From 1993 to 1996, Michael Scheuer, a 22-year veteran of the CIA, headed a special unit the agency set up to track Osama bin Laden. Scheuer, who retired from the CIA in November 2004, has authored two books under the pen name Anonymous: Imperial Hubris: Why the West Is Losing the War on Terror; and Through Our Enemies' Eyes: Osama bin Laden, Radical Islam, and the Future of America. He tells FRONTLINE that he was not surprised that the investigation of the Sept. 11 attacks led to Europe. "We had a very difficult time, as one intelligence agency to another, convincing the Europeans that bin Laden and Al Qaeda were really a threat," he says. Scheuer also discusses the policy of rendition, whereby the clandestine services capture suspects and send them to third countries, a policy that he says was "cobbled together" by the CIA. "The back end has never been discussed, has never been settled," he says. "How do we handle the people we capture? The only answer we came up with -- and it's the agency that came up with it and it was blessed by lawyers -- was to take these people to countries that wanted them for their crimes of terrorism."