From Paul Craig Roberts, Former Assistant Secretary of the Treasury in the Reagan administration and former editor of the Wall Street Journal. (Hardly left-wing credentials!)
"...Scientists and engineers, such as Clemson University Professor of Engineering Dr. Judy Woods and BYU Professor of Physics Dr. Steven Jones, have raised compelling questions about the official account of the collapse of the three WTC buildings. The basic problem for the government's account is that the buildings are known to have fallen at free fall speed, a fact that is inconsistent with the government's "pancaking" theory in which debris from above collapsed the floors below. If the buildings actually "pancaked," then each floor below would have offered resistance to the floors above, and the elapsed time would have been much longer. These experts have also calculated that the buildings did not have sufficient gravitational energy to accommodate the government's theory of the collapse. It is certainly a known and non-controversial fact among physicists and engineers that the only way buildings can collapse at free fall speed into their own footprints is by engineered demolition. Explosives are used to remove the support of floors below before the debris from above arrives. Otherwise, resistance is encountered and the time required for fall increases. Engineered demolition also explains the symmetrical collapse of the buildings into their own foot prints. As it is otherwise improbable for every point in floors below to weaken uniformly, "pancaking" would result in asymmetrical collapse as some elements of the floor would give sooner than others.
Scientific evidence is a tough thing for the American public to handle, and the government knows it. The government can rely on people dismissing things that they cannot understand as "conspiracy theory." But if you are inclined to try to make up your own mind, you can find Dr. Jones' and Dr. Woods’ papers, which have been formally presented to their peers at scientific meetings, on line at http://www.st911.org/
Experts have also pointed out that the buildings' massive steel skeletons comprised a massive heat sink that wicked away the heat from the limited, short-lived fires, thus preventing a heat buildup. Experts also point out that the short-lived, scattered, low-intensity fires could barely reach half the melting point of steel even if they burned all day instead of merely an hour.
Don't ask me to tell you what happened on 9/11. All I know is that the official account of the buildings' collapse is improbable."
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