The question “why war?” has long inspired scholars to seek answers in human nature. Their findings invariably have been ambiguous and judgments inconclusive. While it is easy to make the case that humans do engage in violent behavior as part of their nature, there is no basis for arguing that they are “killers.” There is no propensity to kill fellow humans that prevails over other forms of social inter-action. Moreover, the development of organized societies as their standard habitat introduces cultural and structural elements that produce a wide range of behavioral patterns. Simply put, humans in groups are capable of conducting their collective affairs in just about any manner imaginable – as illustrated abundantly by the historical record.

The effort to make sense of the connections between human nature and the phenomenon of war is getting renewed attention thanks to the rising interest in understanding Post Traumatic Stress Disorder. That interest, in turn, reflects growing awareness that there is nothing new about PTSD except that now we are chary about accepting cavalier explanations ascribing it to character flaws or the contradictions of socio-cultural conditioning.

One place to begin an exercise intended to unravel the puzzle is recognition that individual violence and war are not the same thing. All of God’s creatures engage in violence; only homo-sapiens war with each other. Our ability to do so derives from the enlarged capacity of our brains that enables us to abstract, to conceptualize, to use language and thereby, to organize joint enterprises sustained over time – e.g. war as a sociological phenomenon. Those activities engage the frontal lobes of the cerebral cortex.

That is why homo sapiens are the only species that fights wars.[1] Other mammals, even primates, don’t have the mental ability to give meaning to others and events or to set objectives beyond immediate ones – two preconditions for war. Their violent encounters have two distinguishing characteristics: a) all are brief, b) and all are keyed to matters of survival. They fight for food, for mates, and for territory which is tied to the first two.

Essentially, it is only the Reptilian brain (or R-complex brain) that is involved in those fights with a small contribution from the next evolutionary level of mental function that allows for a measure of memory, cunning and coordinated hunting – the limbic system. Hence, the susceptibility to mental impairment doesn’t exist, and the limited duration of the violence doesn’t generate the stress that creates it. Hence there is not even a counterpart to the Saturday night bar brawl among other mammals.

By contrast, there is a discrepancy between the evolved brain capabilities that make war possible, on the one hand, and our core physiology that is little different from that of other mammals, on the other. In other words, our greatly enhanced capacity for organized violence has far surpassed the rest of our psycho-somatic apparatus. No wonder we are vulnerable to stress.

Military technology that permits fighting at a distance far from the battle-field, and from the enemy, partially avoids this contradiction generated by sustained physical combat. People who push buttons, though, encounter another contradiction. Their Reptilian brain is not engaged in combat even as their brain’s higher functions are activated in killing people. That means that the conceptual awareness which is uniquely human (and the basis of mental stress) must be handled without benefit of the hormones and other physiological responses sparked by the Reptilian brain. They are dormant because the person involved is not at grips with the tangible enemy. This helps to explain the cause of the PTSD that some of the drone operators experience when snug in a Nevada cubicle.

At the other extreme, for soldiers engaged in hand-to-hand combat, the psycho-somatic condition is comparable to that of other mammals – it is the Reptilian brain that is engaged in the fighting. That probably was the experience on Saipan and Iwo Jima in WW-II. If somebody is running at you with a bayonet, your survival instinct dictates that you fight.

In Neolithic times, and until recently among small tribal groupings in the Amazon basin and Papua New Guinea, similar such encounters characterized violence between individuals and small social clusters. Even the notable ‘warfare’ among tribes that had been a feature of life in the New Guinea Highlands was not sustained and casualties low – even though engagements and raids were quite frequent. Capture, killing and at times cannibalizing the flesh of an enemy were ritualized as part of a multifaceted cultural practice. Furthermore, there is scant evidence of conquest.

(These highly insular tribes did exchange brides on occasion – perhaps in a primitive awareness of the risks to collective well-being posed by rigid endogamy).

What of the people at the top who give the commands? One might think that they have a mental/psychological experience like that of the drone pilots in their Nevada offices, only in exaggerated form. Yet, that does not seem to be normally the case. Of course, in the olden days, war and violence were taken for granted – killing and mayhem were integral to the life of a statesman.

A few striking examples of the extreme strains felt by American Commanders-in-Chief do stand out: Abraham Lincoln and Franklin Roosevelt. Four years of war induced stress was manifest. It took a heavy toll. Just compare the photographs of Lincoln in 1860 and 1865, of FDR between 1940 and 1945. Lyndon Johnson, too, never recovered his emotional balance after the traumas of Vietnam and died a near alcoholic.

