A History of Warfare

by John Keegan

  The causes underlying the operation of ‘permanent’ and ‘contingent’ factors on warfare may therefore be seen to be exceedingly complex. Man the warmaker is not an agent of unbounded free will, even though in warmaking he may burst the limits that convention and material prudence normally impose on his behaviour. War is always limited, not because man chooses to make it so, but because nature determines that it shall be. King Lear, railing at his enemies, may have threatened to ‘do such things — what they are yet I know not — but they shall be the terrors of the earth’; as other potentates in straitened circumstances have found, however, the terrors of the earth are hard to conjure up. Wealth lacks, the weather worsens, the seasons turn, the will of friends and allies fails, human nature itself may revolt against the hardships that strife demands.

  Half of human nature — the female half — is in any case highly ambivalent about warmaking. Women may be both the cause or pretext of warmaking — wife-stealing is a principal source of conflict in primitive societies — and can be the instigators of violence in an extreme form: Lady Macbeth is a type who strikes a universal chord of recognition; they can also be remarkably hard-hearted mothers of warriors, some apparently preferring the pain of bereavement to the shame of accepting the homeward return of a coward.13 Women can, moreover, make positively messianic war leaders, evoking through the interaction of the complex chemistry of femininity with masculine responses a degree of loyalty and self-sacrifice from their male followers which a man might well fail to call forth.14 Warfare is, nevertheless, the one human activity from which women, with the most insignificant exceptions, have always and everywhere stood apart. Women look to men to protect them from danger, and bitterly reproach them when they fail as defenders. Women have followed the drum, nursed the wounded, tended the fields and herded the flocks when the man of the family has followed his leader, have even dug the trenches for men to defend and laboured in the workshops to send them their weapons. Women, however, do not fight. They rarely fight among themselves and they never, in any military sense, fight men. If warfare is as old as history and as universal as mankind, we must now enter the supremely important limitation that it is an entirely masculine activity.

  * Adrianople I was fought between the Roman Emperor Constantine and the pretender Licinius, who approached from west and east respectively; at Adrianople II, 378, one of the catastrophes of history, the Emperor Valens and the last great Roman army were overwhelmed by the Goths, who had invaded the empire across the Danube (in flight from the Huns, a horse people, who had broken out of the steppe); at Adrianople III, 718, the recently arrived Bulgars defeated a Muslim army attempting to take Constantinople from the rear — an outcome of crucial importance for Christian Europe; Adrianople IV, V and VI were fought by the Bulgars in their attempts to attack Constantinople, in 813, 914 and 1003; Adrianople VII, 1094, was a battle between a Byzantine emperor and a pretender; at Adrianople VIII, 1205, the Bulgars defeated the Crusader Baldwin, who had made himself Byzantine emperor, and the Doge Dandolo (whose family house in Venice is now that city’s most expensive hotel); Adrianople IX, 1224, ended in a victory by the restored Byzantine imperial house over the Bulgars; Adrianople X, 1255, was an internal Byzantine struggle; Adrianople XI, 1355, ended in victory by the Byzantines over the Serbs, who had recently become a Balkan military power; Adrianople XII, 1365, marked a successful stage in the Ottomans’ advance from Asia Minor into Europe; following the consolidation of Ottoman power, there was no further battle until 1829, when at Adrianople XIII a Russian army took the city from them; in the last two battles, in 1913, Ottoman Turkey first lost and then regained Adrianople from the Serbs and Bulgars.

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  Stone

  WHY DO MEN FIGHT?

  WHY DO MEN FIGHT? Did men wage war in the Stone Age, or was early man unaggressive? Men — but also women — fight, with ink and paper, very fiercely over these questions. They are not the military historians, who rarely concern themselves with the well-springs of the activities they chronicle, but the social and behavioural scientists. Perhaps military historians would be better historians if they did take time to reflect on what it is that disposes men to kill each other. The social and behavioural scientists have no choice but to do so. Man and society are their subjects, yet most human beings for most of the time cooperate for the common good. Cooperativeness must be taken as the norm, and why that should be so requires some explanation, though of no very profound sort, since common observation will establish that cooperation is in the common interest. If there were no departure from the cooperative principle, therefore, social and behavioural scientists would have little to do. They would be explaining the predictable, an unrewarding and unrewarded task. It is the unpredictability of human behaviour, in individuals and in human groups, which challenges them to supply explanations, and the unpredictability of violent behaviour most of all. The violent individual is the principal threat to the norm of cooperativeness within groups, the violent group the principal cause of disruption in wider society.

