Office emergency response drill of a small aircraft crashing into its own headquarters.
- Tripod II, a FEMA drill simulating a biowarfare attack in New York City, was to take place on September 12th. FEMA set up a command post for this exercise at Pier 29 on September 10th.
It is theorized that with these multiple training scenarios being carried out that NORAD, FAA and other military personnel would have been confused in the event of a real attack. McKinney has twice questioned Defense Secretary Donald Rumsfeld about these 9/11 war games during his testimony before Congress. 
The President's behavior
President Bush was promoting the passage of his education plan at Emma E. Booker Elementary School on the morning of September 11th.
Allan Wood and Paul Thompson have questioned the President's behavior after being told that the nation was under attack. They think it's likely that he would have been taken to safety at once, presuming that he too would be a possible target of a terrorist attack. He remained in the classroom for another 5 minutes.
Did George W. Bush see the first plane hit?
On December 4, 2001, at a townhall meeting in Orlando, Florida, in response to a question from a third grader, President Bush described his reaction to the initial 9-11 news as follows:
"I was sitting outside the classroom waiting to go in, and I saw an airplane hit the tower -- the TV was obviously on. And I used to fly, myself, and I said, well, there's one terrible pilot. I said, it must have been a horrible accident.
"But I was whisked off there, I didn't have much time to think about it. And I was sitting in the classroom, and Andy Card, my Chief of Staff, who is sitting over here, walked in and said, 'A second plane has hit the tower, America is under attack.'"
A month and a day later, at a townhall meeting in Ontario, California, President Bush described his experience like this:
"Anyway, I was sitting there, and my Chief of Staff -- well, first of all, when we walked into the classroom, I had seen this plane fly into the first building. There was a TV set on. And you know, I thought it was pilot error and I was amazed that anybody could make such a terrible mistake. And something was wrong with the plane, or -- anyway, I'm sitting there, listening to the briefing, and Andy Card came and said, 'America is under attack.'"
These observations make it appear that George Bush had access to coverage of the attacks that the public did not. As some have pointed out, George Bush could not have seen the first plane hit the tower live on commercial television, since it was a surprise attack and no television station was covering that area when the first plane hit. , . A White House spokesperson said that the president's comment was "just a mistaken recollection" .
See also the morning of September 11th.
Other points of interest
- US Representative Cynthia McKinney led a Capitol Hill hearing on July 23, 2005, into "what warnings the Bush administration received before the terrorist attacks of September 11, 2001." Panelist and former CIA official Melvin Goodman was quoted as saying "Congresswoman McKinney is viewed as a contrarian and I hope someday her views will be considered conventional wisdom." Many 9/11 researchers testified at the hearing, including Michael Ruppert, Peter Dale Scott, David Ray Griffin, Wayne Madsen and several others. 
- Between 1993 and 2000, Marvin Bush, President Bush's brother was a principal in a company that provided security for both The World Trade Center and United Airlines. According to an article by David Ray Griffin "from 1999 to January of 2002 their cousin Wirt Walker III was the CEO " . According to its president CEO, Barry McDaniel, the company had an ongoing contract to handle security at the World Trade Center "up to the day the buildings fell down". This last statement has been used by some conspiracy theorists to say that the contract "expired" on September 11, 2001. Barbara Bush allegedly confirmed this theory in her book Reflections (ISBN 0743223594) also stating 9/11 was the day the contract expired. However, no specific quote is provided to support this allegation, and a search for the words "contract" or "expired" yields no results. Mr. Bush was also a former director and now is an advisor to the board of directors to a firm HCC Insurance Holdings, Inc that had what it called a small participation in the World Trade Center property insurance coverage and some of the surrounding buildings.  Marvin Bush was on a subway under Wall Street when the attacks happened. 
- Iranian President Mahmoud Ahmadinejad in a letter to President Bush said, “September eleven was not a simple operation. Could it be planned and executed without coordination with intelligence and security services – or their extensive infiltration? Of course this is just an educated guess. Why have various aspects of the attacks been kept secret? Why are we not told who botched their responsibilities? And, why aren’t those responsible and the guilty parties identified and put on trial?” He also wrote, “Some believe that the hype paved the way-- and was the justification-- for an attack on Afghanistan”.
