Maybe the truthers can explain to me how a building can remain standing after it’s been cut in half by a jetliner. I think that is the real question here, not that the towers fell but how they stood for so long after being chopped in half.
At the risk of sounding hokey, I am going to venture it was American Exceptional-ism that kept the towers standing for so long. They were extremely well made, plain and simple.
Of course, that's why George Bush had to have them demolished with explosives :-)