  Studies of individual and group behaviour take different directions. They share, however, a common ground, to which debate eventually returns: is man violent by nature or is his potentiality for violence — about such potentiality there can be no dispute, if only because man can kick and bite — translated into use by the operation of material factors? Those who hold to the latter view, loosely categorised as ‘materialists’, believe that their perceptions demolish the naturalist position. The naturalists unite to oppose the materialists but divide sharply between themselves. There is a minority whose members insist that man is naturally violent; though most would not concede the analogy, theirs is the argument of Christian theologians who hold to the story of the Fall and the doctrine of original sin. The majority reject such a characterisation. They regard violent behaviour either as an aberrant activity in flawed individuals or as a response to particular sorts of provocation or stimulation, the inference being that if such triggers to violence can be identified and palliated or eliminated, violence can be banished from human intercourse. The debate between the two schools of naturalists has aroused strong passions. At a meeting at Seville University in May 1986, a majority of those present issued a statement, modelled on the United Nations Educational, Scientific and Cultural Organisation’s Statement on Race, condemning belief in man’s violent nature in absolute terms. The Seville Statement contains five articles, each beginning ‘It is scientifically incorrect’, to which affirmation is expected. The articles together amount to a condemnation of all characterisations of man as naturally violent. In succession they deny that ‘we have inherited a tendency to make war from our animal ancestors’ or that ‘war or any other violent behaviour is genetically programmed into our human nature’ or that ‘in the course of human evolution there has been a selection for aggressive behaviour more than for other kinds of behaviour’ or that ‘humans have a “violent” brain’ or, finally, that ‘war is caused by “instinct” or any single motivation’.1

  The Seville Statement has found weighty support. It has, for example, been adopted by the American Anthropological Association. It does not, however, much help the layman who is aware that war has ancient origins, knows that surviving ‘Stone Age’ peoples like the highlanders of New Guinea are undeniably warlike, is conscious of violent impulses in himself but lacks the expert knowledge of genetics or neurology necessary to take sides. Yet the debate between the two naturalist parties is important, indeed fundamental, as is that between the naturalists and the materialists. At a hopeful time in human history, a time of effective disarmament and of the adoption of humanitarianism as a principle in world affairs, the layman naturally seeks reassurance that the drafters of the Seville Statement have right on their side. Mankind’s success over the the last two centuries in altering for the better the material circumstances of life would then encourage support for the materialists’ explanation of organised human violence, in the anticipation that a continuation of the efforts t
hat have largely defeated disease, want, ignorance and the hardship of manual labour might eliminate warfare also. Its history, from the Stone Age onward, would then become an antiquarian interest, of no more relevance to everyday life than that of world exploration or of pre-Newtonian science. If, on the other hand, the drafters’ of the Seville Statement are wrong, if their condemnations of the naturalist explanation of human violence are mere expressions of optimism, then the materialist explanation is wrong as well, and our end-of-the-century expectations of an end to war entirely misplaced. It is important to know what both the pessimists and the optimists in the naturalist school have to say.

  WAR AND HUMAN NATURE

  The scientific study of violence and human nature centres on investigation of what scientists, perhaps by prejudgement, denote as ‘the seat of aggression’, found in the area of the brain known as the limbic system. This area, located low in the central brain, contains three groups of cells, known as the hypothalamus, the septum and the amygdala. Each, when damaged or electrically stimulated, produces changes in the behaviour of the subject. Damage to part of the hypothalamus of male rats, for example, reduces their aggressive behaviour and abolishes sexual performance, while electrical stimulation increases aggression — though ‘stimulated animals attack only [less] dominant animals, which shows that the direction of aggression is controlled by another part of the brain’.2 The reference to less dominant animals is important, because it is an observation of great antiquity that groups of gregarious animals arrange themselves into a pecking order, so called from hierarchy among domestic fowl, asserting or conceding rank in accordance with it. Damage to the amygdala of monkeys may decrease fear of and therefore aggressive behaviour towards ‘novel or unusual objects’ but increase fear of fellow monkeys, thus causing the damaged animal to lose rank in its group.

  Neurologists cautiously conclude that the reactions to fear, aversion or threat that resolve themselves as aggression — but also as defence — have their origin in the limbic system. They also emphasise, however, the complex relationship of that system with the ‘higher’ parts of the brain, such as the frontal lobes where incoming sensory information is first and most elaborately processed. The frontal lobes, according to A.J. Herbert, appear to be responsible for the ‘regulation and use of aggressive behaviour’, since it is known that damage to the frontal lobes in man may cause ‘uncontrollable outbursts of explosive aggression … not followed by remorse’.3 What neurologists have established, crudely speaking, is that aggression is a function of the lower brain, amenable to control by the higher brain. But how do the different parts of the brain communicate? Two means are through chemical transmitters and hormones. Scientists have discovered that reducing a chemical called serotonin heightens aggression, and they suspect that there may be a peptide which induces its flow. The peptide, however, has not been found, and variations in the level of serotonin are rare. Hormones, the secretions of the ductless glands, are by contrast easily identifiable and one of them, testosterone, produced in the male testes and closely identified with aggressive behaviour, varies widely in concentration. Its administration to humans — whether male or female — heightens aggression. On the other hand, its administration to female rats that are nursing young reduces their aggressiveness towards males, while their maternal protectiveness is stimulated by another hormone altogether. Generally speaking, high levels of testosterone in males make for heightened masculinity, of which aggressiveness is one feature; low levels, however, do not correlate with an absence of courage or combativeness. Evidence for that, for example, is found in the reputation of eunuch bodyguards and the successes of the famous Byzantine eunuch general, Narses. Finally, scientists emphasise, hormonal effects tend to be moderated by context; calculations of risk, that is to say, will offset, both in animals and man, the operation of what may be called instinct.

