I

The Oxford English Dictionary defines war as ‘hostile contention by means of armed forces, carried on between nations, states, or rulers, or between parties of the same nation or state; the employment of armed forces against a foreign power, or against an opposing party in the state.’ This is a good beginning, but only a beginning, toward how we should understand war. War is organized violence by voluntary, conscripted, or mercenary armed forces; planned by the leaders of a nation or a group; involves the use of weapons; aimed at an enemy; and may be offensive or defensive. In the narrow sense, war is waged by the armed forces of one nation against the armed forces of another nation. In the wide sense, war may also be waged by clandestine resistance fighters, guerillas, partisans, terrorists, crime syndicates, warlords and their followers; it may be civil, religious, ethnic, or tribal; it may take the form of terrorism, genocide, and massacres; it may be waged by armed forces against a group of fellow citizens or against some transnational group; the enemy aimed at may or may not be armed or organized and may or may not include civilians; and the violence involves killing, disabling, and generally subduing the enemy. Throughout this paper I will understand war in the wide sense.

War has been and continues to be a ubiquitous feature of the human condition. Virtually all nations were formed by war and waged many defensive and offensive wars in the course of their history. There are no nations without armed forces and there are no groups who do not rely on their own or on their nation's armed forces. The frequency of war and the casualties caused by it have not diminished in time. In fact, ‘the hundred years after 1900 were without question the bloodiest in modern history, far more violent in relative as well as absolute terms than any previous era … By any measure, the Second World War was the greatest man-made catastrophe of all time.’Footnote ¹ ‘There is no question that the twentieth century witnessed a mind-bogglingly large number of deaths by organized violence. Estimates for the total number … range from 167 million to 188 million.’Footnote ² ‘Archeological, anthropological, as well as all surviving documentary evidence indicates that war, armed conflict between organized political groups, has been the universal norm in human history.’Footnote ³ War is a permanent adversity, and the aim of this paper is to try to understand why it has been that and why it is likely to remain so. Much has been written about the justification of war,Footnote ⁴ but my concern here is with the causes of wars, not with their justification.

The violent actions of war are the actions of individual human beings directed against other human beings. These agents, however, are not acting on their own behalf, but as ordered by their commanders who are executing a policy that the war implements. Understanding war is not merely a matter of understanding why individuals kill, maim, or disable other individuals, but understanding the policy that their violent actions implement. The policy would be useless, of course, if individuals were not willing – often because forced – to implement it, but war involves the organized and coordinated actions of individuals. Understanding war, therefore, must involve understanding why the leaders adopt the policies that the collective actions of individuals implement. The leaders know that implementing the policy involves the use of considerable resources much needed elsewhere, that it will lead to extensive casualties, and that it puts at risk the very survival of their own nation or the group. They nevertheless accept the considerable costs and risks involved in war. Why?

In some cases the explanation is obvious: the leaders have no choice. Their nation or group has been attacked and its survival depends on defending itself. But such cases explain very little. War always involves at least two sides, and typically one of them attacks and the other defends. Understanding war requires understanding the policies that lead one side to attack the other. Offensive war, however, is often a response to being threatened, challenged, or provoked by the defending nation or group, or it is a preemptive response to anticipated attack. Such considerations make it unclear just which side is waging war offensively and which does it defensively. Hostilities between nations and groups typically have a long history whose rights and wrongs are lost in the misty past. Furthermore, it is rare if the leaders of a defending nation or group have no choice. They can meet whatever demands the attackers have, or seek a compromise, or surrender. Waging either offensive or defensive war is almost always a matter of choice between available options. Why do the leaders opt for war rather than for one of the other available options? Moreover, opting for war involves the certainty that many people on both sides will be killed, maimed, or otherwise disabled. The protection of human life, however, is a basic value embedded in the law, morality, and religion of virtually all nations and groups. Why do the leaders choose the option that unavoidably involves systematic and large-scale actions that would normally be condemned as violations of legal, moral, or religious prohibitions?

