Gov't officials may start off as good people.. but in order to be successful they have to play the game like anyone else. By the time they reach the level of Congress, I have every confidence that they're done plenty of underhanded things to get there.. not the least of which is the digging up of dirt and trashing their opponents. The Govenor of Illinois tried to SELL his state's Senate seat! And was on the Television show Apprentice AFTER he was caught, impeached and convicted of a Federal Crime!
Either way.. IF the Gov't were to construct something like 9/11.. they really wouldn't need all that many people to pull it off. They would compartmentalize to a certain extent and use their lesser known tools to achieve their goals. They wouldn't have had to work with the hijackers in any capacity either. There are a lot of ways that are perfectly feasible for these things to be accomplished. I'm not saying that that's what happened. Just that it can't just be brushed off.
The Media is definitely being controlled. Without a doubt. Not necessarily by the Gov't.. but by it's owners. If Rupert Murdoch invested in a company that specialized in Personal Oxygen Tanks, you can bet your ass that soon afterwards Fox News would be airing a story on the toxicity in the air.
Personally.. I'm of the belief that the US knew about it well ahead of time and allowed it to happen. They may or may not have helped certain aspects along the way. Otherwise, how can they possibly explain having all that information about each Hijacker and their trail less than 24 hours after the fact? Remember this is the same country that struggled finding the Unabomber for 2 decades and he's one of our own citizens (in the end, his family turned him in.. the Gov't had no part in finding him)! They had either constructed the various histories or they had to have been following them the whole time.