By contrast, George W. Bush and Barack Obama showed no evidence of being deeply affected by decisions and actions that caused so much carnage (including the gratuitous onslaught against the Houthis for no reason other than to tighten the brotherly bond with Mohammed bin Salman. All for next to no gain; indeed counter-productive in terms of reducing the terrorism threat). Personally, I suspect that neither man missed a meal or an episode of Sports Tonight – much less a night’s sleep – over what they had wrought.

This analysis suggests that the prime question we should ask is not “why PTSD?” but rather “how is it that most humans are able to fight in wars without cracking up?”

One answer is that the human propensity to abstract reality produces the ideologies, the religious beliefs, their symbolic representations, and thereby the objectification of the “other.” That permits communal mobilization, regimentation, and protracted war-fighting. They generate feelings able to override survival impulses – for most soldiers, for a certain period of time.

A complementary answer is that there is indeed always the lurking possibility that individual soldiers put in lethal situations will bolt. Bolt out of fear. Once under fire, the adrenaline et al kicks in, and that impulse may subside. It may also rise once again after experiencing a long string of such episodes. Or, individuals cannot handle the accumulated stress – aggravated by the strain between the survival instinct to get the Hell out of there and the combination of conditioned loyalties/duties and bonding with one’s fellow “tribesmen.” Emotional dissonance ensues. That adds to the stresses that eventually can produce PTSD.

Which emotions prevail can be affected by the type of leadership provided by officers in the thick of things. Whether through example, inspiration or imposition, an effective leader can get soldiers to take high risk actions. The methods at their disposal varies from army to army. In the citizen armies of the United States or Great Britain during WW-II, for example, there were limits on the coercive means available to officers. It has been pointed out that up to a third of American infantry soldiers may never, or rarely fired, their weapons at the enemy. That was due either to their impulse to hide in a ditch or behind a tree with their head down and/or to an aversion to killing at relatively close range a visible fellow human. That percentage probably went down around Bastogne or on Pacific Isles where the survival instinct took hold.

From this perspective it is quite astounding to contemplate the suicidal trench warfare of WW-I which went on for more than 4 years. Right to the end, men on all sides would obey an order to “go over the top” in full awareness that they would be moved down by machine guns and artillery blasts – with extremely slim expectation that anything of strategic significance would come of the effort. The English and French behaved just as obediently as did the Germans nurtured in a militarized culture. So, too, the Americans who arrived on the scene late. In fact, the US Army incurred the highest fatality rate of any national force on the Western Front. Its commander, the legendary General ‘Black Jack’ Pershing, who had made his name chasing Pancho Villa around northern Mexico, knew little of trench warfare. Perhaps that’s why they gave his name to the tank that became the mainstay of armored units in WW-II.

It often is remarked that for most of history, in most places, warriors moved in fixed step within serried ranks. That is explained, in military terms, as creating mass for both offense and defense. It also makes discipline much easier to maintain. The instrument for doing so was the threat of being killed by one’s officers (immediately or afterwards) for breaking ranks.

That practice continued right into the 20th century, e.g. the Bolshevik commissars who patrolled behind the front lines shooting deserters or shirkers without inhibition. Surely, the ideal formation on strictly tactical military grounds was not to march across fields in brightly colored uniforms to be picked off by the enemy or shattered by cannon – as was the standard practice in the seventeenth, eighteenth and nineteenth centuries. 

(The military concept of mass made sense before the arrival of gunpowder and rifles – for Greek phalanxes, the Roman testudo/centurie - even the ‘British square’ when facing primitively armed foes in colonial wars). *

One wonders why nobody, in Europe anyway, didn’t break the mold in order to gain an advantage – especially against a superior force. In other words, some form of what we call guerrilla warfare today. The Spanish rebellion against the occupying Napoleonic army featured some of those unconventional elements, but that was very much an exception. The standard answer of military historians is that with a lack of tight organization, many soldiers would run away. Maybe control by aristocratic officers of dumb peasant recruits conformed to a more general social norm reinforced by the belief that the lower classes were cowardly. 

The drawback of that approach was demonstrated repeatedly over the centuries when the tightly organized armies of great states were routed by horsemen from Central Asia. This occurred time after time: the Huns, the early Magyars, the Seljuk Turks, the Mongols (mainly Turkish troops), Tamerlane, etc., etc. In fact, invading hordes of horsemen who operated with a fluidity and adaptability that gave them an enormous advantage, chalked up a streak of almost uninterrupted victories across the millennia.