Attempted explanations of war may be distinguished on the basis of the type of cause they identify as responsible for war. One largely environmental explanation treats war as the effect of competition for scarce resources. Another mainly evolutionary explanation claims that war is the consequence of human aggressiveness. And a third predominantly historical explanation begins with the claim that war is the result of the quest for power and goes on from there. I will argue that none of these explanations is adequate, and propose a better one that develops further the historical explanation. I conclude that war is a permanent adversity.

II

The first explanation I consider is Steven A. LeBlanc's.Footnote ⁵ He is an archeologist and bases his theory on extensive archeological and anthropological evidence. He writes that the wars ‘we find today fit into patterns of human behavior that have gone on for millions of years … and continue to do so for the same reasons they did in the past. Much of today's warfare reads just like the warfare of tens of thousands of years ago – the same causes, the same tactics, and the same attitudes’ (LeBlanc, xi–xii). His explanation is that ‘warfare has, in fact, been based on rational behavior for much of human history … [it] has ultimately been a constant battle over scarce resources throughout the ages’ (230). He recognizes that the scarcity of resources has different causes in different circumstances: it may be the growth of population, or ecological imbalance created by increasingly efficient hunting, or the exhaustion of land by shortsighted agricultural practices, or climatic changes affecting the food supply, and so forth. But whatever is the cause of scarcity, war is violent competition for scarce resources. The competition may be between stationary groups who rely on the same resources, or between a more mobile group that has moved into a territory and a stationary group that has long resided in it. According to this explanation, whether or not they know it, the reason why groups attack other groups is to alleviate the scarcity of their resources. Parties to war may invent myths about why they fight, but underlying the myths is the hard fact that they fight for scarce resources.

There is no doubt that this explains part of the causes of some wars, provided the competed for resources are understood broadly enough to include women, slaves, water, gold, fertile land, minerals, and whatever else – such as oil or fishing and mining rights – a group may regard as important for the satisfaction of its needs. But there is even less doubt that a great deal is left unexplained. The basic problem is that, although the explanation is supported by evidence derived from a great variety of circumstances, it fails to recognize that many wars are fought in which both sides have ample resources, that war is only one kind of response to the scarcity of resources, and that there are features of war that the explanation does not cover. I will consider these problems in turn.

To begin with, wars of independence, religious, ideological, many ethnic and tribal wars were not fought over scarce resources. The Church mounted the Crusades, not because it was short of resources, but because it regarded heretics and infidels as enemies who challenged the one true faith. The Thirty Year War between Catholics and Protestant was fought for religious domination, and the dire scarcity of resources was not the cause but the effect of it. Napoleon waged wars of conquest, and he and his deluded troops fought for glory and scorned attention to resources. The civil war in Russia after 1917 was fought between defenders and opponents of the revolution, and they fought over the communist rule of Russia, not for resources. Hitler did not attack Poland in search of scarce resources. After India became independent, age-old resentments, repressed under British rule, led Buddhists and Moslems to massacre each other, rather than to expropriate each other's resources. The First and the Second World Wars were contests for the domination of Europe, and both sides had ample resources. The tribal wars in Nigeria, the Congo, Rwanda, and elsewhere in Africa worsened the already great poverty and merely expressed the longstanding reciprocal hatred of the tribes involved. Russia was not and America is not waging war in Afghanistan for available resources, since that impoverished country has nothing the invaders needed or need.

Wars are waged for many reasons, such as conquest, domination, fear, hatred, ideology, independence, power, prejudice, religion, self-determination, territory, and so forth. The competition for scarce resources is only one among many reasons. And it is very rare indeed for any war to be fought only for one reason, or, indeed, that the parties to it are led to fight it for the same reason. LeBlanc's explanation ignores these great historical variations and multiple causes, because he relies on archeological evidence that is unavoidably silent about the psychology of those who fight, the variety of historical influences that have formed them, and the effect of their religious, moral, and political beliefs on how the warring parties perceive their own and their enemy's lives and circumstances. LeBlanc almost acknowledges this when he says that ‘assessing the social factors relating to warfare turns out to be increasingly difficult as societies become more complex … as groups grow larger and more complexly organized, it becomes progressively easier for warfare to be considered “irrational”, based on flawed judgments at the leadership level’ (LeBlanc, 214). To say that such wars are irrational, is to admit that his simple explanation does not cover them, and that LeBlanc does not know why complex societies fight wars. But that is plainly inconsistent with his overall claim that ‘much of today's warfare reads just like the warfare of tens of thousands of years ago – the same causes, the same tactics, and the same attitudes’ (LeBlanc, xi–xii).

