In the end it doesn't matter because it is far too late to change anything now.
They pulled 9/11 off then used it to get Americans fired up to go to war.
It worked out perfect, they went to the middle east, killed a million Arabs and accomplished their goals.
Even the coach of the Super Bowl Champion Seattle Seahawks tried to do something about it.
http://www.veteranstoday.com/2014/01/23/911superbowl/
I think its a lot easier to believe 911 was a result of an intelligence failure born out of incompetence and bureaucracy then a planned op by our govt. I do think they profited off of it like they always do, but even in regards to Iraq, the Al-Qaeda connection was basically an afterthought after the other "evidence" wasn't convincing enough. Also later reports revealed that there was a ton of pushback from the intelligence community on the administration's Bin Laden/Iraq claims. Seems like if 9/11 was part of some conspiracy they would have covered their tracks a little better.
In general I feel like the 9/11 truther theories detract from the military/industrial/complex issue by putting a "crazy" spin on the conversation, makes it easier to dismiss. The facts that we can confirm are f*cked up enough without falling into the rabbit hole of some of these conspiracies. I'm supposed to take Pete Carroll serious about something other than football?