John McCain has a 'very personal' reason for opposing the use of torture.
I'll use a simple definition of torture: any physical or mental coercion
that applies lengthy intolerable stress on body and or mind.
"Water boarding" qualifies.
Why would Senator McCain oppose torture, including 'waterboarding',
if he were President?
ANSWER: Because he himself was TORTURED REPEATEDLY
by the North Vietnamese when he was a POW held in the infamous
'Hanoi Hilton'.
To me, that makes him an expert on torture.
And if he says that torture, or any similar interogation techniques
DON'T WORK, then you best listen to him, considering his personal experience.