<human>: Can you condense the text into a few key points?

My friend recently watched Zeitgeist, a documentary about 9/11 being orchestrated by the government (among other things). While it's probably the best that I have ever seen the theory be laid out, I still don't buy any of it. My friend on the other hand, had his universe shattered and went on to watch/read more about the theory. Now he's completely convinced that  9/11 was an inside job. This conspiracy really bothers me for personal reasons and I'm looking to get as many facts as I can to refute his claims when I confront him. He keeps bringing up the lack of fuselage debris and the Pentagon in particular.
<bot>: My friend is now a 9/11 conspiracy theorist and I'd like to try to change his opinion with all of the facts I can get.