Here is a great article with a load of supporting material for breaking them in slowly. Sometimes you have to knock down the government's credibility before you can get people to see the truth. Follow the link for the entire article with links to the supporting documentation. Thanks to George Washington for another great article:

http://georgewashington.blogspot.com/2005/11/introduction-to-911-for-those-who.html

The administration's claim that terrorists crashing planes into buildings was not foreseeable is flatly disproven by the following evidence:

The North American Aerospace Defense Command (NORAD), the military air defense agency responsible for protecting the U.S. mainland, had run drills for several years of planes being used as weapons against the World Trade Center and other U.S. high-profile buildings, and "numerous types of civilian and military aircraft were used as mock hijacked aircraft". In other words, drills using REAL AIRCRAFT simulating terrorist attacks crashing jets into buildings, including the World Trade Center, were run.

Indeed, on the morning of September 11, 2001 itself, the government was running a simulation of a plane crashing into a building.

The military had also conducted drills of planes crashing into the Pentagon. For example, see this official military website showing a military drill conducted in 2000, using miniatures.

Moreover, a 1998 report forwarded from the FBI to the Federal Aviation Administration concluded that "a group of unidentified Arabs planned to fly an explosive-laden plane . . . into the World Trade Center"

The CIA Director had also warned Congress shortly before 9/11 "that there could be an attack, an imminent attack, on the United States of this nature. So this is not entirely unexpected" according to a broadcast on National Public Radio

Indeed, it was widely known within the FBI in the weeks before 9/11 that an imminent attack was planned on lower Manhattan.
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