Nor is war the only possible response to the scarcity of resources. The shortage of food supply often led hunting-gathering groups to settle down and become agricultural. After losing an empire, Spain turned inward, cultivated religious devotion, and for centuries accepted poverty. The Dutch overcame the scarcity of their resources by becoming one of the historically most successful trading nations. Many African nations preferred independence even though it doomed them to continued poverty. Greece, Ireland, and Portugal responded to longstanding scarcity of resources by joining what was then the Common Market. The Swiss responded by specializing in light industry. The Estonians and Slovenians overcame the consequences of ruinous central planning imposed on them and developed a vibrant economy. Even in cases when groups attempt to overcome the scarcity of their resources by waging war, their neediness cannot be the sole cause of war, because, as these examples show, there are typically options other than resorting to war. Nations, tribes, groups can often improve their economic conditions by peaceful means. If they endeavor to improve it by war, it needs to be explained why they choose that option and reject alternative possibilities. LeBlanc's proposed explanation does not do that.

It is another defect of this explanation that it does not account for the fact that numerous wars are waged with much greater savagery than what is needed for obtaining whatever resources the war is fought war. The victors in a war could just expropriate the resources and disarm those they have defeated without having to murder, torture, or mutilate them. The satisfaction of the victors' economic needs does not depend on murdering women and children, or on destroying the conditions on which the dignity and livelihood of the defeated group depends. Yet the victors are often concerned with punishing, humiliating, and breaking the will of their subdued enemies. And they are often bent on mistreating them in such ways even though it consumes a considerable portion of the resources for which they have allegedly waged the war.

If, then, this explanation is as defective as these considerations show, it may be asked whether there is any point in discussing it. The point is that by understanding its defects we can identify some of the conditions that an improved explanation must meet. The explanation is correct in recognizing that environmental conditions are typically among the causes of wars. The proximity and accessibility of the enemy, the training of the armed forces, the available weaponry, the means of supplying the fighters, the condition of the roads, and, of course, the needs of the attackers are typically parts of a satisfactory explanation. But they are only parts. For the attackers must evaluate these environmental conditions as favorable, or at least acceptable, and their evaluations will reflect their history and experiences, as informed by their religious, moral, and political values. An improved explanation must take these considerations into account. Consequently, it cannot be only external and environmental, but must also include internal and psychological conditions. I now turn to another explanation that does includes these conditions, but it remains nevertheless defective in ways that reveal some additional conditions a successful explanation must meet.

III

The explanation I now consider seeks the causes of war in human nature. It is, thus, an internal, psychological explanation. It recognizes that environmental conditions are relevant to explaining the causes of war, but it treats them as relevant only in the sense that they trigger dispositions inherent in human nature. The explanations of war by Thucydides, Machiavelli, and Hobbes are of this type, but their contemporary followers insist on the importance of two further considerations, which were unavailable to these classical writers and which, they claim, greatly strengthen the plausibility of this type of explanation. One is understanding human nature in evolutionary terms, and the other is recognizing the centrality of the structure and complexity of the brain to the evolutionary explanation of human nature, and thus of war. The contemporary extension of the classical explanation was made possible by the development of biology and cognitive science. In two important recent books, a philosopher and a political scientist each immersed himself in these two sciences in order to explore their implications for the explanation of war. The books are by Stephen Peter Rosen and David Livingstone Smith.Footnote ⁶

