We know that the White House had plenty of warnings about potential Al Qai'da attacks against the US. To quote the Observer :"The administration had plenty of advice about Al-Qaeda. In January 2001, the outgoing National Security Advisor, Sandy Berger, personally briefs Condeleeza Rice, his replacement, on a plan to stop Al Qaeda. Rice merely starts a slow process of policy review. Meanwhile various parts of the intelligence community are pushing the ideas of attacks with aircraft and terrorists engaging in flight training in the US. These include the plan foiled by the French to fly a hijacked jet into the Eiffel Tower and the plot in the Philippines to hijack 11 passenger planes simultaneously over the Pacific as well as the now famous 'Phoenix memo' from an FBI agent warning of terrorist flight training. In response to these pushes, there is no equivalent 'pull' from the top of the administration looking for and drawing in this intelligence. The US Congress decided last week to appoint an independent commission looking into failures leading up to 9/11."
Moreover we now know that the Bush on Aug. 6 2001 received a memo called 'Bin Laden determined to strike in the US'. Condaleeza Rice, the National Security Adviser, publically stated that during the summer of 2001 the Bush Administration believed the " al Qaeda might hijack an aircraft and use it to bargain for the release of prisoner- I don't think anyone could have predicted that these people would take an airplane and slam it into the World Trade Center" ( Financial Times 5/18-19 2002, p.6 ). This statement is cleary a lie, especially in the light of the failed Al Qai'da plan to fly a hijacked yet into the Eiffel Tower. Rice also claimed that "We only expected a traditional hijacking." The Bush Administration ignored warnings from at least France and Israel (and possibly Egypt and England) that a terrorist action was imminent; it ignored warnings from FBI agents in Arizona and Minnesota of possible airplane hijackings by terrorists training as airline pilots, and it ignored the CIA briefing to President Bush on August 6, 2001 (the 'Bin Laden determined to strike in the US' memo) stating that al Qaeda was planning a strike against the US.
I think the American people deserves to know exactly what was going on. Did the Bush administration actually expect Al Qai'da to hijack airplanes and did not warn the public? To hide behind "security reasons" as a means to cover up the facts is even more dangerous to the American people than the protection of a tiny bit (relatively speaking) of classified information.