An interesting opinion on torture came from Slavoj Zizek. He was commenting on a movie called "Zero Dark Thirty" which brought torture to a Hollywood audience.

https://www.youtube.com/watch?v=B57bdjIxfQ0

His point was that torture should be so abhorrent, that it should be in the same category as rape. Even by discussing it and debating the benefits or downside of it, we've lost quite a bit of ground in a civilized society.

For example nobody debates or discusses the trade-off of rape. It is obvious anyone who advocates for it is mentally ill, or vile and is shunned by others.

But merits of torture now are open for debate. Maybe it does find terrorist, maybe it works, or, like in this movie "Oh but see, it affects the torturers just as much, so they are suffering too, they feel guilty too, don't blame them too much ..." and so on.

Now clearly we've lost that battle because we've already engaged in it.