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Strategy in the Contemporary World

Strategy in the Contemporary World (6th edn)

John Baylis, James Wirtz, and Colin Gray
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p. 725. The Causes of War and the Conditions of Peacelocked

p. 725. The Causes of War and the Conditions of Peacelocked

  • John Garnett
  •  and John Baylis


This chapter examines theories that explain the causes of war. It considers ideas advanced by political scientists, sociologists, biologists and philosophers, showing that different explanations of war give rise to different requirements or conditions for peace. After highlighting the difficulties in studying war, the chapter discusses human nature explanations of war, citing such factors as frustration, misperception, misunderstanding, miscalculation, and errors of judgement as well as the role of human collectives including factions, tribes, nations and states. It then describes the bargaining model of war before turning to inter-state wars, intra-state conflicts, and ethnic conflicts. It also explores the debate over whether ‘greed’ or ‘grievance’ are the main causes of civil wars. The chapter concludes that identifying a single cause appropriate to all wars is an exercise in futility and that a worldwide ‘just’ peace is unattainable.

Reader’s Guide

Scholarship dealing with the causes of war is voluminous and multidisciplinary. This chapter describes and explains theories that have been advanced by biologists, philosophers, political scientists, and sociologists about why wars occur. It groups their ideas into categories and shows how different explanations of war give rise to different requirements or conditions for peace. The chapter pays particular attention to explanations of war based on human nature and instinct, but it also considers psychological theories that emphasize misperception and frustration as causes of aggression. The ideas of those who find the causes of war in human collectives—states, tribes, and ethnic groups—and those who favour ‘systemic’ rather than ‘unit’ explanations are also described. The chapter also looks at the debate between ‘greed’ and ‘grievance’ as a cause of civil wars.


Though ‘strategy’ these days is as much concerned with the promotion of peace as with the conduct of war, the phenomenon of war remains a central concern. Previous generations might have seen virtues in war, for example as an instrument of change or as a vehicle for encouraging heroic virtues, but these ideas have been rendered obsolete by the destructiveness of modern warfare. In the twentieth century, abolishing war became a top priority. The first step in ending war, however, is to identify its causes.

Historians sometimes argue that since each war is a unique event, the causes of war are as numerous as the number of wars and nothing general can be said about them. This chapter takes a different view. It identifies similarities and patterns between the causes of wars so that we can group causes under such headings as human nature, misperception, the nature of p. 73states, and the structure of the international system. Its aim is twofold. First, to relate contemporary scholarship across a range of disciplines—biology, political science, philosophy, and history—to the problem of war causation, and second, to elaborate a number of distinctions which help us to identify different kinds of ‘causes’ (e.g. underlying and immediate causes). Throughout the chapter these distinctions are used to identify the various causes of war and to discriminate between them.

Since there is little scholarly agreement on what causes war, this chapter is directed towards explaining the debate rather than answering the question in a decisive way. The arguments are more than academic because, if the cure for war is related to its causes, then different causes will lead to different policy recommendations. If, on the one hand, wars are caused by arms races, then policies of disarmament and arms control are appropriate solutions to the problem of war. On the other hand, if wars are instigated by despotic or authoritarian states, then the way to peace lies in the spread of democracy. If the basic cause of war is deemed to be the ‘international anarchy’ which characterizes the current system of states, then attempts to rid the world of war will be geared towards promoting system change—perhaps in the direction of strengthened international law or a system of collective security or world government. Some explanations for war offer less hope than others for finding a way to end armed conflict. For example, those that locate war in a fundamentally flawed human nature suggest a bleaker future for the human race than those that locate the causes of war in learned behaviour. If war is learned rather than instinctive, then there is a possibility that it can be eliminated through social engineering.

Three conclusions emerge from this analysis. First, the search for a single cause appropriate to all wars is futile. Second, because war comes in a variety of forms and has a multiplicity of causes, its elimination will almost certainly require simultaneous domestic and international political action. Third, a world-wide ‘just’ peace is unattainable.

The Study of War

In the field of international relations, no question has attracted more attention than ‘Why war?’ The reason for this interest is that war is almost universally regarded as a human disaster, a source of misery on a catastrophic scale, and, in the nuclear age, a threat to the entire human race. But war has not always been viewed so negatively. In the nineteenth century, for example, numerous writers identified virtues in war (see the Introduction). The philosopher G. W. F. Hegel believed that war preserved the ethical health of nations, and in a similar vein H. von Treitschke regarded war as ‘the only remedy for ailing nations’ (Gowans 1914: 23). For Treitschke, war was one of the conditions for progress, the cut of the whip that prevents a country from going to sleep, forcing satisfied mediocrity to leave its apathy. This kind of thinking alerts us to the idea that war can be thought of as a purposive, functional thing. E. H. Carr regarded it as ‘the midwife of change’ (1942: 3): ‘Wars … break up and sweep away the half-rotted structures of an old social and political order.’ These authors suggested that wars herald rapid technological progress, territorial change, strengthened group consciousness, and economic development. The idea of war as a purposive, functional thing, however, sits uneasily in an age that typically interprets war as an abnormal, pathological condition that threatens us all.