The exceptions were some of their wars with Chinese dynasties which were able to prevail by drawing on vast resources to marshal formidable armies – and also to build defensive fortifications exemplified by the Great Wall. Still, even Imperial China was overrun on four separate occasions.[2] One might offer the proposition that the less structured and hierarchical the society, the less regimented was their style of fighting. Maybe the Central Asian horsemen fit that category, whereas in Europe the cavalry was normally made up of officers drawn from the upper echelon of society. (Think of those dazzling cavalryman uniforms at gala balls – handsome hussars or uhlans whose torn bodies soon would litter some blood-spattered battlefield). 

Did these fierce horsemen of the Asian steppe suffer from PTSD? Any speculation should bear in mind that they were bred in a culture where killing and risking death in battle were taken to be what life was all about. That said, there probably were a few who did experience PTSD at some point in their wild perambulations across the continent. What might their symptoms have been? How were they interpreted? Was the condition concealed? Perhaps the sufferers figured among those Mongols who settled in Afghanistan with their families in the 13th century. They are the ancestors of today’s Hazara minority. Most settlers, though, probably just wearied of the tribulations they had endured year after year.

Notes

1] There is a highly influential school of academic thought that human violence is an inborn instinct that inexorably produces violent behavior – individual and group (war). Richard Wrangham of Harvard University is its most prominent promoter. He has long argued that observed chimpanzee violence suggests “a biological drive to war deeply rooted in millions of years of human evolution. Chimpanzees are among humanity’s closest relatives. If they are wired to fight and kill one another, perhaps war is our destiny, too.” 

https://news.mongabay.com/2014/12/tribal-violence-comes-naturally-to-chimpanzees/

Wrangham’s claim is grounded on a deeply flawed logic. It also is ignorant of military history and organization, and zoology beyond the chimpanzee tales he fixes on. Moreover, its empirical data is badly skewed. The bonobos are biologically just as close to us as chimpanzees – and they are Quakers. They will do just about anything to avoid a fight – within the group, with other groups. When a migrating ‘foreign’ band appears that might create a territorial dispute, they either allow it to pass through their territory peaceably or sometimes they unite. NO warring. So where is this evolutionary “biological drive?” Other great apes – orangutans and gorillas – are notable for their equitable temperaments and pacific behavior. They are just one step earlier on the evolutionary tree than chimpanzees and bonobos. It’s chimps that are the outliers on the violence continuum.

Were we to take seriously the idea that we are born killers with an instinct for violence and war, then the organization and conduct of war would be radically different from what we’ve observed for four millennia. Neolithic peoples would not find it expedient to imbibe various intoxicating substances before going into battle. More modern armies would not have had to be arrayed in static ranks, and overseen by officers ready to impose disciple, if the foot soldiers were chomping at the bit to come to grips with the enemy. Instead, they would be in a frenzy with blood lust. In the 20th century, you wouldn’t have had so many American soldiers ducking-and-covering. And you wouldn’t have PTSD.

Finally, if their thesis about humans “hard-wired’ to be violent and war-like were correct, it would directly contradict the fundamental evolutionary principle of gene preservation and promotion. War between groups – especially if unrelated to basic survival needs and the enemy represented by an assemblage of anonymous persons – has just the opposite effect. It terminates your genetic line at a young age without conferring a genetic advantage on a superior individual survivor. Simply put, survivors of combat are not genetically fitter than the dead. From the perspective of our genes, the more you do to avoid fatal injury the better. For them, a Bronze Star’s value is close to zero; after all, we are just the vehicle for their perpetuation

2] Some might note other candidate “exceptions.” The most commonly referred to is the battle of Ain Jalut where the Crusaders entered into a tacit alliance with the Mamluks to defeat the Mongols in Syria. However, that was case where the invaders had been greatly diminished when their main force, led by Helugu, hastily left the Middle East to deal with a succession crisis back in Karakorum. The other cited instance is the battle of the Catalaunian Plains near Châteaudun in modern day France where the Huns were defeated by a coalition of Romans, Franks and Goths. That Hun army, though, was composed mainly of infantry drawn from what had become a sedentary population settled on the Hungarian plain.

*Gunpowder originally was developed by the Taoists for medicinal purposes. Its first recorded use for warfare was around 904 CE in China. In the 13th century, it was introduced into the Islamic world by the Mongols. It subsequently spread around the Mediterranean and into Europe at a relatively slow pace. The main refinements were made by the Ottomans around 1500. The early firearms’ limited accuracy and range meant that the explosive propelling of deadly balls did not have a dramatic impact on warfare for centuries.