Rosen says that ‘the argument of this book is, in its essence, reasonably simple. It includes biological issues, but it is not a biological determinist argument. Human beings have several mechanisms inside them that play a role in decision making. These multiple mechanisms exist as a result of our biological inheritance… In short, this book tries to make the case that there is a biological argument that Thucydides was right… This book uses the current scientific understanding of human nature, along with an understanding of social institutions, to explain human cognition as it is relevant to the issues of war and peace’ (Rosen, 2–3). And Smith says that ‘to understand war, we need to find its place in the grand saga of evolution. We must tease out its deep biological roots by examining the role of aggression in the lives of nonhuman species how this heritage was transformed as our ancestors evolved into human beings’ (Smith, 71). What enables this teasing out is ‘sleek technologies for brain imaging [that] now allow scientists to peer into living brains in real time, sophisticated methods of experimental psychology enable them to study mental processes under controlled laboratory conditions, and mathematical and computational techniques make it possible to precisely model complex patterns of human behavior’ (Smith, 62).

This explanation rests on several assumptions. Human beings have a nature, that is some traits that all and only human beings have. These traits have been formed by an evolutionary process that has taken place during millions of years. The process involved the survival of those who could successfully adapt themselves to their environment and the extinction of those who failed. The survivors reproduced and transmitted to their offspring their traits, among which were ones that enabled them to survive. Essential among these traits was the capacity for the accurate interpretation and successful response to complex information received through the senses. The organ that interprets information and directs the response to it has been the brain. War involves the interpretation of and response to information, therefore the causes of war must be some traits of the brain. Since war has been constant, the traits of the brain that cause it must be enduring parts of human nature. These traits can be jointly referred to as aggressiveness. According to the explanation of war favored by Rosen and Smith and based on the assumptions derived from evolutionary biology and cognitive science, the cause of war is aggressiveness.

Rosen and Smith are scrupulous in acknowledging that this explanation is hypothetical, because the theories it draws on are incomplete. The human genetic code has been only very partially deciphered, the brain is an immensely complex organ, cognitive science is in its infancy, and so are the mathematical and computational techniques that enable the modeling of the relevant traits of the brain. They nevertheless believe that whatever evidence has emerged supports this explanation. Bearing all this in mind and granting the controversial assumptions on which the explanation rests, I will consider the origins of the First World War in order to see whether the explanation helps to understand its causes.

In 1914 the Austrian heir to the throne was assassinated in Sarajevo. This occurred at an exceptionally tense period in European history. The block formed of Austria, Germany, and a few smaller nations, was at odds with the block formed of Russia, France, England, and their smaller allies. The nations in each block were obliged by treaty to come to each other's military aid in case of attack; they were all heavily armed; and committed, as nations always have been, to protect by one means or another what they saw as their interests. The leaders of Austria decided to respond to Serbia where the assassination took place by issuing an ultimatum. Serbia rejected it. Austria then went to war against Serbia. Russia came to the aid of Serbia. Germany came to the aid of Austria. And France and England responded by coming to the aid of Russia. And so the war began.

Countless learned tomes have been written about what exactly happened, what motivated the warring nations, how rational or irrational their decisions were, and how much responsibility each bore for the unprecedented carnage that ensued. I leave all these questions aside and consider some aspects of the decisions the leaders had to make. The leaders of all the nations involved had to decide among available options: honoring their treaty obligations and entering the war, reneging in the interest of peace, entering into diplomatic negotiations, urging their allies to compromise, and so forth. Their decisions had to take into account how the other involved parties would be likely to decide among the available options. The leaders had to estimate the duration and costs of the war, the chances of victory and defeat, and the consequences of both. They had to rely on the advice of their military strategists and they had to evaluate the reliability of the advice they got. They had to gauge the extent to which the citizens they ruled would support or oppose the various options they might choose. They had to pull all of these uncertain estimates together and weigh their relative overall importance. And the leaders of each nation had to settle the internal disagreements among themselves between those who favored war, or peace, or diplomacy, or some kind of negotiated compromise.