p. 74Idle curiosity or an aimless spirit of enquiry has not been the motivation behind most investigations into the causes of war. Theorists have studied war to abolish it. They have believed that the first step towards eliminating war is to identify its causes because, in much the same way that the cures for disease are related to the causes of disease, so the cures for war are to be found in its causes. As long as students of war do not allow their enthusiasm for prescription to affect their diagnostic skills, no harm is done. However, there is a danger that researchers may be tempted to gloss over the more intractable causes of war in favour of those which suggest the possibility that solutions to human conflict can be readily found.

Many social scientists recoil from the idea that though particular wars may be avoided, war is endemic in the human condition. The idea that war is inevitable is pretty difficult to swallow, psychologically speaking, and that may explain why pessimistic interpretations of the causes of war meet with resistance. Take, for example, the view that the root cause of war is to be found in human nature, i.e. that aggression and violence are genetically built into humans and that we do what we do because of what we are. Despite some scientific evidence in support of this idea, there is enormous resistance to it. Why? Because, if human nature is fixed in our genes, we are helpless in the face of ourselves. For many observers, the conclusion that war is built into us is an intolerable counsel of despair, even though it is a useful reminder that just because the elimination of war is desirable does not mean that it is therefore possible.

A gloomy interpretation of human nature and an admission of its intractability, however, do not automatically lead to despair of ever being able to rid the world of war. Some would argue that wars are not caused by human nature; they are caused by human behaviour. And while it may not be possible to change human nature, it is certainly possible to modify human behaviour—by offering rewards, by making threats, through education programmes, or using propaganda.

Civilized societies spend a great deal of energy on making people behave themselves despite their natures. The law, the police, schools, and churches all play a part in modifying human behaviour in the domestic environment. The possibility of modifying state behaviour is also widely recognized. Diplomacy, force, trade, aid, and propaganda are all instruments used by leaders to affect the behaviour of the states they are dealing with. Deterrent strategists, for example, argue that even if human nature is fatally flawed (and most of them think it is), states can still be deterred from aggression by the threat of unacceptable punishment in much the same way that many potential criminals can be deterred from robbing banks by the threat of imprisonment (see Chapter 12).

Difficulties in Studying War

No clear authoritative answer has emerged, and perhaps one never will, to the question ‘Why war?’ One of the reasons for this is that the word ‘war’ is a blanket term used to describe diverse activities. There are total wars and limited wars, regional wars and world wars, conventional wars and nuclear wars, high-technology wars and low-technology wars, inter-state wars and civil wars, insurgency wars and ethnic wars. In recent years, wars have also been fought by coalitions on behalf of the international community. It would be very surprising if these widely different activities—linked only by the fact that they involve organized military violence—could be explained in the same way.

Another reason for the absence of an authoritative answer is that the question ‘What are the causes of war?’ is a complicated, ‘cluster’ question. Under its umbrella, as Hidemi p. 75Suganami has pointed out, we may be asking a number of different questions. We may, for example, be asking ‘What are the conditions that must be present for wars to occur?’ or we may be asking ‘Under what circumstances have wars occurred most frequently?’ or we may be asking about how a particular war came about (Suganami 1996: 4). Lumping these questions together inevitably leads to complicated and unsatisfactory answers.

An additional reason for complex answers to the question of war causation is that the concept of causation itself is fraught with philosophical difficulties. One may note that X is often a prelude to Y, but that is not at all the same as proving that X caused Y. Various writers, for example, noting that wars are often preceded by arms races between the belligerents, have claimed that arms races cause wars. Arms races sometimes cause war, but an automatic connection has not been conclusively demonstrated. Arguably, human beings do not fight because they have weapons; they acquire weapons because they already wish to fight. Further, it is worth pointing out that not all arms races have led to war. Anglo-French naval competition in the nineteenth century led to the entente cordiale, while the cold war arms race between the United States and the Soviet Union led to a deterrent stalemate and one of the most prolonged periods of peace in European history.

Given the difficulties inherent in the problem of causation, some writers (particularly historians) have preferred to talk about the ‘origins’ of wars rather than ‘causes’. They believe that the best way of explaining why wars occur is to describe how they come about in terms of the social context and events from which they spring. Thus, if we are investigating the causes of the Second World War, we need to look at the Treaty of Versailles, the world depression, the rise of Hitler, German rearmament, the foreign policies of Britain and France, etc. When we have done this, we are well on the way to understanding the circumstances that led to the Second World War. Those who emphasize the origins of wars hold the view that telling the story of how they come about is as close as we can get to understanding why.