- Although it had distanced itself from their brother and former company employee, The Saudi Binladin Group's corporate website, , expired on September 11, 2001, the same day as the attacks in the United States. Several websites cited in this article use this fact to suggest foreknowledge of the attacks.[ ]
- The Washington Post reported in its August 3, 2006 edition that "For more than two years after the attacks, officials with NORAD and the FAA provided inaccurate information about the response to the hijackings in testimony and media appearances" and that "Some staff members and commissioners of the Sept. 11 panel concluded that the Pentagon's initial story of how it reacted to the 2001 terrorist attacks may have been part of a deliberate effort to mislead the commission and the public" and that "Suspicion of wrongdoing ran so deep that the 10-member commission, in a secret meeting at the end of its tenure in summer 2004, debated referring the matter to the Justice Department for criminal investigation. In the end, the panel agreed to a compromise, turning over the allegations to the inspectors general for the Defense and Transportation departments, who can make criminal referrals if they believe they are warranted". Sources told the Post this was done to hide a bungled Pentagon response 
Claims that some of the supposed hijackers are still alive
Initial news reports shortly after 9/11 indicated that some of the supposed hijackers were alive, fueling speculation that others were responsible .
The BBC News reported on September 23, 2001, that some of the people named by the FBI as hijackers, killed on the crashes, were actually alive and well.
One of the supposed hijackers was Waleed al-Shehri, and he was supposedly found in Casablanca, Morocco.
- However, the al-Shehri's father says he hadn't heard from his sons in ten months prior to September 2001. An ABC News story in March 2002 repeated this, and during a report entitled "A Saudi Apology" for Dateline NBC on Aug 25, 2002, NBC's reporter John Hockenberry traveled to 'Asir, where he interviewed the third brother Salah who agreed that his two brothers were dead and claimed they had been "brainwashed".
- Furthermore, another article explains that the pilot who lives in Casablanca was named Walid al-Shri (not Waleed M. al-Shehri) and that much of the BBC information regarding "alive" hijackers was incorrect according to the same sources used by BBC.
- A man with the same name as Abdulaziz Al Omari turned up alive in Saudi Arabia, saying that he had studied at the University of Denver and his passport was stolen there in 1995. The name, origin, birth date, and occupation were released by the FBI, but the picture was not of him. "I couldn't believe it when the FBI put me on their list", he said. "They gave my name and my date of birth, but I am not a suicide bomber. I am here. I am alive. I have no idea how to fly a plane. I had nothing to do with this."  This individual was not the same person as the hijacker whose identity was later confirmed by Saudi government interviews with his family, according to the 9/11 Commission Report.[ ]
- On 23 September, 2001, the BBC and The Telegraph  reported that a person named Saeed al-Ghamdi was alive and well. His name, birth date, origin, and occupation were the same as those released by the FBI, but his picture was different. He says that he studied flight training in Florida flight schools from 1998 to 2001. The journalist involved with the story later admitted "No, we did not have any videotape or photographs of the individuals in question at that time."
- After the attacks, reports began emerging saying that al-Mihdhar was still alive. On September 19, the FDIC distributed a "special alert" which listed al-Mihdhar as alive. The Justice Department says that this was a typo.
The BBC and The Guardian have since reported that there was evidence al-Mihdhar was still alive and that some of the other hijackers identities were in doubt. This was commented on by FBI director Robert Mueller.
Theories as to why members of the US government would have allowed the attacks to occur, perpetrated the attacks, and/or obstructed the investigation generally involve one or more of the following:
- Michel Chossudovsky in an article entitled "The Criminalization of the State" suggests a simple motive in a plan for a New World Order. This particular theory takes root in a David Rockefeller Statement to the United Nations Business Council in September 1994: We are on the verge of a global transformation. All we need is the right major crisis and the nations will accept the New World Order. 
- An article on whatreallyhappened.com entitled "The 9/11 Reichstag Fire" suggests that the Project for the New American Century (PNAC) may have been responsible. It cites as evidence a statement from page 51 of a document titled 'Rebuilding America's Defenses: Strategy, Forces and Resources For a New Century' published by PNAC: Further, the process of transformation, even if it brings revolutionary change, is likely to be a long one, absent some catastrophic and catalyzing event - like a new Pearl Harbor.
