I couldn't tell if you were making an assumption of guilt based only on the thoughts of those doing the interrogation or you assumption that it's ok to torture people regardless of innocence or guilt so long as there is suspicion.
Treating people like animals or worse than animals will certainly make them into an enemy if they aren't already.
My first time being arrested, even though I was only in a cell for about 8 hours totally changed the way I view my government and police force and to some extent my society for tolerating it.
I now consider the US to be de-facto police state. After all we are the world leader when it comes to putting people in prison with over 1% of our adult population behind bars. No society in history has imprisoned more of it's citizens than the United States. 5% of the world population is American yet 25% of all people in prison in the world are American.
Back to the point of waterboarding. I'm not going to say that torture never ever ever ever has a place, but it should be considered as an exception, not standard operating procedure. Watering down waterboarding by calling it 'Enhanced Interrogation' is wrong and leads people like Melvin to think that it's no big deal.