These decisions were, of course, immensely complex and much depended on making the right one. But their complexity was greatly increased by factors of which the leaders may or may not have been aware, or may have been more or less aware. They could not just have said: on balance this is the right decision and let us act on it. For the rightness or wrongness of all decisions essentially depended on what decisions the leaders of the other nations would make, and the same was true of the decisions of all the leaders of all the nations involved. Furthermore, the rightness or wrongness of the decisions was not just a matter of pragmatically weighing the costs and benefits of the various options. That certainly mattered, but it was not the only thing that mattered. The decisions were influenced by how the leaders saw the historical relationship between their own and the other nations involved. It influenced them whether they had been allies or enemies, whether they won or lost in past conflicts, whether they had commercial ties on which the prosperity of their nation depended. There were considerations of honor, loyalty, patriotism, revenge, and xenophobia involved. And the leaders were not just calculating machines, but people with religious and moral beliefs. They were educated, had a historical perspective, and they knew that the decision they had to make will have great historical significance. They wanted to do the right thing for the nation they ruled, but they also cared about the larger interests of European civilization, of the even larger one of humanity, and they would not have been human if they had not cared about their own personal interests. These considerations inclined them in different directions.Footnote ⁷

The complexity of these decisions is not just a result of the complexity of the relevant facts and imperfect knowledge of them, but also of the unavoidable necessity of having to interpret the facts in the light of historical, moral, and religious values. It is typical of these decisions that even if those who have to make them were to agree about the facts, unlikely as that is, they would still routinely disagree about how the facts should be interpreted, because they were committed to different values. I merely note this here, but will return to it shortly.

Let us now consider Rosen's and Smith's explanation of war in the light of these complex decisions. Their explanation is that the leaders have decided in favor of war, because they were motivated by aggressiveness, which, in the course of evolution, has become a trait of the human brain and thus of human nature. This explanation is clearly an improvement over LeBlanc's, because it explains not only why people respond aggressively to the shortage of resources, but also to any challenge they may face. Nevertheless, the explanation is untenable even if the controversial assumptions on which it rests are accepted.

Let us grant that aggressiveness was one of the motives that led the leaders to enter into the First World War. But they obviously had other motives as well, such as historical considerations, their estimate of what the attitude citizens of their own nation would be toward the war and of the military capacities of all likely participants; honor; the interest of their nation; their judgment of what other nations will do; their moral and religious values; prudence; treaty obligations; and so forth. This complexity creates a dilemma for those who favor the evolutionary, cognitive scientific explanation of war.

If their explanation is that aggressiveness imprinted in the human brain was the deep master trait underlying all these other motives, then the explanation is mistaken. For, with the exception of some German leaders, none of the leaders of any of the participating nations favored war. There were also nations – Spain, Sweden, and Switzerland, among others – whose leaders decided against entering the war. Even if aggressiveness is imprinted in all human brains, it is clearly not always the master trait on which we always act. If, on the other hand, the explanation of Rosen and Smith is that aggressiveness is merely one motive among others, then their explanation is incomplete. It does not answer the obvious question of why some people sometimes do and sometimes do not act on their imprinted trait of aggressiveness. The answer cannot be to hypothesize that there is yet another trait imprinted in the human brain, because the question is why one imprinted trait leads to actions, while another does not. The answer must be that something triggers aggressiveness, and that something must be some feature of the environment to which the person in question is responding. And, in the case of the decision to enter the First World War, that something was not one thing, but the many considerations that made the leaders' decisions as complex as they were. I conclude that the evolutionary, cognitive scientific explanation of the causes of war is either mistaken or incomplete.

The fact is that human aggressiveness is neither a necessary nor a sufficient condition of war. It is not necessary, because many nations fight unwillingly to defend themselves against being attacked. If they had not been attacked, they would not fight. Nor is aggressiveness a sufficient condition of war, because morality, religion, self-interest, or fear may lead nations to suppress their aggressiveness. The most that can be reasonably claimed is that aggressiveness is often a contributing cause of war. That, however, is not exactly news, and it is hard to see why we need the theory of evolution or cognitive science to reinforce what has been patently obvious to historians.