- The Web site OilEmpire.us proposed that 9/11 was arranged by the U.S. government in order to benefit the arms manufacturing and oil industries .
- The Web site 9-11 Review listed several other benefits of the attacks as possible motives, including Mayor Rudolph Giuliani and President Bush's surge in popularity, Halliburton's defense contracts for the wars in Afghanistan and Iraq, and a $3.6 billion insurance payout to the owner of the World Trade Center, Larry Silverstein .
Another less publicized theory, yet very much in line with the Rockefeller quote above, is the claiming of the Holy Land. 9/11 provided an excuse to take the "New Babylon" from Saddam Hussein, who had already begun the process of rebuilding Babylon.[ ]
Claims related to the Saudi royal family and other Saudi government officials
Of the increasing instances in which 9/11 conspiracy theories have been discussed in the mainstream media, two instances occurred in 2004 involving Howard Dean and Michael Moore. Howard Dean, who was then the front runner for the Democratic nomination for President stated that he had heard of some people theorizing that the Saudi Royal family were behind the attacks. Though he made the comments somewhat sympathetically, he did state that this was not his personal belief. Later, he would also comment that he believed Osama bin Laden needed to be "proven guilty" in a court of law, a remark some saw as a subtle indication Dean did not presently believe bin Laden's guilt was self-evident. Such 9/11 statements were often cited as an important reason for the failure of his candidacy.
Also in 2004, filmmaker Michael Moore released the controversial documentary film Fahrenheit 9/11, in which many aspects of September 11th were discussed from a point of view skeptical of the official story. The film suggests that the business relationship between the Bush family and the House of Saud led to a conflict of interest, if not an outright conspiracy which hindered both the prevention of the attack and the investigation of it.
An article in the December 7-13, 2005 issue of The Village Voice reported "The Joint Inquiry Into Intelligence Community Activities Before and After the Terrorist Attacks of September 11, 2001, which was released in late 2002, included 28 pages that were blanked out, apparently concerning the possible role of Saudi government officials". Another article from the same issue discussing the 9/11 Commission reported "The Joint Inquiry traced the flow of money from the Saudi royal family and government institutions to a Saudi spy in California who had contact with the hijackers. The commission found Saudi Arabia blameless although behind closed doors the staff is said to have demanded an airing of the situation."
Claims related to Jews and Israel
4,000 Jewish employees did not attend work at the WTC on 9/11
This claim made by Al-Manar, the television station of Hezbollah, has been repeated by a wide variety of other sources, such as Amiri Baraka. The original Al-Manar claim, posted September 17, 2001 on the English language version of Al-Manar's website, was:
"With the announcement of the attacks at the World Trade Center in New York, the international media, particularly the Israeli one, hurried to take advantage of the incident and started mourning 4,000 Israelis who work at the two towers. Then suddenly, no one ever mentioned anything about those Israelis and later it became clear that they remarkably did not show up in their jobs the day the incident took place. No one talked about any Israeli being killed or wounded in the attacks."
Al-Manar further claimed that "Arab diplomatic sources revealed to the Jordanian al-Watan' newspaper that those Israelis remained absent that day based on hints from the Israeli General Security apparatus, the Shabak". It is unclear whether al-Watan (a minor Jordanian newspaper with no website) made these claims or who (if anyone) the alleged "Arab diplomatic sources" were. No independent confirmation has been produced for this claim.
In some versions of the story circulated on the Internet, the title was changed to "4,000 Jewish Employees in WTC Absent the Day of the Attack" from its original "4000 Israeli Employees in WTC Absent the Day of the Attack", spawning a further rumor that not only Israeli but all Jewish employees stayed away. On September 12 an American Web site called "Information Times" published an article with the headline "4,000 Jews Did Not Go To Work At WTC On Sept. 11," which it credited to "AL-MANAR Television Special Investigative Report." According to Slate.com, "The '4,000 Jews' page is easily forwarded as e-mail, and this may explain the message's rapid dissemination." The rumour was also published; according to the United States Department of State "Syria's government-owned Al Thawra newspaper may have been the first newspaper to make the "4,000 Jews" claim... its September 15th edition falsely claimed 'four thousand Jews were absent from their work on the day of the explosions.' "
There were a total of 5 Israeli deaths in the attack (Alona Avraham, Leon Lebor, Shay Levinhar, Daniel Lewin, Haggai Sheffi), of which 3 were in the World Trade Center and 2 were on the planes. (4 are listed as American on most lists, presumably having dual citizenship.)
