You're an idiot. Even if you believe 9/11 was a conspiracy, you do realize that there's dozens of different conspiracy theories out there? This guy would be called a "jew loving cuck" on /pol/ because he believes the planes brought down the towers and not bombs that were placed in there weeks before hand.
Here's what happened:
A small group of people hijacked a plane and rammed it into a building because it was really easy to do that pre 9/11. The government then used that as an excuse to go to war that they were already itching to go to. The simplest explanation is usually the truth.
About the whole flying in the US and not being shot down or stopped for hours... What were they supposed to do? Shoot down the planes with their own helpless innocent citizens? Imagine being the man who has to go home and sleep after doing that for his country, or at least think of the ********* that would have been media around the world about us doing that.
You could try to intercept or a variety of other things, and shooting it down would be preferred to what happened. Unfortunately, the US' Air Defense was down for the first, and only, time in history that particular day, for some reason. If I remember correctly. I believe they also could react if they didn't ignore the calls coming in.
Bad guy who released some helpful information, but ultimately he himself is an anarchist. He released information about America's defense protocols, and sure he did blow wide open a bunch of stuff about illegal surveillance by the government but he also gave away sensitive homeland defense information to our rivals and enemies. Want to know why he went to Russia specifically?
Not because Russia is the only place he could go without being repatriated here for a trial. No no no, there are plenty of shady places to hide. He went there because he was a spy all along and sold them a **** ton of information to sit cozy in Moscow.
The biggest 'cover-ups' and conspiracies are often right in peoples faces they just take it at face value and don't bother to look it up. Look at a lot of the major activist groups, they don't even have to cherry pick, even though that is a favorite thing for them, when they are getting studies sponsored by companies against what ever it is the activist are against, for example some of the studies originally( and often refereed to by activists) involving Chernobyl were sponsored by an oil company.
That being said the government can't cover up **** the most they can do is just deny it doesn't exist and pray to god no one finds even a glimmer of evidence, and even then there is always whistle blowers that find **** out while working for the government