Here is my issue. If you speak to many soldiers who were in a large scale conflict (Vietnam/Korea), or knew fellow service members who were in prison camps, they will almost universally say that torture is a bad thing. Not just the act of the other guy doing the torture, but our guys doing torture.
I, having never served, tend to go with those who have some measure of personal experience on the matter.
This is not to say you haven't served, and if you did, thanks, and I respect your opinion. However, when John "Drop Bombs First and Often" McCain, says that it is a horrible bad no good thing, I might tend to listen to him. This statement in no way says that I think John McCain is the penultimate source of authority on this, just that he has some very specific experience that is pretty relevant.