Early estimates of Israeli deaths, as of the total death toll and the death toll for other countries' citizens (e.g. India) proved substantially overestimated. George W. Bush cited the figure of 130 in his speech on September 20th.
A total of 2,071 occupants of the World Trade Center died on September 11, among the 2,749 victims of the WTC attacks. According to an article in the October 11, 2001, Wall Street Journal, roughly 1,700 people had listed the religion of a person missing in the WTC attacks; approximately 10% were Jewish. A later article, in the September 5, 2002, Jewish Week, states, "based on the list of names, biographical information compiled by The New York Times, and information from records at the Medical Examiner's Office, there were at least 400 victims either confirmed or strongly believed to be Jewish." This would be approximately 15% of the total victims of the WTC attacks. A partial list of 390 Cantor Fitzgerald employees who died (out of 658 in the company) lists 49 Jewish memorial services, which is between 12% and 13%. This 10-15% estimate of Jewish fatalities tracks closely with the percentage of Jews living in the New York area. According to the 2002 American Jewish Year Book, 9% of the population of New York State, where 64% of the WTC victims lived, is Jewish. A 2002 study estimated that New York City's population was 12% Jewish. Forty-three percent of the WTC victims lived in New York City. Thus, the number of Jewish victims correlates very closely with the number of Jewish residents in New York. If 4,000 Jews had not reported for work on September 11, the number of Jewish victims would have been much lower than 10-15%.
The figure "4,000" was probably taken by Al-Manar from a Jerusalem Post article of September 12 (p. 3) which said "The Foreign Ministry in Jerusalem has so far received the names of 4,000 Israelis believed to have been in the areas of the World Trade Center and the Pentagon at the time of the attack." This number was obviously not (as Al-Manar claimed) restricted to employees; in fact, , minister of administrative affairs for the Israeli consulate and mission in New York, said on September 14 "that there might have been up to 100 Israeli citizens working in the World Trade Center". 
Sharon was warned by Shabak to stay away from New York
Al-Manar the official television station of Hezbollah, also made related claims that then-prime minister Ariel Sharon was warned to stay away from New York:
- Suspicions had increased further after Israeli newspaper Yediot Aharonot revealed that the Shabak prevented Israeli premier Ariel Sharon from traveling to New York and particularly to the city's eastern coast to participate in a festival organized by the Zionist organizations in support of Israel. Aharon Bernie, the commentator at the newspaper, brought up the issue and came up with a negative conclusion, saying "no answer". He then asked about the clue behind the Shabak's position in preventing Sharon's participation, and again without giving an answer.
Detractors claim that this theory does not hold up to examination. A pro-Israel rally led by the United Jewish Communities, expected to include 50,000 people, had been planned for September 23, 2001. Ariel Sharon had been scheduled to speak there,  but it was canceled on September 12.  According to The Forward, Sharon was still scheduled to speak there at the time of cancellation. 
There was no article in Yediot Aharonot that contains the information cited by Al-Manar, nor was there a columnist named Aharon Bernie. There is an Israeli reporter named Aharon Barnea of Israel's Channel 2 News whose wife Amalia works for Yediot Aharonot;  it has been speculated that "Aharon Bernie" arose as a misspelling of this name. 
Mossad connection to filming of 9/11 attacks with "puzzling behavior"
This claim formed part of the Al-Manar report mentioned above. The claim is that:
- For its part, the Israeli Ha'aretz' newspaper revealed that the FBI arrested five Israelis four hours after the attack on the Twin Towers while filming the smoking skyline from the roof of their company's building. The FBI had arrested the five for "puzzling behavior". They are said to have been caught videotaping the disaster in what was interpreted as cries of joy and mockery. 
