All of the killing processes examined in this section have the same basic problem. By manipulating variables, modern armies direct the flow of violence, turning killing on and off like a faucet. But this is a delicate and dangerous process. Too much, and you end up with a My Lai, which can undermine your efforts. Too little, and your soldiers will be defeated and killed by someone who is more aggressively disposed.
An understanding of the physical distance factor, addressed in the section “Killing and Physical Distance,” combined with a study of all of the other personal-kill-enabling factors identified thus far, permits us to develop an “equation” that can represent the total resistance involved in a specific killing circumstance.
To recap, the variables represented in our equation include the Milgram factors, the Shalit factors, and the predisposition of the killer.
The Milgram Factors
Milgram’s famous studies of killing behavior in laboratory conditions (the willingness of subjects to engage in behavior that they believed was killing a fellow subject) identified three primary situational variables that influence or enable killing behavior; in this model I have called these (1) the demands of authority, (2) group absolution (remarkably similar to the concept of diffusion of responsibility), and (3) the distance from the victim. Each of these variables can be further “operationalized” as follows:

• Proximity of the obedience-demanding authority figure to the subject
• Subject’s subjective respect for the obedience-demanding authority figure
• Intensity of the obedience-demanding authority figure’s demands of killing behavior
• Legitimacy of the obedience-demanding authority figure’s authority and demands
• Subject’s identification with the group
• Proximity of the group to the subject
• Intensity of the group’s support for the kill
• Number in the immediate group
• Legitimacy of the group
• Physical distance between the killer and the victim
• Emotional distance between the killer and the victim, including:
—Social distance, which considers the impact of a lifetime of viewing a particular class as less than human in a socially stratified environment
—Cultural distance, which includes racial and ethnic differences that permit the killer to “dehumanize” the victim
—Moral distance, which takes into consideration intense belief in moral superiority and “vengeful” actions
—Mechanical distance, which includes the sterile “video game” unreality of killing through a TV screen, a thermal sight, a sniper sight, or some other kind of mechanical buffer.
The Shalit Factors
Israeli military psychology has developed a model revolving around the nature of the victim, which I have incorporated into this model. This model considers the tactical circumstances associated with:
• Relevance and effectiveness of available strategies for killing the victim
• Relevance of the victim as a threat to the killer and his tactical situation
• Payoff of the killer’s action in terms of
—Killer’s gain
—Enemy’s loss.
The Predisposition of the Killer
This area considers such factors as:
• Training/conditioning of the soldier (Marshall’s contributions to the U.S. Army’s training program increased the firing rate of the individual infantryman from 15 to 20 percent in World War II to 55 percent in Korea and nearly 90 to 95 percent in Vietnam.)
• Recent experiences of the soldier (For example, having a friend or relative killed by the enemy has been strongly linked with killing behavior on the battlefield.)
The temperament that predisposes a soldier to killing behavior is one of the most difficult areas to research. However, Swank and Marchand did propose the existence of 2 percent of combat soldiers who are predisposed to be “aggressive psychopaths” and who apparently do not experience the trauma commonly associated with killing behavior. These findings have been tentatively confirmed by other observers and by USAF figures concerning aggressive killing behavior among fighter pilots.[32]
An Application: The Road to My Lai
We can see some of these factors at work in the participation of Lieutenant Calley and his platoon in the infamous My Lai Massacre. Tim O’Brien writes that “to understand what happens to the GI among the mine fields of My Lai, you must know something about what happens in America. You must understand Fort Lewis, Washington. You must understand a thing called basic training.” O’Brien perceives both cultural distance and training/conditioning (although he does not use those terms) in the bayonet training he received when his drill sergeant bellowed in his ear, “Dinks are little s***s. If you want their guts, you gotta go low. Crouch and dig.” In the same way, Holmes concludes that “the road to My Lai was paved, first and foremost, by the dehumanization of the Vietnamese and the ‘mere gook rule’ which declared that killing a Vietnamese civilian did not really count.”
Lieutenant Calley’s platoon had received a series of casualties from enemies who were seldom seen and who seemed always to melt back into the civilian population. The day before the massacre, the popular Sergeant Cox was killed by a booby trap. (Increasing the “relevance” of their civilian victims and adding the recent experience of losing friends to the enemy, while also increasing the intensity of group support for killing.) According to one witness, Calley’s company commander, Captain Medina, stated in a briefing to his men that ‘“our job is to go in rapidly, and to neutralize everything. To kill everything.’ ‘Captain Medina? Do you mean women and children, too?’ ‘I mean everything.’” (Moderately intense demands of a legitimate and respected authority figure.)
When we look at photographs of the piles of dead women and children at My Lai it seems impossible to understand how any American could participate in such an atrocity, but it also seems impossible to believe that 65 percent of Milgram’s subjects would shock someone to death in a laboratory experiment, despite the screams and pleas of the “victim,” merely because an unknown obedience-demanding authority told them to. Although it is