This is a documentary produced by the History Channel of the 9/11 Commission. However, it is mostly a presentation of what the history channel thinks is important rather than the official version of what happened. They kept showing the wife of a victim who had passed away in the attack over and over. She was angry and wanted answers. However their overuse of one individual made me tire quickly of the entire program.
The conclusion of the 9/11 report is that we were not expecting planes to be used as missiles and consequently were not vigilant enough in keeping something like this from happening. Several of the hijackers were known to the CIA, but dropped off the radar shortly before the attack. Only one person was thwarted by a border agent, other than that it appears all the hijackers were able to do what they wanted in hijacking the planes. However a late flight, and passenger resistance kept one plane from reaching Washington. We pretty much were caught with our pants down. Even though memos had been passed around about a significant threat from Al Qaida, specifics were not forthcoming, and departments did not add two and two together. Part of this was a lack of communication between agencies and within agencies.
Lets pray something like this never happens again.