The terrorist airplane collisions did NOT cause the 3 buildings to collapse on 9/11, felling the famous Twin Towers & Building 7 of the WTC. An article I wrote a few days after 9/11 and tried to publish as a newspaper editorial stated explosions did it, and these facts have been since examined thousands of times & shown to be the only consistent explanation. Presidential candidates should address these facts, exposing the errors that has been written into hundreds of government documents.
Evidence for high temperatures and explosive use was posed with the potential involvement of thermite by Jones in 2006, and evidence for very high temperatures in the WTC dust, much higher than fire can produce was published by a group of us in 2008.[2,3] A strong implication of the use of nano-thermite was found shortly afterward.
Thermite is a mixture of aluminum and iron oxide that when heated to high temperatures (above 900° C) undergoes a very strong exothermic (heat-releasing) reaction to produce a very incendiary device. Nano-thermites are new level of finely mixed crystals of these reactants that have a lower setoff temperature and more explosive reaction. The extensive evidence found for very-small bits of explosive nano-thermite prevalent in the WTC dust for all 3 collapsed buildings was published in early 2009.[5,6]
What the internation group of scientists, headed by Danish chemist Neils Harrit, found was an active thermitic material in the form of microscopic red-gray chips (see Figure 1) detected using a scanning electron microscope (SEM). X-ray energy dispersion graphs were used to identiy the individual elements. The gray chips were found to be primarily iron (Fe) and oxygen (O), with a small bit of carbon (C) mixed in. The red layers were nanocomposites with a high aluminum (Al) and silicon (Si) content as well as Fe, O, in a C matrix. The number of Fe atoms was found to be about 2/3 the number of O atoms, indicating the Fe is apparently oxidized in the Fe2O3 state. Al was present 3 times as frequent in the red chips as O, showing it apparently was not oxidized.
Figure 1. Fragments of nano-Thermite found as microscopic red-gray chips throughout the dust at the World Trade Center. The gray surfaces were identified as primarily iron oxide (Fe2O3) covering the outside of the chips, and the red chips were identified as aluminum (Al) mixed with silicon (Si) and Fe2O3, clearly explosive at higher temperatures.
The red chips clearly contain nano-thermite, a nano-mixture of Al and Fe2O3 ripe for the very energetic chemical reaction 2Al + Fe2O3 -> Al2O3 + 2Fe . For ordinary thermite which the Army has used since World War II the chemical reaction takes place above 900°C and it is typically used as an indendiary device. However, numerous laboratory test of this nano-thermite showed that reaction took place at 435°C or below, and the reaction was very explosive, quickly producing temperatures of 3000°C. The Fe-rich spherules described in their paper as being found throughout the World Trade Center dust were found to be produced in large number upon ignition.
So what brought the buildings down in the World Trade Center was both nano-thermite (producing the gray dust) & a more conventional explosion (producing the white dust). The obvious follow-up question is: who put these explosives there? Nano-thermite only relatively recently became available. The paper headed by Neils Harrit report references papers written in 2000 and 2001 at Lawrence Livermore Labs describing the ready availability of such material. Where else was it readily available?
This discovery of the additional "smoking bomb" of the the real cause of the collapses of the buildings has confirmed a very dark picture of the fall of the WTC on 9/11. All of the government investigations on these facts has focused instead on the terrorists who were identified as hijacking the planes and their collaborators, when their murderous criminal actions were clearly insufficient to have brought the Towers down, and certainly did not cause the collapse of Building 7 ,,.
Fires did not cause the buildings to collapse (as NIST erroneously claimed in many documents), nor did lasers, missiles, or nuclear explosions (as others have erroneously claimed), but 2 types of non-nuclear explosions set in the Twin Towers caused their collapse. Later explosions similarly caused Building 7 to collapse in 6.3 seconds. NIST's 2008 report claiming that fires caused it (despite the nature of fires & statistical mechanics facts) has the quality of a 19th-century report on perpetual-motion machines.
I have written several books showing these explosives, which were set at the behest of local agents acting in an apparently classified environment for the Twin Towers cases, were the clear cause of the buildings collapsing (see , , and ). A full criminal investigation as to who set and who ignited these potent explosive materials is very sorely needed. We should pursue all these murderers to the "ends of the Earth", exposing them and bringing them to justice. Yet the Presidential candidates have been largely silent about this. Why, since it has been only 15 years since the worst crime of the 21st Centuey?
 Crockett Grabbe, "World Trade Center Collapse," Laissez Faire City Times, written 9/22/01
 Steven E. Jones, "Why Indeed Did the WTC Buildings Completely Collapse," Journal of 911 Studies, 3, September (2006). Linked out of http://www.Journalof911Studies.com . [Earlier version in Griffin & Scott (eds.), 9/11 and the American Empire: Intellectuals Speak Out (Interlink Publishing, Northhampton, MA, 2006].
 Steven Jones, Jeffrey Farrer, Gregory Jenkins, Frank Legge, James Gourly, Kevin Ryan, Daniel Farmsworth, and Crockett Grabbe, "Extremely High Temperatures during the World Trade Center Destruction," Journal of 911 Studies, 19, January, (2008) online at http://www.journalof911studies.com/articles/WTCHighTemp2.pdf
 Kevin R. Ryan, "The Top Ten Connections between NIST and Nano-thermite," The Journal of 911 Studies 22, July, 2008. Linked out of: http://www.Journalof911Studies.com .
 Niels H. Harrit, Jeffrey Farrer, Steven E. Jones, Kevin R. Ryan, Frank M. Legge, Daniel Farnsworth, Gregg Roberts, James R. Gourley and Bradley R. Larsen, "Active Thermitic Material Discovered in Dust from the 9/11 World Trade Center Catastrophe," The Open Chemical Physics Journal, 2, 7-31 (2009). Online at: http://www.bollyn.com/public/Active_Thermite_at_WTC.pdf
 Jim Hoffman, "Explosives Found in World Trade Center Dust," online at http://www.911research.wtc7.net/essays/thermite/explosive_residues.html
 NIST Investigation Committee, "Final Report on the Collapse of the World Trade Center Towers," 2005.
 NIST Investigation Committee, "Final Report on the Collapse of Building 7 of the World Trade Center," 2008.
 David Ray Griffin, "The Mysterious Collapse of WTC 7: Why NIST's Final 9/11 Report is Unscientific and False," 3/3/2011, online at: http://mycatbirdseat.com/2011/03/david-ray-griffin-the-mysterious-collapse-of- WTC-7/ .
 Crockett Grabbe National Swindle of the WTC (Amazon.com, 2013)
 Crockett Grabbe, Anatomy of Mass Murders (Amazon.com, 2013, new edition being writen for 2016)
 Crockett Grabbe, How the WTC Was REALLY Demolished on 9/11: Image-rich Analysis (Amazon.com, 2015)