The prisoner had decided to tell his inquisitors anything (untruthful) to get the torture to stop. "They raise cows and chickens," he told his interrogator.

Iraq's Abu Ghraib prison?

No, a prisoner of war camp in North Vietnam.

It was during the Vietnam War. The North Vietnamese interrogator wanted to know from the downed Navy pilot how the American aircraft carriers were able to stay at sea for six months at a time and feed a crew of 6,000.

The pilot, having experienced long bouts of excruciating torture at the hands of his communist captors, gave them a ridiculous answer--sating the sadistic interrogator enough to end this round of brutality.

With limited English-language skills and even less knowledge of American society, the Vietnamese officer had no idea the mammoth ships might actually hold large refrigeration units, or that resupply ships kept carriers stocked and hungry sailors fed without making a port call for months at a time.

No telling how much time and energy North Vietnamese intelligence wasted in analyzing the pilot's bogus answer. Meanwhile, our American hero survived another day.

The lesson of this story: Torture or other extreme measures in interrogation may actually be counterproductive to getting the information battlefield commanders really need.

There are legal, moral and effective ways to extract useful intelligence from an enemy prisoner of war that fall well short of the regrettable efforts at humiliation employed by a few Americans at Abu Ghraib prison.

Interrogation is the art--and science--of questioning an individual to collect, in a lawful manner and as quickly as possible, the maximum volume of usable, reliable information in support of military operations. The sources of intelligence may include insurgents, enemy prisoners of war, defectors or even intelligence agents.

A game of wits

Interrogation is tough work.

A game of wits between the interrogator and the detainee, it often involves difficult foreign languages and always-challenging cross-cultural communication. In a combat situation like Iraq, American lives are on the line every day, and there is pressure to produce actionable information about the foreign fighters, Al Qaeda operatives and Iraqi insurgents before they kill again.

A single nugget of brilliant intelligence arising from interrogation could lead to the arrest of a terrorist or pre-empt an insurgent's attack, saving the lives of civilians and the interrogator's comrades. During an open conflict, the stakes are high in every interrogation session.

Interrogators come from the military intelligence field, predominantly from the U.S. Army because they are the ones most likely to have contact with captured combatants. Paramilitary CIA officers may also become involved in interrogation.

Military police are not interrogators but often come in contact with POWs because they are responsible for guarding detainees. The MPs can assist the interrogator by observing prisoners during captivity and providing information about the detainee's habits and attitudes to the interrogators.

MPs are not supposed to be used to "soften" prisoners before interrogation.

An interrogation is not a freewheeling, no-holds-barred exercise. There are rules bound up in domestic and international law and custom, most notably the American armed forces' Uniform Code of Military Justice and the Geneva Conventions.

Force, torture, threats or inhumane treatment are prohibited. To this end, all members of the American military learn the tenets of the Geneva Conventions.

Contrary to popular belief, experience shows that force is not necessary to get detainees to cooperate. In fact, force can produce information of questionable quality. It encourages the detainee to say whatever he or she thinks the interrogator wants to hear and undermines the prospects of success of subsequent collection efforts because of injury and severe resentment.

Even the threat of violence can be counterproductive, because the inability to carry out a threat ultimately diminishes the interrogator's effectiveness should the detainee challenge the threat. Moreover, one has to wonder how effective the threat of force would be on a militant Islamic fundamentalist clearly willing to die and receive eternal salvation in the cause of jihad.

But all is not lost

The interrogator can use non-violent, psychological manipulation to collect important tactical military information. Most people can recognize these mind games from experiences in their private lives.

• Incentivized cooperation. Detention is no picnic regardless of circumstances. Rewards in exchange for information can meet a source's needs. A cup of hot tea, a cigarette, an additional blanket or some extra chow can go a long way toward establishing rapport with a prisoner and getting him or her to talk about topics of interest. The detainee also realizes that further cooperation with interrogators can bring additional short- and long-term benefits.
  
• Good cop/bad cop. Right out of a TV show, a first interrogator may raise his voice, wave his arms or throw a chair across the room in the presence of a detainee to get him or her to talk. The first interrogator is then relieved by a second who tells the prisoner that the first interrogator is a "jerk" and prone to violence. The second interrogator then uses their perceived mutual dislike of the blustering interrogator to establish a rapport and get the detainee to talk, perhaps out of an implied fear that the first interrogator will return if the prisoner doesn't cooperate with the second.
  
• Pushing emotional buttons. We are all motivated by something--hatred, envy, fear, love or even ideology. These emotions can be played upon to garner information. For instance, some enlisted troops hate their officers for a whole host of reasons. The interrogator could, falsely or not, commiserate with an enlisted detainee about how they both hate their superior officers, thereby developing a bond from which communication and trust can flow, hopefully leading to useful, actionable intelligence.
  
• Pumping up the ego. Who doesn't love to be flattered, especially if you are a low- to mid-level member of an organization? A little flattery from an interrogator might be just the thing to seduce a detainee into "proving" that he is the real brains of his insurgent outfit and spilling his guts about how his group is structured and operates.

Not immoral or illegal

These techniques--among others--are manipulative, but they aren't immoral or illegal--especially when lives are on the line in a conflict. It takes real leadership and professionalism to keep oneself from going over to the dark side of humiliating and torturing detainees.

Unfortunately, it appears that some U.S. soldiers and contractors crossed that line in Iraq.

Their behavior is inexcusable. Most likely, it also ran at cross-purposes to our intelligence collection efforts, not to mention our efforts to win the hearts and minds of the Iraqi people.

President Bush and Defense Secretary Donald Rumsfeld did the right thing by condemning this behavior as technically and politically unproductive and counter to the values of the American people and armed forces. There are other, far more effective ways to achieve the interrogator's goals.

Peter Brookes is a senior fellow for national security affairs at the Heritage Foundation and a veteran of the CIA and Naval Intelligence.