The question of "torture" is again front and center in the ongoing debate over how to fight the war on terror. Judge Michael Mukasey, President Bush's well-qualified pick for the next attorney general, was questioned closely at his confirmation hearings last week on whether torture is illegal -- it is -- and what constitutes torture.

He rightly would not commit to answering that question, especially with respect to the controversial practice of "waterboarding" (that is, simulated drowning) without more information, and got attacked for his candor. Yet, defining torture raises complex legal, policy and moral issues, and cannot be done without taking into account all of the facts and circumstances surrounding the use of any particular interrogation technique. It is time for a national debate that involves those facts and circumstances.

The Bush administration's critics invariably portray all coercive interrogation methods, from forced standing to waterboarding, as torture. This obviously gives them an advantage in the debate, since torture is reprehensible and fundamentally inconsistent with United States policy. They also act as if the mere asking of what constitutes the permissible levels of coercion is immoral, at best, and unlawful at worst. Their arguments, however, are flawed both as a matter of law and policy.

The law defines torture as the intentional infliction of "severe pain or suffering." The intentional infliction of pain or suffering that is not severe is not torture, although depending upon the circumstances it may constitute forbidden "cruel, inhuman or degrading" (CID) treatment.

These terms, of course, are no less difficult to interpret than "severe" pain or suffering. Congress attempted to give them some meaning in the 2005 Detainee Treatment Act (DTA). This law effectively excluded the U.S. military from terrorist interrogations because it limits the Pentagon to techniques approved in the U.S. Army field manual, a highly restrictive document designed to govern the treatment of honorable prisoners of war protected by the Geneva Conventions.

However, the DTA left the CIA free to use aggressive interrogation methods on captured terrorists -- who do not enjoy Geneva protections -- so long as they are not subjected to torture or CID. Congress further defined CID by reference to the Constitution's due process and cruel or unusual punishment provisions, which in turn generally involve a "shock the conscience" standard.

The problem is obvious. Like the words cruel, inhuman and degrading, whether or not a particular interrogation method shocks the conscience depends very much on the circumstances.

For example, the harsh methods of Marine basic training, designed to break the soft habits of civilian life and inculcate a warrior spirit and iron discipline, might well be cruel or degrading if imposed on middle-aged lawyers or politicians, but not when used on 20-year old recruits. And the case law interpreting the Constitution leaves more than enough room for argument about the methods allegedly utilized by the CIA. Based on published reports, these include slapping, exposure to cold, stress positions, interrupted sleep and waterboarding, alone or in some combination. The Justice Department has reportedly approved all of these as legal.

Reasonable minds can disagree with this finding, although it is unlikely that Justice signed off on these methods without regard to the level of intensity or potential cumulative impact involved. Slapping a man's face probably does not cause him severe pain. Breaking his nose probably does.

Similarly, forcing a prisoner to maintain an uncomfortable posture for a period of time is not cruel, inhuman or degrading, although forcing him to do so while naked, shackled to the floor in near freezing temperatures might be. It is a matter of degree. The possible exception is waterboarding, which presents unique issues because its sole purpose and effect is to create a feeling of suffocation. This involves the physiological and psychological responses to drowning.

It is difficult to see how this, in and of itself, does not constitute at least severe suffering. At the same time, of course, there is no actual danger of drowning or other injury, and waterboarding has been part of U.S. military training programs on interrogation resistance. (If it is torture, then it is impermissible for all purposes -- whether or not an individual has consented.) This is, in short, a difficult and close question, and an especially wrenching one for those who actually have the responsibility to decide whether waterboarding should be used to obtain intelligence that may well save innocent lives. Mr. Mukasey was right to demur.

Regrettably, the response of administration critics to these questions has largely been one of sweeping and outraged claims of "torture" -- not a detailed and reasoned discussion of whether and why the approved methods cross the line. Their bottom line seems to be that any form of coercion is forbidden, period. That simply is not the law and, taken to its logical conclusion, this position would effectively eliminate interrogations altogether.

By their very nature, every interrogation is coercive. The fact that it is backed up by some element of force or the threat of force is what distinguishes it from a mere conversation. More generally, varying degrees of coercion are present in many public institutions, including penitentiaries, boot camps for juvenile and adult offenders, police training academies and many aspects of military life. These approaches have been debated over the years by the American polity, at both the federal and state levels, and continue to enjoy public support. All of this suggests that, at a minimum, stressful interrogations consistent with the U.S. military's basic training should be permissible as a matter of course, with other methods to be considered on a case-by-case basis.

For their part, the administration's critics should identify which, if any, interrogation methods they believe are legal and moral and explain how their view fits within the broader existing societal consensus on the permissibility of coercion in certain circumstances. Alternatively, they should clarify why an American democracy facing an implacable and ruthless foe should continue to use coercive techniques when training its own military personnel, but should treat captured (unlawful) enemy combatants with scrupulous tact and unfailing politeness.

Some, of course, have suggested that relationship-building interrogation techniques are preferable -- as more reliable in the long run -- to "stress" methods. If true, this is only a partial answer. What about the hard cases, such as 9/11 mastermind Khalid Sheik Mohammed, who may not be susceptible to relationship building?

Many, probably most, Americans will find this debate uncomfortable and embarrassing because all of the interrogation methods at issue, if not cruel or degrading, are certainly nasty and aggressive. Whether the question is holding a prisoner for hours in shackles, or subjecting him to simulated drowning, this is not the type of activity Americans like to associate with their government or themselves.

At the same time, Americans rightfully expect to be protected from attack. But there is no free lunch. Coercive interrogations have been key in preventing post-9/11 attacks on American soil. To preempt future attacks the intelligence agencies must continue to have information that can often be obtained only from captured terrorists. The intelligence agencies are the first line of defense -- but the body politic cannot expect them to "do what it takes" and then also claim the right to punish them for crossing lines that have never been properly defined. We are all in this boat together.

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