This claim was substantially correct. Yossi Melman had reported to that effect in Haaretz on September 17 2001,  using the words "puzzling behavior" and "what was interpreted as cries of joy and mockery." Several mainstream Western media groups researched this. On June 21, 2002, ABC published a report that five Israelis seen filming the events of September 11 in New York and looking "happy" were subsequently arrested, claiming (on The Forward's authority) that the "FBI concluded that two of the men were Israeli intelligence operatives" but had no advance knowledge of 9/11.
The Forward had reported the five as a possible Mossad surveillance operation conducted not against the US but against "radical Islamic networks suspected of links to Middle East terrorism." Mossad was known to have been infiltrating Al Qaeda at the time. Sivan Kurzberg, Paul Kurzberg, Yaron Shmuel, Oded Ellner and Omer Marmari, the five Israelis who were kept in custody in the federal Metropolitan Detention Center in Sunset Park for approximately two months were eventually deported back to Israel on November 20-21, 2001.  Ellner and others in the prison have complained of abuse by prison guards. 
Israel advance knowledge
An ambiguous claim was made that the Mossad had been shadowing the perpetrators and had advance warning of these attacks but failed to share it. [ ]
Supporters of this claim sometimes cite a Washington Post article of September 28, 2001, according to which "Officials at instant-messaging firm Odigo confirmed today that two employees received text messages warning of an attack on the World Trade Center two hours before terrorists crashed planes into the New York landmarks."[ ] CNN also reported this but added that "Alex Diamandis, vice president for sales and marketing with Odigo Inc., said there was nothing specifically about the attacks in the message, but he said it was suspicious in nature, especially because of its timing."[ ] The Israeli newspaper Haaretz also published reports regarding these warnings. [ ]
According to a September 16, 2001 story in The Daily Telegraph, Israel had sent two Mossad agents to Washington in August to warn both the FBI and CIA in August of an imminent large-scale attack involving a large cell of up to 200 terrorists. An unnamed senior Israeli security official was quoted as saying "They had no specific information about what was being planned but linked the plot to Osama bin Laden and told the Americans that there were strong grounds for suspecting Iraqi involvement."
Less common theories
- NewsMax.com [lie-filled GOP rag, home of Jeff Gannon criminal fraud] reported that people within and outside the U.S. government believed that then Iraqi leader Saddam Hussein conspired in the 9/11 attacks and the Oklahoma City Bombing . The theory extended from the one advanced by investigative journalist Jayna Davis in her book The Third Terrorist linking Hussein to the Oklahoma City Bombing. It was discussed in an op-ed piece in the Wall Street Journal .
- Judi McLeod of Canada Free Press suggested the possible involvement of the mafia. 
While discussion and coverage of these theories is mainly confined to internet chat sites, a number of mainstream news outlets around the world have covered the issue.
In the July 2006 edition of the Norwegian version of Le Monde diplomatique, the headline story asked, "11 September : An Inside Job?" and recensed the various theories discussing the official US version of 9/11, withholding any truth judgment on them .
- In an August 2004 Zogby International poll, half (49.3%) of New York City residents and 41% of New York citizens overall believe the US Government "knew in advance that attacks were planned on or around September 11, 2001, and that they consciously failed to act." 
- In a May 2006 Zogby International poll, 44% of Americans believe Bush exploited the Sept. 11th attacks to justify the invasion of Iraq; 42% of Americans believe the US government and 9/11 Commission are covering up certain events of 9/11; 43% of Americans are not aware that 7 WTC collapsed on 9/11; 45% of Americans believe "Congress or an International Tribunal should re-investigate the attacks, including whether any US government officials consciously allowed or helped facilitate their success"; 45% of Americans believe the US's media are doing a negative job, "including their coverage of victim families' unanswered questions" 
- A July 2006 Scripps Howard/Ohio University poll found that 36% of the American public suspects that federal officials assisted in the 9/11 terrorist attacks or took no action to stop them so the United States could go to war in the Middle East. The poll found that 16 percent of Americans speculate that secretly planted explosive brought down the Twin Towers and that 12 percent speculate that a cruise missile hit the Pentagon. 
Critics of these alternative theories claim they are a form of conspiracism common throughout history after a traumatic event in which conspiracy theories emerge as a mythic form of explanation (Barkun, 2003).
The German magazine Der Spiegel summarily dismissed all skeptical accounts of the 9/11 attacks as a "panoply of the absurd", stating "as diverse as these theories and their adherents may be, they share a basic thought pattern: great tragedies must have great reasons."