  Neurology has not, in short, yet succeeded in clarifying how aggression is generated or how controlled within the brain. In genetics, on the other hand, there has been some success in showing how context and ‘selection for aggression’ correlate. Since Darwin first proposed the idea of natural selection in 1858, scholars in many disciplines have sought to establish it on an incontestable scientific basis. Darwin’s original work was based merely on the external observation of species, which led him to suggest that individuals best adapted to their surroundings were the more likely to survive to and in maturity, that the offspring of such survivors, by inheriting their parents’ characteristics, would survive in larger numbers than those of the less well adapted, and that their inherited characteristics would eventually dominate within the species as a whole. What made his theory revolutionary was the argument that the process was mechanistic. Parents, he stated, could pass on only those characteristics they inherited, not — as his contemporary Lamarck contested — those that they acquired. How such characteristics underwent change for yet better adaptation — by the process we call ‘mutation’ — he could not yet explain. Indeed, there is still no explanation of how mutation occurred in the primary organisms from which the myriad varieties of species descend.

  Mutation is nevertheless an observable phenomenon; mutation for aggression is one of its forms and aggressiveness is clearly a genetic inheritance that may enhance the chance of survival. If life is a struggle, then those who best resist hostile circumstances are likely to live the longest and produce the largest number of resistant offspring; a recent and enormously popular book, The Selfish Gene, by Richard Dawkins, ascribes this process not merely to the product of genetic inheritance but to the gene itself.4 Genetic experimentation, moreover, demonstrates that some strains of laboratory animals are verifiably more aggressive than others and that aggressiveness breeds true into subsequent generations. Geneticists have also identified rare forms of genetic constitution which correlate with exaggerated aggressiveness, the best known of which is the XYY chromosome pattern in human males: about one male in a thousand inherits two Y chromosomes rather than the normal one, and the XYY group yields a slightly disproportionate number of violent criminals.5

  Evidence culled from genetic exceptions and even more so from animals bred in laboratory conditions does not, however, supply answers to questions about the aggressive disposition of any existing creature, including man, in its environment. Successful adaptation through mutation, however mutation occurs, is a response to environment, or context, and while it might prove possible, through the new science of genetic engineering, to make ‘point mutations’ in a genetic inheritance and so breed creatures which lack aggressive responses altogether, it would be necessary for their survival to hold them in conditions from which all threat was entirely absent. No such conditions exist in the natural world, nor could they be created. Even were a wholly unaggressive breed of humans to evolve to live in wholly benevolent circumstances, they would still be obliged to kill the lower organisms that cause disease, the insects and small animals that harbour them and the larger animals which compete for food supplies in the stock of vegetation. It is difficult to see how the necessary system of environmental control could be carried on by creatures which lacked aggressive responses altogether.

  What is apparent is that the opponents and the proponents of the thesis that ‘man is naturally aggressive’ both pitch their case too strong. Opponents fly in the face of common sense. Observation demonstrates that animals kill members of other species and also fight among themselves; the males of some species fight to the death. It is necessary to deny all genetic connection between man and the rest of the animal world — a position now held only by strict Creationists — in order to discount the possibility that aggression may be part of man’s genetic inheritance. Proponents also go too far, though for different reasons. One is that they tend to draw the boundaries of aggressiveness too wide. Thus a major group of classifiers, who uncontroversially differentiate between ‘instrumental or specific aggression’, defined as ‘concerned with obtaining or retaining particular objects or position
s or access to desirable activities’ and ‘hostile or teasing aggression’, which is ‘directed primarily towards annoying or injuring another individual’, also include ‘defensive or reactive aggression’ which is ‘provoked by the actions of others’.6 There is a logical distinction, of course, between aggression and self-defence, which is not invalidated even if the classifiers can show that all three sorts of behaviour they classify together have their origin in the same area of the brain. Such indifferentism also suggests that the proponents of the view that man is naturally aggressive give too little importance to the moderating influence of parts of the brain beyond the limbic system. As has been observed, ‘all animals which show aggressive behaviour carry a number of genes which modify its level of expression’ — so that aggressive impulses are offset by calculation of risk or by matching threat to chance of escape, in the well known ‘fight/flight’ patterns of behaviour — the ability to modify the expression of aggression being particularly marked in humans.7 It seems, therefore, that scientists have so far done little more than identify and categorise emotions and responses which have been eternally familiar. True, we now know that fear and rage have a neural seat in the lower part of the brain, that it is stimulated by the identification of threat in the higher part of the brain, that the two neural areas communicate through chemical and hormonal links and that certain genetic inheritances predispose towards greater or lesser violent response. What science cannot predict is when any individual will display violence. What, finally, science does not explain is why groups of individuals combine to fight others. For some explanation of that phenomenon, in which lie the roots of war, we have to turn elsewhere, to psychology, ethology and anthropology.