The initial plausibility of this explanation derives from the undeniable fact that war has been a constant feature of our history. War is waged by human beings in a great variety of different times, places, conditions, and cultures. It is not implausible to suppose that something internal, rather than external, to human nature leads to war. Nor is it implausible to call this internal something aggressiveness. But peace, family and communal life, loyalty, the division of labor, and so forth have also been constant features of our history. It is just as plausible to suppose that they also reflect something internal to human nature, which we may call cooperativeness. If there is reason to suppose that aggressiveness has been imprinted in the human brain by millions of years of evolution, then there is reason to suppose that the same is true of cooperativeness. Aggressiveness and cooperativeness, however, motivate us in different, often incompatible, directions. Sometimes one proves stronger, sometimes the other, and sometimes perhaps some other imprinted trait overwhelms both. When this is acknowledged, as it seems reasonable to do, then the initial plausibility of the evolutionary, cognitive scientific explanation of war disappears. The explanation rightly stresses the importance of one motive for war. But it wrongly fails to stress that wealth, security, loyalty to friends, and justice may be other important motives for war, and that the same motives may lead to favoring peace.

The basic reason that counts against LeBlanc's, Rosen's, and Smith's explanations of war is that they are much too simple. They suppose that explaining war depends on finding the cause of war. Wars have many complex causes. If we want to understand the causes of war, we should turn to historians who recognize this. I accept their view that ‘any theory of the causes of war in general or any war in particular that is not inherently eclectic and comprehensive … is bound for that very reason to be wrong’Footnote ⁸ and ‘no single explanation for conflict between states, any more than for conflict between any other social groups, is likely to stand up to critical examination.’Footnote ⁹

IV

The author of the last cited passage is the distinguished military historian, Michael Howard. Shortly after this passage, he quotes what Thucydides says in Book I of the Peloponnesian War of the causes of war between Athens and Sparta: ‘“What made war inevitable was the growth of Athenian power and the fear this caused in Sparta.” And “The Athenians made their Empire more and more strong … until finally the point was reached when Athenian strength attained a peak plain for all to see and the Athenians began to encroach upon Sparta's allies. It was at this point that Sparta felt the position to be no longer tolerable and decided by starting the present war to employ all her energies in attacking and if possible destroying the power of Athens.”’ Howard, then, comments: ‘You can vary the names of the actors, but the model remains a valid one … I am afraid that it still does.’ And he says that the leaders of nations feel ‘justified in going to war, not over any specific issue that could have been settled by negotiation, but to maintain their power, and to do so while it was still possible, before they found themselves so isolated, so impotent, that they had no power left to maintain and had to accept a subordinate position within an international system dominated by their adversaries.’Footnote ¹⁰

Years later Howard adds: ‘The vital questions which confront not only students of war but all concerned with peace and security are, why wars happen … and above all how they can be prevented.’ And he goes on: ‘At one level of analysis the answer to the first question is simple. Wars occur when the established order, the status quo, is forcibly challenged, and the status quo power reacts … There is no war without resistance; but without resistance, and the possibility of resistance, there is no international order. All States … have an interest in their own self-preservation and maintain armed forces with that end in view. One of the basic foundations of the international order is the perceived capacity of States to protect themselves, or to persuade others to do it for them.’Footnote ¹¹

It may seem that Howard's explanation is that the cause of war is struggle for power between two states one of which attacks and the other defends its position in the international order. If this were Howard's explanation, it would be another simple explanation, which, as he says above, will not ‘stand up to critical examination’. And indeed it would not. Religious, ideological, civil, tribal, and ethnic wars often have little to do with the international order and a great deal with the internal order of particular states. But, contrary to appearances, Howard is not offering a simple explanation of the cause of war. He says that ‘I know that this explanation of the phenomenon of war is superficial and simplistic’Footnote ¹² and goes on to indicate the direction in which an improved explanation may be found.

He quotes Clausewitz's claim that war is ‘a clash of major interests that is resolved by bloodshed’, and comments on it that ‘war is only a particular kind of conflict … [and] these conflicts arise from conflicting claims, or interests, or ideologies, or perceptions; and these may indeed be fuelled by social or psychological drives that we do not fully understand … the problem is the control of social conflict as such, not simply of war.’Footnote ¹³ I think this is deeply right. In the rest of this paper I will follow up and develop this and some other intimations I have found in Howard's writings. My reason for doing so is that it brings us to the main purpose of this paper, which is to understand why war is a permanent adversity that stands in the way of the improvement of the human condition.