Historians who favour this very specific ‘case study’ approach to the identification of the causes of war tend to believe that since every war is a unique event with unique causes, the causes of war are as numerous as the number of wars. Hence, providing an authoritative answer to the question ‘What are the causes of war?’ would involve a detailed examination of every war that has ever occurred: the uniqueness of every war means that there is nothing general to be said about them. For investigations concerned with the causes of individual wars this is a fair point. Nevertheless, while acknowledging the uniqueness of individual wars, most political scientists see merit in shifting the level of analysis from the particular to the general so that we can see patterns and similarities between the causes of one war and another. At this more general level of analysis we may identify some causes which are common to many, if not all, wars.

Key Points

The idea that war is endemic in the human condition is psychologically unpalatable, but it may nevertheless be true. Even if human nature cannot be changed, it may be possible to modify human behaviour so that wars are less frequent.

Since there are many different kinds of war, it is not surprising that no single cause of war can be identified.

p. 76Human Nature Explanations of War

There is widespread agreement that one of the things that distinguishes human beings from animals is that most of their behaviour is learned rather than instinctive. No one knows what the relative percentages are and there is an ongoing debate about the relative importance of ‘nature’ versus ‘nurture’ (heredity versus environment) as a determinant of human behaviour. Inevitably, this debate has raised the question of whether war is an example of innate or learned behaviour. If it is innate then we must accept it, since in any reasonable timescale biological evolution is too slow to modify it. If it is learned, however, then it can be unlearned and there is hope for us all. Liberal thinkers prefer to emphasize the importance of nurture and are naturally attracted to the idea that aggression and war can be tamed. Conservative thinkers tend to throw their weight behind nature and are therefore sceptical about the possibilities of ridding the world of war.

Though they are disposed to minimize its significance, even committed liberals admit that there is a genetic, instinctive element in human behaviour. We do not start with clean slates on which life’s experiences are written to make us what we are. We come with genetic baggage, biologically programmed, with built-in drives and instincts, one of which, it is argued, is a predilection for aggression and violence. In a celebrated exchange of letters in 1932, both Albert Einstein and Sigmund Freud agreed that the roots of war were to be found in an elemental instinct for aggression and destruction. Einstein thought that ‘man has in him an active instinct for hatred and destruction’, and Freud believed he had identified a ‘death instinct’ which manifested itself in homicide and suicide (Freud 1932). In the 1960s, ethological and socio-biological research brought new life to ‘instinct’ theories of aggression. Konrad Lorenz argued, largely on the basis of his observations of the behaviour of birds and fish, that an aggressive instinct is embedded in the genetic make-up of all animals (including man), and that this instinct has been a prerequisite for survival (Lorenz 1976). Robert Ardrey, in The Territorial Imperative, reached a similar conclusion and suggested a ‘territorial’ instinct to run alongside Lorenz’s four instincts—hunger, fear, sex, and aggression (Ardrey 1966). Edward O. Wilson in On Human Nature noted that human beings are disposed to react with unreasoning hatred to perceived threats to their safety and possessions, and he argued that ‘we tend to fear deeply the actions of strangers and to solve conflict by aggression’ (Wilson 1978: 119).

Although Richard Dawkins in his book The Selfish Gene has shifted the level of analysis from the individual to the genes that help make him what he is, he too is under no illusions about human nature. His argument is that

a predominant quality to be expected in a successful gene is ruthless selfishness. This gene selfishness will usually give rise to selfishness in individual behaviour … Much as we might wish to believe otherwise, universal love and welfare of the species as a whole are concepts which simply do not make evolutionary sense.

Dawkins (1976: 2–3)

This analysis leads Dawkins to the bleak conclusion that ‘if you wish … to build a society in which individuals cooperate generously and unselfishly towards a common good, you can expect little help from biological nature’ (1976: 3) (see Box 5.1).p. 77

5.1Box Key Perspectives

The Causes of War

One may seek in political philosophy answers to the question: ‘Where are the major causes of war to be found?’ The answers are bewildering in their variety and in their contradictory qualities. To make this variety manageable, the answers can be ordered under the following three headings: within man, within the structure of separate states, within the state system.

There is deceit and cunning and from these wars arise.

Waltz, Man, the State, and War

Whatever can be said in favour of a balance of power can be said only because we are wicked.


It is quite true that it would be much better for all men to remain always at peace. But so long as there is no security for this, everyone having no guarantee that he can avoid war, is anxious to begin it at the moment which suits his own interest and so forestall a neighbour, who would not fail to forestall the attack in his turn at any moment favourable to himself.

Woodrow Wilson

Force is a means of achieving the external ends of states because there exists no consistent, reliable process of reconciling the conflicts of interest that inevitably arise among similar units in a condition of anarchy.