- September 11, 2001 attacks
- New World Order (conspiracy)
- Conspiracy theory
- Media manipulation
- Osama bin Laden tapes
- Operation Northwood
- Researchers questioning the official account of 9/11
- The Lone Gunmen (pilot episode)
- 9/11 Revisited by BYU Professor Steven E. Jones
- Pentagon Strike
- 9/11 Guilt: The Proof is in Your Hands
- 911 In Plane Site
- Loose Change
- ^ Bush, George W. "Remarks by the President to United Nations General Assembly". November 10, 2001.
- ^ PrisonPlanet.com. "In July 2001, Alex Jones Warned of Globalist Plan to Use Bin Laden to Attack America". August 26, 2004 
- ^ Sales, Nancy Jo. "Click Here For Conspiracy", Vanity Fair July 9, 2006 
- ^ Eggen, Dan. "9/11 Panel Suspected Deception by Pentagon", Washington Post, Wednesday, August 2, 2006, page A03.
- ^ Sales, Nancy Jo. "Click Here For Conspiracy", Vanity Fair July 9, 2006 
- ^ Meacher, Michael (2003). This war on terrorism is bogus. The Guardian Unlimited - Comment. Guardian Newspapers Limited. Retrieved on .
- ^ Crogan, Jim (2002). Another FBI Agent Blows the Whistle. LA Weekly News. LA Weekly, LP. Retrieved on .
- ^ Grigg, William Norman (2002). Did We Know What Was Coming?. The New American magazine. American Opinion Publishing Incorporated. Retrieved on .
- ^ The Associated Press (2005). More remember Atta ID’d as terrorist pre-9/11. MSNBC News - US Security. MSNBC.com. Retrieved on .
- ^ Kirk, Michael; Jim Gilmore (2002). The Man Who Knew. Transcript of Frontline program #2103. WGBH Educational Foundation. Retrieved on .
- ^ Willie Brown got low-key early warning about air travel. Matier and Ross. San Francisco Chronicle (2001). Retrieved on .
- ^ Shot from street level of South Tower collapsing (Macromedia Flash video). CameraPlanet 911 Archive/Google Video (2001).
- ^ McAllister, Therese, ed. (2002). "World Trade Center Building Performance Study" (PDF). Retrieved on .Chapter 2, Section 126.96.36.199, page 34.
- ^ ShyamSunder, S. (2003). Progress Report on the Federal Building and Fire Safety Investigation of the World Trade Center Disaster (pdf). National Institute of Standards and Technology.Volume 4, Appendix H, Section H.9, page 43, cited in Greening, Frank (2006), unpublished. Available at: http://www.911myths.com/WTCTHERM.pdf. Retrieved on 2006-03-06.
- ^ Barnett, Jonathan; Ronald R. Biederman, R.D. Sisson, Jr. (2002). Limited Metallurgical Examination (pdf). FEMA 403 -- Appendix C.6, Suggestions for Future Research. Federal Emergency Management Agency. Retrieved on . - "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."
- ^ http://911myths.com/Sulfur.pdf
- ^ Killough-Miller, Joan (2002). The "Deep Mystery" of Melted Steel. WPI Transformations. Worcester Polytechnic Institute. Retrieved on . - "Have environmental pollutants increased the potential for eutectic reactions? 'We may have just the inherent conditions in the atmosphere so that a lot of water on a burning building will form sulfuric acid, hydrogen sulfide or hydroxides, and start the eutectic process as the steel heats up,' Biederman says. He notes that the sulfur could also have come from contents of the burning buildings, such as rubber or plastics. Another possible culprit is ocean salts, such as sodium sulfate, which is known to catalyze sulfidation reactions on turbine blades of jet engines. 'All of these things have to be explored,' he says."
- ^ Toreki, Rob (2006). The Thermite Reaction. The General Chemistry Demo Lab. Interactive Learning Paradigms Incorporated.. Retrieved on .
- ^ FEMA report on Bankers Trust Building (pdf). Columbia University Civil Engineering & Engineering Mechanics Department (2003).
- ^ Video about ejected girders by David Chandler of 911SpeakOut.org (Macromedia Flash video). Google Video (2003).
