Too many people have a vested interest in the truth NOT BEING KNOWN about how our government failed us by making 9/11 possible with a "do not see, do not listen" policy.
Consider, too, that the FBI was notified in April, 2001, by the Czechs that someone had met with Iraqi security agent al-Ani. The FBI sent two Czech-speaking agents to Prague to investigate, according to an official in the Czech government. After 9/11, the Czechs notified Washington that, hey, that guy al-Ani met with was Mohammed Atta. The FBI started throwing water on that story. Were they afraid of it being claimed that they had information that could have nailed Atta? Who knows?