The human nature explanation of war is a persuasive one, but at least two qualifications need to be made about it. First, we need to ask whether the evidence produced by the study of animals is really relevant to the behaviour of human beings. The animal behaviourists say it is, because man is simply a higher animal, connected to the rest of the animal kingdom by evolution. To deny that human beings have instincts in the same way that animals do is to deny the almost universally accepted principle of evolution, which links all life on the planet. Even so, we cannot help wondering whether the kind of cross-species generalization engaged in by biologists is valid. After all, human beings are very different from animals. They are more intelligent. They have a moral sense. They reflect about what they do; they plan ahead. Some would claim that these differences are so important that for all intents and purposes they lift man out of the animal world and reduce his instincts to no more than vestigial significance. Waltz notes in his book Man, the State, and War that arguing that human nature causes war is not very helpful since if human nature causes war then, logically, it also causes everything else that human beings do. In his words, ‘human nature may in some sense have been the cause of war in 1914, but by the same token it was the cause of peace in 1910’ (Waltz 1959: 28). In other words, human nature is a constant and cannot explain the wide variety of activities that humans exhibit.

Frustration Explanations of War

Social psychologists, while still locating war in ‘man’, offer explanations for its occurrence that rely less on instinct and more on socially programmed human behaviour. Typically, they p. 78argue that aggression is a result of frustration. When individuals find themselves thwarted in the achievement of their desires, goals, and objectives, they experience frustration which causes pent-up resentment that needs to find an outlet. This frequently takes the form of aggressive behaviour which, in turn, has a cathartic effect of releasing tension and making those who engage in it feel better. Usually aggression is levelled at those who cause the frustration, but sometimes it is vented against innocents who become scapegoats. This psychological process of transferring aggression to a secondary group is called ‘displacement’. Sometimes individuals project their frustrated desires and ambitions onto the group or collective, be it tribe or state, to which they belong. In the words of Reinhold Niebuhr, ‘the man in the street, with his lust for power and prestige thwarted by his own limitations and the necessities of social life, projects his ego upon his nation and indulges his anarchic lusts vicariously’ (1932: 93).

There is a sense in which the ‘frustration/aggression’ hypothesis, which emphasizes the connection between violence and the failure of human beings to achieve their objectives, is somewhat more optimistic than instinct theories of aggression. Although frustration in life is unavoidable, it may be possible either to channel aggression into harmless activities like sport (psychologists call this sublimation), or to organize society in ways that minimize frustrations (sociologists call this social engineering).

Misperception Explanations of War

Accepting that wars cannot occur unless statesmen decide to wage them, many believe that decisions to go to war are often the result of misperception, misunderstanding, miscalculation, and errors of judgement. Essentially, those who think in this way regard wars as mistakes, the tragic consequences of failing to appreciate things as they are. This being the case, they are caused more by human frailty or fallibility than malice. Robert Jervis (1976), building on the ideas of Kenneth Boulding (1956), has contributed enormously to our understanding of these psychological causes of war. He makes the point that in order to make sense of the world around us, all of us develop images of reality through which we filter the welter of information that bombards our senses. These ‘images’ of reality are more important than reality itself when it comes to determining our behaviour; they act as a distorting lens which inhibits our ability to see reality as it is and predisposes us to judge the world in ways that confirm our preexisting concepts.

Critically important misperceptions likely to lead to war include mistaken estimates of both enemy intentions and capabilities, inaccurate assessments of the military balance between adversaries, and failures to judge the risks and consequences of war properly. Quite frequently these kinds of misperceptions are made by both sides involved in a conflict. For example, Greg Cashman has argued that in the Gulf War, Saddam Hussein may have perceived a threat from Kuwait’s reluctance to allow Iraq to cancel its debts and its unwillingness to pump less oil. He may even have perceived a joint American–Israeli–British conspiracy to deny Iraq sophisticated weaponry. On the other hand, leaders in virtually all of the Middle East capitals underestimated the degree of threat posed by Iraq and were taken by surprise when Kuwait was invaded. Thus, while Iraqi leaders overestimated the degree of threat to their interests, their opponents underestimated the hostility of Iraq (Cashman 1993: 63). But perhaps the most critical misperception of all was Saddam Hussein’s failure to anticipate p. 79Western resolve and the creation of a powerful military coalition against him. There were at least as many misperceptions surrounding the 2003 Iraq War. Despite the unambiguous warnings he had received, Saddam was convinced that the United States and Britain would not invade. For their part, the Americans and the British believed that Saddam possessed weapons of mass destruction and was well on the way to acquiring nuclear capability. They also believed that invasion would be universally welcomed by Iraqis, that Iraq was a haven for terrorists, and that democracy could be created with relative ease. None of these beliefs were true, but for the participants they formed the psychological reality against which they made their decisions.

