Setting aside the reality that permanent mental or psychological damage may occur even with these forms of coercive tactics, I think it's important that we Catholics repudiate firmly and unequivocally the idea that torture is only torture if it causes significant and/or permanent injury to the person being tortured. It is possible to cause severe, even excruciating pain, both mental and physical, without leaving any marks, let alone any permanent injury; and the Catechism of the Catholic Church says the following:
2297 Kidnapping and hostage taking bring on a reign of terror; by means of threats they subject their victims to intolerable pressures. They are morally wrong. Terrorism threatens, wounds, and kills indiscriminately; it is gravely against justice and charity. Torture which uses physical or moral violence to extract confessions, punish the guilty, frighten opponents, or satisfy hatred is contrary to respect for the person and for human dignity. Except when performed for strictly therapeutic medical reasons, directly intended amputations, mutilations, and sterilizations performed on innocent persons are against the moral law.91So, what is waterboarding? It is an act of physical violence. The person being waterboarded is strapped to a board without his consent; he is helpless, and can't move. Often plastic is put over his face to increase the sensations that he is drowning and can't breathe. Water is then poured into his nose and mouth; his body reacts to this as if he really were drowning, even if in his mind he realizes that this is not the case--but few people are capable of remaining mentally calm when their bodies are straining at bonds trying to escape death by drowning. This physical reaction can, indeed, cause extreme pain, unconsciousness, and suffocation; it is possible to kill someone using this technique.
The intent of doing this is clearly to cause pain and terror. It is done to force someone's cooperation, to coerce their will, and to frighten them into compliance with the torturers' demands. It is not a legitimate act of restraint or punishment, such as might be said of incarceration and its trappings (e.g. bland food, tiny accommodations, boredom, restriction of movement, etc.). It is done wholly to cause suffering on the grounds that this suffering will then lead to the "good" results the torturer desires.
Waterboarding, like deliberate and extended sleep deprivation done for its own sake (as opposed to the sleep deprivation which can sometimes occur in a prison setting when unruly or noisy prisoners keep others from their rest) and cold cells in which the temperature is significantly reduced in order to cause the pains of hypothermia, treats the prisoner as an object. His human dignity is stripped from him because he is seen to be possessed of some useful information; whether that is true or not does not matter to those who are certain that he will be useful if he can only be broken. He may be guilty of acts of terror and deserve a trial and some just punishment, but the decision to torture him is made whether his guilt can be or has been proven; there is no such thing as "innocent until proven guilty or until we decide to waterboard you," and so torture is an offense against justice as well as against mercy.
I have heard some argue that since we train our military to withstand waterboarding, waterboarding must not be torture. However, this is a misunderstanding which fails to give the proper credit to the notion of free will and of trust; the military member understands that he has consented to the training by the fact of his military position, and he also trusts those training him not to injure or kill him in the course of the training. No such free will or trust is possible to the person being tortured, as he does not consent to the waterboard, cannot escape it, may even break his limbs trying desperately to get away from his restraints, and cannot trust the people pouring the water in his nose and mouth to stop choking and drowning him if he is too close to death.
The question, "Is waterboarding torture?" must be answered, "Yes--if the intent in strapping someone to a board and pouring water over him is to make him feel as if he is drowning, to cause him pain and terror, to coerce his will for some purpose, and to do so in a context in which free will and trust are wholly absent." Catholics must reject the idea that waterboarding isn't torture just because the victim is left in one piece and is usually left alive; that's not good enough to erase the clear intent of those who employ this tactic, when their intent is to do exactly what the Catechism calls "torture."