Because a simple hijacking would have been OK...

Rice: Pre-Sept. 11 alert too general

WASHINGTON, May 16 — The Bush administration chose not to tell the public about a potential al-Qaida threat to hijack airliners a month before Sept. 11 because it did not want to risk shutting down civilian aviation “for very general warnings,” national security adviser Condoleezza Rice said Thursday.

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Rice repeated the administration’s insistence that the al-Qaida information referred only to a general threat from bin Laden involving jetliners. She said Bush and U.S. intelligence did not know that suicide hijackers were specifically plotting to use planes as missiles, as they did against the World Trade Center in New York and the Pentagon.