Before the Second World War, Hitler mistakenly believed that Britain would not fight and Chamberlain mistakenly believed that Germany could be appeased by concessions. Other delusions and misconceptions that contributed to the outbreak of war in 1939 have been identified by A. J. P. Taylor. Mussolini was deluded about the strength of Italy; the French believed that France was impregnable. Churchill believed that Britain could remain a great power despite the war, and Hitler ‘supposed that Germany would contend with Soviet Russia and the United States for mastery of the world’ (Nelson and Olin 1979: 153–4). In Britain hardly anyone expected that German blitzkrieg tactics would bring France down in a matter of weeks, and throughout Europe people grossly overestimated the power of strategic bombing. Given this plethora of misunderstandings, misjudgements, and misperceptions, it is easy to argue that statesmen stumbled into the Second World War because they were out of touch with reality.

Much the same point can be made about the Falklands War in 1981. Misperceptions abounded. Britain seriously misinterpreted Argentine intentions with respect to invasion, and Argentina badly misjudged Britain’s determination to resist. For years the two governments had been involved in intermittent negotiations about a possible transfer of sovereignty, and, though little progress had been made, the Conservative government could not believe that the Argentine junta would seize South Georgia before the possibilities of negotiation had been exhausted. What the British government failed to appreciate was the significance of the Malvinas in the Argentine psyche and the domestic pressures to act that this put on President Galtieri and Dr Costa Mendez. For its part, the government of Argentina could not believe that at the end of the twentieth century a Eurocentric, postcolonial Britain was prepared to spill blood for the sake of a barren relic of empire 10,000 miles away.

There is a sense in which the misconceptions prevalent both in Germany before the Second World War and in Argentina before the Falklands War are understandable. The signals transmitted by the policy of appeasement may have suggested to Hitler that since he had got away with swallowing the Rhineland in 1936, and Austria and the Sudetenland in 1938, he could probably get away with aggression against Poland in 1939. In the case of the Falklands, the casual pace of British diplomacy and the absence of any serious military capability in the area may have suggested to the Argentines that Britain was not much interested in the fate of the Falkland Islands and was unlikely to defend them. Perhaps, in both of these cases, it was not so much that signals were misread but that the wrong signals were sent. Either way, Britain’s enemies made serious miscalculations of her intentions, and war resulted.

If wars are caused by misperceptions and misunderstandings created by cognitive biases, then conditions for peace include more clear thinking, better communications among p. 80countries, and education. This thought lies behind the United Nations Educational, Scientific, and Cultural Organization (UNESCO) motto ‘Peace Through Understanding’, various ‘education for peace’ proposals, and the attempts that are frequently made to get potential adversaries around the conference table so that they can better understand each other. The basic idea is that if enemies can be brought to appreciate each other’s perspectives, then the disputes that divide them will dissolve because they will be seen to be either illusory or not sufficiently serious to justify war. Perhaps we can detect in this approach relics of the idea of a natural ‘harmony of interests’, which would prevail if only misunderstandings were cleared up.

Before we are persuaded by this idea that wars can be prevented by removing misperceptions and misunderstandings, a word of warning is appropriate. It may not be possible to eradicate misperception from human affairs given the inherent cognitive weaknesses of the human mind. The need to simplify, the inability to empathize, the tendency to ethnocentrism, the reluctance to relinquish or recognize prejudices—all familiar human weaknesses—may make some degree of misperception inevitable. Herbert Butterfield recognized this point when he identified an ‘irreducible dilemma’ lying in the very geometry of human conflict. Butterfield imagined a situation in which two potential enemies, both armed, face each other. Neither harbours any hostile intent but neither can be sure of the intentions of the other.

You cannot enter into the other man’s counterfear [and] it is never possible for you to realize or remember properly that since he cannot see the inside of your mind, he can never have the same assurance of your intentions that you have.

Butterfield (1952: 21)

Butterfield makes the point that the greatest war in history could be caused by statesmen who desperately want peace but whose cognitive limitations lead them to misinterpret each other’s intentions (Butterfield 1952: 19). (Discerning students will realize that Butterfield’s ‘ultimate predicament’ has, in recent years, surfaced in the literature of strategic studies as ‘the security dilemma’.)

Additionally, not all wars are caused by misperceptions and misunderstandings, even though they may be surrounded by them. Some wars—perhaps most—are rooted in genuine disagreement and conflicting interests, and in these cases discussions between enemies simply promote a better understanding of the disputes that divide them. Indeed, in some situations improved understanding may actually exacerbate the divisions between adversaries. When it was suggested to him that international hatred and suspicion could be reduced by getting nations to understand one another better, Sir Evelyn Baring, British governor in Egypt between 1883 and 1907, replied that ‘the more they understand one another the more they will hate one another’ (Waltz 1959: 50). Perhaps it can be argued that for most of the 1930s Britain was at peace with Germany precisely because the British did not understand Hitler. When, in September 1939, the penny finally dropped, Britain declared war on Germany.

