On the afternoon of September 11, 2001, President Bush spoke from Offutt Air Force Base in Nebraska with his advisers in Washington, D.C. via videoconference. CIA Director George “Tenet told him it did indeed look as if al-Qaeda were responsible [for the terrorist attacks]. A check of the manifests of the four hijacked planes had found three passengers who were known members, and electronic surveillance had picked up congratulatory communications among al-Qaeda figures.”
– Peter Baker, Days of Fire, Page 130