The Psychology of Killing

There will one day spring from the brain of science a machine or force so fearful in its potentialities, so absolutely terrifying, that even man, the fighter, who will dare torture and death in order to inflict torture and death, will be appalled, and so abandon war forever.

-Thomas A. Edison

War is a progressive concept.

Not sociologically, but in the sense that what began as an “art” has evolved through direct and indirect absorption of advances in peripheral disciplines (e.g., chemical and nuclear energy and health and medicine) into a separate “discipline” that is studied in its own right. Nonetheless, the elements of science–ballistics, ordnance engineering, propellant source , mechanical engineering, electronics and nanotechnology–focus more on the generally incremental development of weapons and support systems than on analyzing the implications for fighting formations and tactics of more effective weaponry.

(There are many who contend that success or failure in battle arguably is as much the result of one commander’s superior or inferior imagination and ability to integrate the essential elements of mission, enemy, terrain, troops available, and training in formulating and implementing a battle plan.)

Modern “conventional” war–as well as the possibility of nuclear war–complicates armed conflict because the fighting systems cannot simply be plucked off a shelf at a moment’s notice. Those who engage in or favor a “war footing” thus are forever seeking new materials, new combinations of known materials, or new variations in fabricating instruments that can kill and destroy efficiently.

Contrast the huge amount of resources devoted to modern weapons development with the historically resource-starved and thus limited (or even totally ignored) study of the psyche’s rational and emotional “switches” inhibit or propel extreme behavior in groups who are allowed or who have seized an opportunity to rampage through towns and villages in a manner comparable to the “hordes” of recorded history.

While obviously incomplete and invariably written from the perspective of the winner, oral traditions and the earliest chronicles detail numerous instances when the “hordes” of “barbarians” on far-ranging conquests engaged in the frenzied slaughter of entire populations–acts that today would be considered war crimes and crimes against humanity.

The history of warfare–at least the history of the development of the means of warfare–has been to increase the “separation distance” between the combatants more or less in the manner described below.

In pre-historic times, hunter-gatherers with longer, more muscular arms and legs or who were more agile had “natural” advantages insofar as they could catch, hold, and crush others, whether animals for food or humans. The answer to raw muscle was to combine muscle power with ordinary objects such as stones and pieces of trees that could be hurled to have the desired effect of injuring or killing.

The natural progression of applied experience also led to the realization that weaponry was indiscriminate: whenever used–whether held or hurled–injury or death ensued for whatever was struck, whether intentionally or by accident, friend or foe, human or animal. By the 4th millennium BCE, when human activity was being captured in the earliest chronicles, not only had war been “born,” it was a mature endeavor often involving hundreds if not thousands of individuals.

It invariably was most hazardous to the ground infantry that often participated against their will. Bat battles were won or lost when masses of men in tight, shoulder-to-shoulder formations crashed into one another. Whatever they were called–Greek hoplites organized into phalanxes of heavy infantry carrying the elongated spear and heavy interlocking shields or the more mobile Roman legions that relied on the short sword once inside the line of spearheads.

The first effective weapon that distanced opponents was the throwing spear or javelin. Accounts of battles sometimes hyperbolically claimed that the numbers of missiles were such that they threatened to blot out the sun. There were drawbacks, however; there was no energy “multiplier”–the spear’s flight distance depended on the muscular energy transferred from the thrower’s arm to the spear shaft; the weight of the missile (which depended on the wood selected for the shaft; and the terrain elevation of the target vis-à-vis the thrower’s, elevation. In modern times using high technology, the current men’s distance rev for throwing the javelin is 323 feet which the mark for women is 235 feet. In war, with the swirl of battle, with the objective of wounding or killing the enemy is paramount; such distances would never be reached. Moreover, the spear throwers either would have to fall back to get the next missile or go into action carrying more than one.

Bows, unlike spears, multiplied the muscular strength exerted by the archer, with the “factor” depending on the type and condition of the wood and the wood used for the arrow. The real revolution in the bow-and-arrow was the English long bow. While t the period authorities provide no uniform data, the consensus is that the bows were made from yew wood, were between five and six feet long (the continental bow measured no more than four feet, and could be fired with enough force to travel 18-240 yards and still penetrate the target. A trained archer could fire 12 to15 arrows in a minute ­leading one source to refer to the longbow as the machine gun of the Black Prince.

At the same time as the longbow came into its own on the field of battle, gunpowder was introduced into Western Europe. This was the real revolution, for this involved not just the transfer or multiplication of stored muscular energy. When ignited, the materials that constituted the gunpowder underwent a chemical transformation that unleashed energy in destructive quantities never seen before.

From this point forward, the march of war technology was toward ever more powerful but controlled chemical interactions that theoretically permitted warfare to be conducted without those firing the weapons actually seeing each other. The power of nuclear energy release for warfighting similarly was a quantum leap forward–and as fundamentally revolutionary as gunpowder was to muscle power

Many erudite observers have concluded that this separation between the attacker and the attacked has so de-personalized war that it is now easier for leaders to go to war and for those doing the fighting to kill without remorse. From 15,000 feet in the sky and five or ten miles distance, a pilot only has targets to strike. Precision guided fire-and-forget missiles used against an armored force psychologically translates into a number of tanks destroyed, not the number of people killed in the destroyed tanks.

Moreover, when the attacker employs weapons such as cluster munitions which can be detonated days or weeks or months later by unwary civilians, those killed are completely unknown to the attackers.

Perhaps high technology does depersonalize warfighting. But it is equally apparent that the human race in the 21st century has not evolved psychologically beyond our pre-historic ancestors in discerning–let alone understanding — the conditions and the “triggers” of “close-quarters” combat to the death.

In the former Yugoslavia in the 1990s, in Rwanda in 1994, in Kenya in 2008, eyewitness accounts describe a shocking, absolutely chilling blood-lust that surfaced when mobs rampaged through towns and parts of towns inhabited by “them” It seemed to take hold even when the target had been in the community for years, often having raised a family with no apparent animosity from neighbors.

Some will say that this simply proves that the way to reduce gun violence is to not let the mentally unbalanced have weapons, for it is not the weapon that kills but the people who get a gun illegally or legally when they should be denied ownership. Yes, more effort needs to go into diagnosing and treating those suffering mental stress and illness–a population that is growing in this country because of Afghanistan and Iraq–with additional constraints that would make it more difficult to obtain weapons. But we are also learning that mental disturbance can be undetected for years until something snaps. If there are fewer weapons in the community, when the “snap” occurs the victim will have fewer opportunities to obtain a firearm.

But the eyewitness accounts suggest that in two of the three situations described, much of the killing was done not with firearms but with knives and machetes. A bullet or a piece of shrapnel can kill and leave only a small amount of blood; to hack an individual to death requires getting very close and invariably splatters blood widely–which in some descriptions seems to increase the frenzy of that or a subsequent attack.

Which leaves us with two psychological states:

the coldness of a rational, calculated, uninvolved, unemotional and therefore inhuman response to killing other humans

the emotionally driven, irrational, highly unstable frenzy that, requiring discharge, attacks whatever is different (and therefore “dangerous”).

Neither is good. But how to deal with the second is becoming more and more the challenge.

Col. DAN SMITH is a retired U.S. Army colonel and a senior fellow on military affairs at the Friends Committee on National Legislation. Email at





[CDATA[ $('input[type="radio"]
[CDATA[ $('input[type="radio"]
[CDATA[ $('input[type="radio"]
[CDATA[ $('input[type="radio"]