Group Explanations of War

Though embarked on by individual human beings, war, by definition, is a group activity. It is waged by human collectives—factions, tribes, nations, states, and even perhaps by p. 81‘civilizations’. This has led some to shift the responsibility for war from human beings to the group within which they live and to which they owe varying degrees of allegiance. Those who argue in this way believe that there is nothing much wrong with human beings per se, but that they are corrupted by the social structures in which they live. In the words of Friedrich Nietzsche, ‘Madness is the exception in individuals but the rule in groups’ (Nietzsche 1966: 15). Essentially, the argument is that there is something about human collectives that encourages violence.

Perhaps the trouble starts with the sense of difference that we all feel between ‘us’ and ‘them’. Whenever people can make a distinction between those who belong to their own collective grouping—be it tribe, state, or nation—and other groups with which they cannot identify easily, they have laid the foundation for conflict. It is all too easy for a group to slide from recognizing that it is different from other groups to believing that it is superior to them. Hence, this sense of differentiation readily leads to group selfishness, inter-group conflict, and ultimately war. As Niebuhr once observed, ‘altruistic passion is sluiced into the reservoirs of nationalism with great ease, and made to flow beyond them with great difficulty’ (Niebuhr 1932: 91).

G. Le Bon was one of the earliest social psychologists to notice that the behaviour of social groups is different from—and usually worse than—the behaviour of the individuals that comprise them. He developed the idea of crowd psychology: that in a crowd a new entity or collective mind comes into being. He believed that while in groups, individuals lose their normal restraints, become more suggestible, more emotional, and less rational. What is more, groups have reduced feelings of responsibility, because the more responsibility is diffused in crowds, the less heavily it weighs on each individual. Since responsibility is everywhere (and therefore nowhere), blame cannot be allocated specifically, and this frees human collectives from normal moral restraints (Le Bon 1897: 41). This thought was neatly captured in the title of Niebuhr’s classic Moral Man and Immoral Society. Eric Hoffer, in discussing the appeal of mass movements, makes the same point very graphically: ‘When we lose our individual independence in the corporateness of a mass movement, we find a new freedom—freedom to hate, bully, lie, torture, murder and betray without shame or remorse’ (Hoffer 1952: 118).

Human beings have always lived in differentiated groups and it is unlikely that this will change in the foreseeable future. The interesting question is whether some groups are more war prone than others. In the context of inter-state wars, for example, are capitalist states more warlike than socialist states or vice versa? There is no clear answer to that question. Can we argue that democratic states are more peace-loving than authoritarian states? Again there is no clear answer. Although some evidence suggests that democracies do not fight each other very often, other historical evidence suggests that democracies fight just as often as other types of states. As the wars in Iraq and Afghanistan (as well as the struggle against ISIS) have shown, democratic states have also demonstrated some enthusiasm for wars of intervention in support of human rights. This current fashion for waging wars in support of liberal values does not augur well for a peaceful world.

Various observers have noted, however, that democracies seldom, if ever, fight each other. Michael Doyle, for example, has argued that liberal states are more peacefully inclined towards each other because their governments are more constrained by democratic institutions, and p. 82because they share the same democratic values. Commercial interdependence between liberal states also gives them a vested interest in peace (Doyle 1983, 1986). If Doyle and those who share his views are right, one of the conditions for peace is the spread of democracy—a trend that has gathered pace particularly since the end of the cold war. For the first time ever, almost half of the world’s governments are now democratic. The thesis that the spread of democracy will promote peace is no more than plausible, however, and it would be unwise to accept it uncritically.

The Bargaining Model and the Causes of War

In contrast to social and psychological-based theories which argue that war is caused by social factors, miscalculation, or perceptual biases, the bargaining model of war sees war as a deliberate political act. Following the Clausewitzian tradition that war is a means of achieving political objectives and is not an end in itself, bargaining theorists argue that conflicts arise as a result of disagreements over scarce resources or policy choices. They argue that because war is costly, potential belligerents would prefer to reach a settlement rather than fight. However, according to the bargaining model: ‘Fighting breaks out when two sides cannot reach a bargain that both prefer to war. Each side fights to improve its chances of getting a desirable settlement of the disputed issue. The war ends when the two sides strike a bargain that both prefer to continuing the war … the duration of peace following the war reflects the willingness of both sides not to break the war-ending bargain’ (Reiter 2003: 29).

