I've decided to list a few composite objections here, and answer them one at a time:
Objection #1: The Catechism of the Catholic Church says that torture is intrinsically evil if done to "extract confessions, punish the guilty, frighten opponents, or satisfy hatred..." but it doesn't say anything about torture being intrinsically evil if it's being done for the purpose of gathering intelligence. Therefore, we can conclude that it's fine to torture somebody for intelligence-gathering purposes.
Answer #1: The phrase "extract confessions" does not mean what it might seem at first glance to mean in English. The Latin words are " ad confessiones extorquendas," and while my Latin scholarship is not necessarily of the best, I recognize in the word "confessiones" the root verb "confiteor," which means "to confess , admit, acknowledge; to reveal (one's deeds, thoughts, or actions)." There is no automatic understanding in the Latin that we're talking about a "confession" as in a legally admissible statement of one's guilt designed to facilitate prosecution of one's crimes; it simply means "getting someone to admit to or reveal their deeds or thoughts or actions," and there's no limitation implied as to the purpose to which that information will be put.
So in the Latin the phrase"extract confessions" simply means to use force or threats to make someone tell you something they know--in other words, to obtain information from them by force. And the use of torture to extract this kind of confession is clearly forbidden by the Catechism.
Now, I realize that some may object that given my admitted Latin weakness I might be getting this wrong. But it agrees with what Pope Benedict XVI said when he said, "I reiterate that the prohibition against torture cannot be contravened under any circumstances." And it also agrees with what Cardinal Martino said back in 2005:
At a news conference about the peace message, Cardinal Renato Martino, head of the Vatican's pontifical council on peace and justice, was asked if torture could be a legitimate tool to gain information that might prevent terror attacks.
The prelate replied that there was no justification for using torture, which is the "humiliation of the human person, whoever he is."
"The church does not allow torture as a means to extract the truth," Martino said. Terror suspects "sometimes say what the torturers want to hear. ... There are other ways to obtain the truth."
Objection #2: Yes, torture is evil. But this particular method of enhanced interrogation (waterboarding, cold cells, sleep deprivation etc.) is not torture, because there's no blood, there's not usually any permanent damage, and nobody ends up missing an arm or leg. So unless you think terrorists should get the comfy chair and a nice salad bar, you're silly to say that these things are torture.
I think there is a misunderstanding here, an equation of the word "torture" with the words "savage brutality." I don't think that you have to be brutal beyond a certain degree to be inflicting torture; you just have to intend to hurt somebody, and to hurt him enough to force him to do whatever you want him to.
Suppose you make a video showing a group of soldiers gang-raping the terror suspect's six-year-old daughter. The terrorist doesn't know that the video has been faked, and that nothing has happened to his daughter; he believes that she has been violated in this terrible way. Is it torture to put this video on a continuous loop and play it in his cell 24 hours a day, after telling him that the soldiers are going to do the same thing again tomorrow, and the day after that, and so on until he cooperates or she dies? You're not hurting him physically at all. There's no blood. He's not in pain--not physically, anyway. His child hasn't really been brutalized in the way the video shows, and the screams she appears to be screaming are just sound-effects. So it's not torture, right?
Anyone who thinks that this scenario doesn't describe torture isn't somebody I'd want around my own children. Such a thing could easily drive a man past the bounds of sanity, especially if he doesn't actually have the information his captors are demanding from him.
Torture is a matter of intent, and when the intent is to hurt someone either physically or psychologically as a way of forcing his cooperation in some manner then it doesn't matter if the act of torture is permanently scarring or just a really, really ugly thing to do to a fellow human being. Like my scenario, or drowning a man repeatedly, or putting him nearly naked into a prison cell that is 42 degrees Fahrenheit, or keeping him awake to the point where he begins to hallucinate and begins suffering serious mental symptoms.
Objection #3: Torture for sport or done by evil dictators is bad, sure. But we're the good guys. If we have to use these techniques it's because of our love for our fellow man. We're trying to protect the innocent. Torture, therefore, is legitimate self-defense, when we use it.
Answer #3: I was going to do a whole post on this one. The error here is the idea that there is such a thing as preemptive self-defense; not too hard a notion to accept if you also believe in preemptive war, but wrong nonetheless (as preemptive war is).
If I live in a neighborhood that's a bit on the iffy side, and one set of neighbors seems threatening and are probably criminals, do I have the right to defend myself preemptively by lighting up their house with a rocket-launcher, preferably when they're all home? Of course not; that would be murder, even if they had actually threatened me in some way. There are things I can do to avoid danger, such as calling the police to report the threat, buying a large dog or a shotgun, or even moving to a different neighborhood--but I can't "defend" myself by killing these guys, even if I'm morally certain they deserve it and will probably hurt me sooner or later.
And if "our guys" capture somebody they're morally certain is a terrorist, and they think that maybe he's got information about future terror plots that may or may not ever come to pass, does the right to self-defense mean they can waterboard him preemptively to force him to tell what he knows before anything comes of it?
No. They can't know with certainty that the person does know anything. They can't prove that torturing him is going to save a single innocent life. But even if it could--we cannot do evil to gain good. We can't commit a murder to save a single innocent life; no Catholic approves of the murders of abortionists, however much we hate their foul work. We can't commit a rape or other sexual sin to save a life, either. And we can't torture, not even if we believe that doing so will save an innocent life.
Is this a hard thing to accept? Yes, it is. We want to defend the innocent and punish the guilty, and those desires are not bad; they are good. But if we must do evil in order to accomplish either of these goals, then we should beware.
In much of the debate about torture, it seems that we arrive back at this same place: torture isn't evil when we do it, because we want to defend the innocent. Or, in other words, the ends justify the means. But that's a very, very bad principle on which to base one's notions of morality.