EVEN THOUGH WE HAVE ALREADY PASSED THE TENTH anniversary of the 9/11 attacks, a group of 9/11 conspiracists are working hard to claim scientific validity for their conjecture that the World Trade Center buildings were destroyed through controlled demolition. The architect Richard Gage is the founder of the nonprofit organization Architects and Engineers for 9/11 Truth, which focuses on the controlled demolition theory. So outraged was I by the George W. Bush administration's justification for the war in Iraq based on faulty WMD intelligence information that I initially thought that Gage might be on to something. Then I examined his science carefully and engaged him in a spirited debate on March 6, 2011 in front of 250 people in Boulder, Colorado. (1) The video of that debate is not being released (his own website admitted that twice as many people changed their minds in my direction as his during the debate), so I created 20 short videos on YouTube [chrismohr911] that present detailed rebuttals of each of Gage's claims. What follows is a brief summary of his points and my rebuttals to them.

1. Explosive devices were carefully and secretly planted in the WTC buildings. You cannot secretly prepare a controlled demolition of the two World Trade Center buildings containing 50,000 workers, plus extensive security systems and guards, working round the clock, without anyone noticing anything unusual. Instead, we should accept at face value what we all witnessed: two massive jets that slammed into the buildings, damaging the structures and setting off raging fires and igniting more than 40,000 square feet of office space per floor in a matter of seconds, including furniture, carpeting, desks, paper, etc. You cannot control the area around such a raging fire to to have the proper conditions to start a demolition. (2)

2. No tall steel frame building ever collapsed before 9/11 due to fire.

Though it is true that no tall steel frame buildings ever collapsed due to fire alone prior to 9/11, since then, other tall steel framed building has. On May 13, 2008, a large part of the tall concrete-reinforced steel architecture tower at the Delft University of Technology in the Netherlands caught fire and thereafter had a very fast, nearly straight-down collapse mostly into its own footprint. Gravity increases the force of a falling object by a factor of 3[degrees] for a single collapsing floor, and collapsing buildings have nowhere to go but straight down. Other types of steel frame structures have also collapsed due to fire. (3)

3. What about the almost free fall collapse of the Twin Towers? The key is the "almost" modifier. If I told you I was making almost $100,000 per year and you found out I was making only $67,000, you'd say I was exaggerating. So stop exaggerating the collapse speed of the WTC Towers! The 80,000 tons of structural steel slowed down the collapse of each of the Twin Towers to about 2/3 of free fall. (4) And the cores collapsed at about 40% of free...