One bargaining theorist, James Fearon, argues that the failure to reach a bargain, resulting in the outbreak of a violent conflict, may be the result of three things: uncertainty, commitment issues, or indivisibility problems. Uncertainty arises when one side either overestimates its own capabilities or underestimates the strength or resolve of its opponent. One example would be Hitler’s attack on Russia in the summer of 1941. A second reason why wars break out is the inability of potentially hostile actors to commit that they will not use their military strength in the future. If one side sees an advantage in striking first it may engage in a pre-emptive attack before its advantage disappears. The lack of commitment to a first strike may prevent a bargain being reached which would have prevented the conflict. Fearon’s third explanation for the outbreak of war focuses on the indivisibility of some issues which are in dispute. This is sometimes the case in ethnic disputes within states. Conflicts can break out if a particular ethnic group seeks to achieve autonomy or independence by violent means. This is often seen as setting a precedent which results in a violent response by the state.

One contemporary illustration of the bargaining model is the conflict between the United States under Donald Trump and North Korea. Both sides have been engaged in brinkmanship, threatening pre-emptive strikes to achieve their respective political objectives: the US to stop the North Korean nuclear programme and North Korea for deterrence reasons and to promote its status. The strategy of brinkmanship is, in essence, part of the bargaining process. The threats of pre-emption are the result of the failure of previous attempts to arrive at a mutually acceptable solution. Such threats could also result in conflict, with wider regional repercussions. As is often the case between hostile actors, arriving at a bargain which will suit both sides remains extremely difficult. It remains to be seen whether a bargain can be struck between the US and Kim Jong-un.p. 83

Key Points

Some believe that human beings are genetically programmed towards violence, but there is an ongoing debate about whether war is an example of innate or learned behaviour.

Social psychologists have argued that aggression is the result of frustration. Some believe feelings of aggression can be channelled into harmless activities like sport.

Wars that result from misperceptions, misunderstandings, and miscalculations by statesmen might be prevented by better communications and more accurate information.

Some believe that there is something about human collectives that encourages violence.

There is some evidence, however, that though democratic states fight as frequently as other states, they do not fight each other.

Bargaining theorists of war focus on political causes such as uncertainty, commitment issues, and the indivisibility of some issues in dispute.

Wars ‘Within’ and ‘Beyond’ States

Perhaps because of the spread of democracy, it is often argued that inter-state violence is now less of a problem than it was just a few years ago. Indeed, it has been calculated that since 1970 fewer than 10 per cent of armed conflicts have been inter-state wars fought for traditional objectives. Sometimes, of course, wars straddle both the ‘internal’ and ‘inter-state’ categories. The Indo-China war is a case in point. What started as a colonial war developed into a civil war and became an inter-state war with the intervention of the United States and its allies in Vietnam. In Libya in 2011 resistance to Colonel Gaddafi, triggered by ‘the Arab Spring’, also led to Western intervention in support of the rebels. The subsequent overthrow of Gaddafi meant that the distinction between civil conflict and inter-state conflict was blurred.

One reason why it is argued that inter-state wars may be going out of fashion is that in a globalized world the expected value of conquest has diminished and its costs, both economic and political, have escalated. States bent on improving their standards of living are better advised to spend their money on education, research, and technology than on conquering other countries and trying to hold down hostile populations. The contemporary moral climate makes aggressive wars difficult to justify, and the media revolution makes it difficult to avoid the opprobrium attached to waging them.

General Sir Rupert Smith is one of the most recent in a long line of commentators who echo this fashionable perception that old-fashioned wars are old hat. Violence exists, he says, but ‘wars in the future will not be waged between states. Instead we will fight among the people’ (Smith 2006: 1). The general may be right, but a little reflection suggests that both he and those who think like him may be premature in their judgement. The conflicts between Israel and Hizbullah in Lebanon in 2006, Russia and Georgia in 2008, Israel and Hamas in Gaza in 2008 and 2014, and Russia and Ukraine over the Crimea in 2014, all took place across neighbouring borders. Levy and Thompson have argued that inter-state wars are normally much more significant in their consequences than intra-state conflicts (Levy and Thompson 2010). It is also possible to envisage a scenario, perhaps not far into the future, when there is p. 84a desperate scramble for scarce resources by capitalist countries that find it increasingly difficult to sustain their profligate lifestyles as vital minerals, particularly fossil fuels, start to run out.

If that should happen, advanced industrial countries might face the stark choice between going under or waging inter-state war to secure supplies of essential materials. Take oil for example. To deny a modern industrial state oil is to deny it the means of survival. Since no state has ever committed suicide, who can doubt that, faced with the destruction of their way of life, states will do whatever is necessary to secure adequate supplies of oil—including waging inter-state war. In short, inter-state war is not yet off the agenda, even for civilized states that pride themselves on their peaceful intentions.