- ^ 
- ^ anonymous. "Sheen: What 9/11 Hijackers?", The New York Post, N.Y.P. Holdings, Inc., , p. 10. Retrieved on .
- ^ Popular Mechanics, March 2005 [http://www.popularmechanics.com/science/defense/1227842.html?page=1&c=y 9/11: Debunking The Myths ] Accessed August 14, 2006
- ^ McAllister, Th. (2002). World Trade Center Building Performance Study (pdf) pp. 19. Federal Emergency Management Agency (FEMA). Retrieved on .
- ^ Glanz, James (2001). Diesel suspected in 7 WTC collapse. Across the nation. Chicago Tribune. Retrieved on .
- ^ Blanchard, Brent (2006, August 8). A critical analysis of the collapse of WTC towers 1, 2 & 7 from an explosives and controlled demolition industry viewpoint. ImplosionWorld.com.
- ^ FOIA request. Judicial Watch.
- ^ Agency planned exercise on Sept. 11 built around a plane crashing into a building. Associated Press.
- ^ The Day the FAA Stopped the World. Time.
- ^ Paltrow, S. (2004) "Day of Crisis: Detailed Picture of U.S. Actions on Sept. 11 Remains Elusive." Wall Street Journal March 22
- ^ http://www.newsmax.com/archives/articles/2002/9/9/111622.shtml
- ^ http://www.opinionjournal.com/extra/?id=110002217
- ^ http://www.canadafreepress.com/2005/cover071105.htm
- ^ http://www.eurozine.com/articles/2006-07-21-bredesen-en.html
- ^ Cziesche, Dominik; Jürgen Dahlkamp, Ulrich Fichtner, Ulrich Jaeger, Gunther Latsch, Gisela Leske, Max F. Ruppert (2003). Panoply of the Absurd. Der Spiegel. Der Spiegel. Retrieved on .
- ^ Popular Mechanics, March 2005 [http://www.popularmechanics.com/science/defense/1227842.html?page=1&c=y 9/11: Debunking The Myths ] Accessed August 14, 2006
- The 9/11 Commission Report
- The 9/11 Commission Report: Omissions And Distortions - David Ray Griffin
- 9/11: The Big Lie - Thierry Meyssan
- 9/11 Revealed : The Unanswered Questions - Rowland Morgan and Ian Henshall
- Crossing the Rubicon - Michael Ruppert
- Divided We Stand: A Biography of New York's World Trade Center
- The Five Unanswered Questions About 9/11 - James Ridgeway
- Inside 9-11 : What Really Happened - Der Spiegel Magazine
- Pentagate - Thierry Meyssan
- Waking up from our Nightmare: The 9/11 Crimes in New York City - Don Paul and Jim Hoffman, ISBN 9430960512
- Barkun, Michael (2003). A Culture of Conspiracy: Apocalyptic Visions in Contemporary America. University of California Press. ISBN 0520238052.
- Laurent, Eric (2004). La face cachée du 11 septembre. Plon. ISBN 2259200303.
- 9/11 Synthetic Terror: Made in USA, by Webster Griffin Tarpley
- The New Pearl Harbor - David Ray Griffin
- Der Spiegel (2002). Inside 9-11: What Really Happened. St. Martin's Press. ISBN 0312306210.
- Debunking 9/11 Myths: Why Conspiracy Theories Can't Stand Up to the Facts - The Editors of Popular Mechanics. ISBN 158816635X
- Final report of the "National Commission on Terrorist Attacks Upon the United States" (9-11 Commission), chaired by Thomas H. Kean
- Cynthia McKinney's July 2005 Congressional Briefing on 9/11
- June 1, 2001, directive from the Joint Chiefs of Staff changing rules on intercepting hijacked planes
- Descriptions of and evidence for various conspiracy theories
Mainstream news organizations
- Conspiracy Theories. CBC Television. Retrieved on .
- 9/11 conspiracy theorists energized Five years later, purveyors claim academic momentum. CNN.com. Retrieved on .
- 9-11 Research An Attempt to Uncover the Truth About September 11th, 2001. Retrieved on .
- Alex Jones Infowars. Retrieved on .
- Former Top German Minister Rejects Official Story Of 911 Attacks. www.ratical.org. Retrieved on .