Howard says that ‘all societies must have some view of the past; one that shapes and is shaped by their collective consciousness, that both reflects and reinforces the value-systems which guide their actions and judgments.’Footnote ¹⁴ Nations and groups within them typically have more or less different systems of value and understanding conflicts among nations and groups depends on understanding their systems of value. Howard stresses ‘the importance of comprehending cultural diversity and equipping oneself to cope with it. Much has properly been made of Neville Chamberlain's failure to understand Hitler, as of Roosevelt's failure to understand Stalin; but these disastrous misunderstandings are often depicted as cases of honest men being outwitted by crooks. Alas, the misunderstanding was at a far deeper level than that.’ It was that these and other leaders had and present ones often still have ‘no awareness … of the historical background, the cultural universe, of the foreign societies with which they have to deal.’ This is a lack for which no amount of archeological, anthropological, evolutionary, cognitive scientific, economic, or strategic analysis can compensate. Not even the most sophisticated mathematical modeling can be a substitute for the imaginative understanding of how the world appears to those who interpret the facts, perhaps the same facts as we do, in the light of a system of values that is very different from our own.

Here are some examples of what I have in mind.Footnote ¹⁵ Given the Western democratic system of values, the disintegration of the Soviet Union, the enlargement of NATO, the independence of Baltic and Central European states reflect the salutary victory of liberty over tyranny. From the Russian point of view, they reflect the shameful surrender to American and European pressure at a time of deplorable Russian weakness. The Western attitude to China's rapid development as a commercial and military power is to regard China as an increasingly equal partner in international affairs, who, just like us, seeks prosperity, recognition, and acceptance. The Chinese look back on their history and see that their ancient civilization was for centuries humiliated by ignorant Western barbarians; that they have been exploited and reduced to poverty by the settlements imposed on them by Western invaders; and that they have been forcibly deprived of the status they had for thousands of years as the dominant power is Asia. They see their growing military and commercial power as means to reclaiming their rightful status, and they see peace, trade, and international order as arrangements that temporarily happen to serve their interests. Similar differences in perception handicap the mutual understanding not just of the West, Russia, and China, but also of India, Japan, Iran, Turkey, Israel, and Arab nations. And these mutual misunderstandings are not just among Western and non-Western nations and groups within them, but also among non-Western nations and groups, as well as among Western ones.

All these nations and groups define themselves by values they derive from their history, religion, ideology, art, classic works, and sacred texts. These values inform their attitudes to authority, customs, death, education, food, illness, law, money, sex, tradition, and work, and so forth; shape what they see as duty, friendship, loyalty, love, obligation, virtuous or vicious; what they find funny, important, obscene, offensive, polite, tolerable, and so forth. Their identity is formed of these values, even if they eventually come to question some of them.

When the interests of nations or groups conflict, they may try to settle their conflicts by negotiation. If their interests do not affect vital matters and if prudence prevails, they may succeed in finding some mutually acceptable compromise. But if vital matters are at stake, they will defend their interests in any way they can, including war. The key to avoiding war is the mutual understanding of the leaders and their representatives of what is and what is not seen by the other as a matter of vital interest. And that understanding is of the system of values that forms their respective identities. When a great deal depends on it and prudence prevails, they may reluctantly consent to compromising their identity, but if the compromise would be destructive of the identity of one or both sides, war will be preferred to it. Many wars have been fought, because the two sides refused to negotiate, or negotiated imprudently, mistakenly regarded non-vital interests as vital, or because the leaders were ignorant, stupid, or irrational and failed to understand the other side. But wars will be fought even if the two sides negotiate prudently, do not exaggerate their interests, and the leaders are well-informed, intelligent, and rational, because some conflicts among different systems of value are irreconcilable and vitally affect the identity of those who see good and evil and the meaning of their lives in terms of their system of values. On those fundamental issues, neither the leaders nor their followers would be willing to compromise. And that is the reason why war will remain a permanent adversity and an unavoidable obstacle to the improvement of the human condition.

