On August 15, 2001, “a flight school in Minnesota contacted the local FBI field office to express concern about a student, Zacarias Moussaoui. He had asked suspicious questions about the flight patterns around New York City and whether the doors of a cockpit could be opened during flight. The local bureau quickly determined that Moussaoui was an Islamic radical who had been to Pakistan and probably to Afghanistan. The agents believed he might be a potential suicide hijacker. Because he was a French citizen who had overstayed his visa, the INS [Immigration and Naturalization Services] placed him under arrest. The FBI agents investigating the case sought permission from headquarters to examine Moussaoui’s laptop, which was denied because the agents couldn’t show a probable cause for their search. When the Minneapolis supervisor pressed the matter with headquarters, he was told he was trying to get people ‘spun up.’ The supervisor defiantly responded that he was ‘trying to keep someone from taking a plane and crashing into the World Trade Center.’ ”
– Lawrence Wright, The Looming Tower, Page 396