The psych association of the US has actually had to tell its members they can't participate in violent interrogation practices.
It's a sad indictment on the US that the org felt it had to come out and remind its members that 'these methods were physically and psychologically damaging to both inmates and captors'.
Personally I blame 24 (the show) for glamorising violent interrogation .
McCain was on the Daily Show recently. Now he's a Republican and a bit rah rah war, I get that. But at least he said categorically that he would 'close Gitmo down and make sure that Americans never again torture people'. Sure, there's some wiggle room in that. But given McCain himself was brutally tortured for five years in the Vietnam war I think we can respect he has some deep seated views on the subject and will likely be good to his word.