Obviously, to defeat our enemies we need intelligence, but intelligence that is reliable. We should not torture or treat inhumanely terrorists we have captured. The abuse of prisoners harms, not helps, our war effort. In my experience, abuse of prisoners often produces bad intelligence because under torture a person will say anything he thinks his captors want to hear—whether it is true or false—if he believes it will relieve his suffering. I was once physically coerced to provide my enemies with the names of the members of my flight squadron, information that had little if any value to my enemies as actionable intelligence. But I did not refuse, or repeat my insistence that I was required under the Geneva Conventions to provide my captors only with my name, rank and serial number. Instead, I gave them the names of the Green Bay Packers’ offensive line, knowing that providing them false information was sufficient to suspend the abuse. It seems probable to me that the terrorists we interrogate under less than humane standards of treatment are also likely to resort to deceptive answers that are perhaps less provably false than that which I once offered.
— John McCain via Reddit.