A newly declassified report slams senior CIA officials for not taking threats seriously, not cooperating, and not following up on sensitive information indicating an al-qaida terrorist threat. This information confirms my own strong belief that the September 11, 2001 attacks could have been prevented by American intelligence agencies. I remembering being stunned to learn that President Bush and other top US officials received strong warnings in the summer of 2001. Former vice president Al Gore, in a October 2004 speech, also included a strong critique of the handling of pre-9/11 warnings.
Link
Update - March 2024: There were also intelligence warnings given to the US Government from several leading international intelligence agencies prior to the 9/11 terror attack....I remember reading online years ago a website page with a list of such warnings from international intelligence agencies of an impending terror attack being plotted by terrorists, but I can no longer find that website page or link, here are 3 active links of now of this information. As a college student, such information was of interest to me and now I feel it is an academic question and public policy question of historical interest.
https://en.wikipedia.org/wiki/September_11_intelligence_before_the_attacks
https://www.csmonitor.com/2002/0523/p11s01-coop.html
https://www.americanprogress.org/article/think-again-remember-bushs-vacation/