- Bush: The Ignored Warning That Will Come To Haunt Him. Retrieved on . by Gordon Thomas
- Information on 9/11 Wargames. oilempire.us. Retrieved on .
- Scholars for 9/11 Truth. Retrieved on .
- 9/11 Conspiracy: Finding Truth. RINF. Retrieved on .
- Free-Falling Bodies Simple Physics Reveals The Big Lie Collapse Theory Fails Reality Check. 911blimp.com. Retrieved on .
- Why Indeed Did the WTC Buildings Collapse?. BYU.edu. Retrieved on .
- The 911 Movement. Retrieved on .
- NIST and the World Trade Center. Retrieved on .
- 911 investigations. Retrieved on . Document base dedicated to the September 11th 2001 attacks
- Charlie Sheen talks about September 11th. CNN, Your Tube. Retrieved on . Charlie Sheen talks about September 11th
- Question911.com. Retrieved on . Free DVD movie downloads discussing September 11th attack evidence
- 9/11 Mysteries The show went to Hollywood!. Retrieved on . Movie on 9/11 questions
- The WTC Conspiracy. Telepolis. Retrieved on . (German)
- Loose Change. Retrieved on . Film questioning the official story
- The 9/11 Conspiracy: A Skeptic's View by Ernest Partridge. , commondreams.org. Retrieved on . Article sympathetic to LIHOP theories but skeptical of MIHOP theories
- Picking Up Where Partridge Leaves Off:Researchers Address a 9/11 Skeptic by Victoria Ashley and Jim Hoffman. Retrieved on . Pro MIHOP rebuttle to above article
- How Did United Flight 93 Crash?. flight93crash.com. Retrieved on .
- Flight 93 Ordered Shot Down. dcdave.com. Retrieved on .
- Problems With the ASCE Report On The Pentagon Cast Further Doubt on 757 Story. bedoper.com. Retrieved on .
- 911blogger. 911Blogger.com. Retrieved on . Latest news and research
- American-Freedom.org. Retrieved on . News, research, information, blog, links, and a vast video library
Debunking conspiracy claims
- Debunking 9/11 Conspiracy Theories Evidence against Controlled Demolition and its most widely held myths.
- Journal of Debunking 9/11 Conspiracy Theories The Journal of Debunking 9/11 Conspiracy Theories is a free online publication dedicated to educating the public on the events surrounding 9/11.
- Mike J Wilson's Flight 77 Case Study Computer animation with photos and videos. You can also download the 3D models used.
- U.S. Department of State "How To Identify Misinformation"
- U.S. Department of State refutes 9/11 conspiracy book.
- U.S. Department of State links to refutations of various 9/11 conspiracy theories.
- Scientific American 9/11 Article Skeptical of Conspiracy Theories by Michael Shermer
- Snopes.com answer to the rumors about the Pentagon attack Skeptical review of David Ray Griffin book, The New Pearl Harbor (and Griffin's response)
- Indications of the Imminent Collapse of the WTC Disproves Controlled Demolition Theory 9/11 Controlled Demolition Theory Debunked
- Refutes various elements. Strong focus on refuting Mike Ruppert's timeline
- David Ray Griffin and Chip Berlet debate 9/11 issues on Democracy Now!
- 911 Myths articles by UK software developer and freelance writer Mike Williams on a wide range of topics
- Jacobson, Mark (March 27,2006). "The Ground Zero Grassy Knoll". New York Magazine.
- Flight 77 Did Hit The Pentagon - Attempted debunking from AboveTopSecret.com
- Anti-Defamation League, "Unraveling anti-semitic 9/11 conspiracy theories"
- Venezuelan Government To Launch International 9/11 Investigation
- Op ed piece from April 28th edition of Newsday by James P. Pinkerton debunking alternative theorists while supporting Incompetence Theory 
- The 9/11 X-Files article from The Nation
- When 9/11 Conspiracy Theories Go Bad by David Corn
- 9/11 Denial by James S. Robbins
- "The Truth About 911" - editorial cartoon mocking conspiracy theories
- "There is no 9/11 conspiracy you morons" - An argument against 9-11 conspiracy theories by the popular internet humorist Maddox (writer).