V

No one will dispute that war is an adversity, but many will dispute that it is permanent. They will say that war is always caused by the failure of rationality or morality or both at once. If leaders understood the horrors of war and they were rational and moral, they would want to avoid it at all costs. And the many thoughtful people who think this way will probably begin to defend their optimistic illusion by pointing out that democratic nations have never gone to war against each other. This is not, optimists will say, because they have not had conflicting interests, but because they resolved their conflicts by negotiation and compromise, just as rationality and morality require. I accept the point, but deny that it follows from it that war is not a permanent adversity.

It will probably be granted that America, England, and France were the largest and most powerful democracies during the last hundred years. It is quite true that they have not gone to war with one another, even though they had numerous conflicts of interests. They have, however, fought in two world wars, several smaller international wars, as well as in various internal conflicts. The reason why they have not fought each other is that their conflicts of interests were over issues that did not threaten their identity. Their systems of values have overlapped to a large extent, and they could take each others' commitment to it for granted and negotiate and compromise on that basis. But they could not do this with Wilhelmine and Nazi Germany, with Korea, Vietnam, Iraq, and Afghanistan, among others, because the two sides were committed to fundamentally different systems of value.

There is no possibility of compromise and negotiated settlement of conflicts between fundamentalist Moslems and secular Westerners about values that are essential to the conceptions of good and evil and the meaning of life on which their different identities depend; or of conflicts between Israelis and Arabs who deny Israel's right to exist; or of conflicts between the Chinese, who think that the Western insistence on individual rights is an excuse for retarding their growing commercial and military power, and the Westerners, who see the protection of such rights as a condition of civilized life; or of conflicts between democracies and Congolese or Rwandan mass murderers, Iranian ayatollahs, Korean communists, Moslem terrorists, Serbian ethnic cleansers, fundamentalist Taliban fighters, and brainwashed suicide bombers.

Optimists will say, of course, that all this intransigence is irrational and immoral, and the key to the improvement of the human condition is to foster by education, example, and toleration the spread of rationality and morality. But this is a dangerously naïve view. For those who are condemned by the optimists for being irrational and immoral will reject this charge and fight for their values. If they were articulate enough, they would explain that they understand rationality and morality in terms of the system of values that defines their identity. And they would point out that in doing this, they are doing exactly what the optimists are doing with their understanding of rationality and morality. It will not convince them to say that rationality and morality set external standards to which all systems of value ought to conform, because they will ask what the standards are based on. If optimists say that they are based on the requirements of human well-being, then their opponents would reply that the external standards are God's commandments, or the laws of history, or the defense of their religion, ideology, or cause. All that optimists achieve by their naïve view is to make the side they are on less willing to do what is necessary to defend their own system of values. That is why their view is dangerous.

The optimists fail to see that, as history so amply shows, even basic values are plural and conflicting. When nations or groups are pitted against each other, because their basic values lead them to act in ways that they find mutually unacceptable, then they cannot settle their conflict by negotiation and compromise. For what is at stake for them are the basic values that ultimately make their life worth living. And if they are attacked, then they will fight. War is a permanent adversity, because such conflicts are the unavoidable consequences of the plurality of values.

VI

It would be misleading to leave the argument with this relativistic conclusion. I believe that good reasons can be given in support of human well-being as an external standard of rationality and morality. The aim of my argument, however, has not been to defend such a standard, but to show that war is a permanent adversity, because there have been and will continue to be systems of beliefs whose defenders reject the reasons that might be given for the external standard of human well-being. They reject these reasons, because accepting them would threaten their deepest beliefs and their identity, and they would rather accept the horrors of war and fight. This has been a consistent tendency throughout history, and I see no reason to suppose that the future will be different. That is why I think that optimism on this score is naïve and dangerous. We must face the fact that sometimes there is no alternative to waging war in order to defend rationality and morality on which human well-being depends.