Here's a former FBI interrogator — who interrogated Al Quaeda suspects — saying categorically that torture does not help collect intelligence, but that it does sell impressionable people on the legitimacy of jihad, on the grounds that a regime that tortures deserves to be attacked.
Former FBI Interrogator Jack Cloonan explains that regular interrogation tactics work well on even the worst terrorists, that there's no such thing as a "ticking timebomb" scenario, and that waterboarding has done much more harm than good. You can also see interviews with Jack Cloonan in the Oscar award-winning documentary, "Taxi to the Darkside."
(via Jon Taplin)
Update: From the comments, TCD004 sez,"Thanks for the link to our video. There's also a second video available of Cloonan where he describes some of his specific techniques he used for getting people to talk. Cloonan describes the FBI's approach as "rapport"-building, so agents often find themselves befriending and helping the terror suspects. Don't miss his story about teaching a terrorist how to swim.
You can see the rest of the Cloonan interview here."