re: the 9/11/2001 Al-Qaeda attack:
Though they could not know it, time was running out. In December 2000, the CIA submitted a new plan in its targeting of al Qaeda "that would have significantly expanded our activities. ... It was too late for the departing Clinton administration to take action on this strategic proposal."
The same report speaks of excellent collaboration between the CIA and FBI on numerous terror cases, but then adds: "A major, ongoing concern is FBI's own internal dissemination system. CIA officers still often find it necessary to hand-deliver messages to the intended recipient within the FBI." And it laments "the loss of potential intelligence opportunities because of deference to law enforcement goals." In other words: at what point do you make an arrest or close down a terror conspiracy?
And in a passage with echoes today, there is a complaint about leaks compromising the Agency's ability to implement what became known as "the Plan" to get bin Laden. "Persistent publicity and leaks of information about our methods in the United States and abroad caused the terrorists to [redacted] emphasize their compartmentation."
therefore:
Notably, the Inspector General's report included a warning that the long-term discipline needed in analyzing terror groups "can be difficult to maintain in the current atmosphere, which rewards instant results." Some analysts had complained about a "constant state of crisis" that limited their ability to develop in-depth expertise. One analyst "worried that he only had time to answer the mail, and as a result he might miss warning signs of a threat."