Even if it is accepted that there has been a decline in inter-state wars, this does not explain the rising incidence of internal war. There are a number of reasons why civil wars have become common, but perhaps the most basic is that in many parts of the world sovereign states—which are usually defined in terms of the monopoly of military power that they wield within their territory—have lost that monopoly to a variety of bodies, be they tribes, ethnic groups, terrorists, warlords, splinter groups, or armed gangs. As the conflict in Syria demonstrates, when governments lose their monopoly of military force they can no longer control their territory or their people. The domestic environment begins to resemble the ungoverned international system which, as we saw earlier in this chapter, is a structural, ‘permissive’ cause of war. In Hobbesian anarchy, ancient tensions and hatreds that were previously contained burst to the surface. We have also seen the consequences of this in Bosnia, Kosovo, Chechnya, Afghanistan, Sierra Leone, Somalia, East Timor, and Haiti.

What is particularly horrifying about ethnic wars is that people are brutalized and killed not because of anything they have done, not even because of their politics, but simply because of who they are. That is what is so terrible about the persecution of the Tutsis in Rwanda, the Tamils in Sri Lanka, the Kurds in Iraq, the Muslims in Bosnia, and the Albanians in Kosovo. Ethnic wars are quite different from Clausewitzian politically motivated conflicts where the belligerents disagree about something and seek to resolve their disagreement by inter-state war—an activity conducted according to moral and legal rules. It may be going too far to describe run-of-the-mill inter-state wars as rational and civilized, but there is a grain of sense in the thought. Ethnic wars are quite different. They are not about the pursuit of interests as normally understood. They are about malevolence and they are not restrained by any legal or moral rules. As the rise of Islamic State in Iraq and Syria (ISIS) in 2014 demonstrates, ‘religious’ or ‘ethnic cleansing’, like ‘the final solution’, is surely one of the most sinister phrases to enter the political vocabulary of the twentieth and twenty-first centuries.

It is ironic that authoritarian governments, so frequently blamed for inter-state wars, were instrumental in preventing civil wars in countries like Yugoslavia and the Soviet Union. Hobbes’ Leviathan may have its attractions if the alternative is genocidal violence. If the thousands of ethnic groups that exist in the world can no longer be contained in nation states, then we face the break-up of international society into a myriad of micro-groups. The consequences of ‘Balkanization’ on this scale are unlikely to lead to a more peaceful world. But is it possible to generalize about the origins of civil conflicts?

There is a significant and interesting literature about the causes of civil wars. One of the liveliest areas of scholarship is the ‘greed versus grievance debate’. Paul Collier and Anke Hoeffler wrote an important piece in 2000 which argued that ‘greed’ was much more important than p. 85‘grievance’ in understanding why civil wars began and why they often lasted for considerable periods of time. Focusing on an economic explanation of causes, they argued that those involved in armed conflicts were largely motivated by a desire to improve their own financial situation (i.e. ‘greed’), rather than by ‘grievances’ related to issues of identity, such as ethnicity, religion, or social class. Civil wars, they argued, were more likely to occur where there were lootable natural resources such as diamonds, drugs, or timber. The examples often cited to justify this theory include the role of diamonds in the conflicts in Sierra Leone, Angola, and the Democratic Republic of Congo, timber in Cambodia, and the poppy trade controlled by the insurgents in the conflict in Afghanistan. According to this view, rebels often have an incentive to keep civil wars going to improve their own or the group’s financial position.

Those who reject the ‘greed thesis’ do so either because they believe that ‘grievances’ relating to such things as oppression, inequality, or discrimination are at the root of civil wars or because they believe that civil conflicts are much more complex than the ‘greed versus grievance theory’ suggests. ‘Greed’ and ‘grievance’ may be interrelated or other factors may be involved. David Keen, in his study of ‘Complex Emergencies’, argues that it is important to look at the ‘specifics’ of particular conflicts. Different types of conflicts have different causes and this requires a mix of multiple theories to understand their causes. (See Critical Thinking.)

Critical Thinking

‘Greed’ is more important than ‘grievance’ as a cause of civil wars


The importance of economic forces. ‘Ethnic tensions and ancient political feuds are not starting civil wars around the world—economic forces such as entrenched poverty and the trade in natural resources are the true culprits.’ (Collier 2004: 4)

The key role of lootable resources. ‘Greed’ in terms of lootable diamonds, timber, and drugs were the critical factors in the conflicts in Angola, Nigeria, Democratic Republic of Congo, Cambodia, Liberia, and Sierra Leone.

The importance of the ‘Resource Curse’. At the heart of civil conflicts is the ‘Resource Curse’—i.e. the richer a country is in natural resources, the more likely it is to suffer civil violence.

Greed is the key. ‘Grievance discourse is merely window dressing.’


The roles of poverty and justice. While greed may be present, relative deprivation and the search for social justice are more often at the heart of civil wars.

Libya as a case study. Libya, with the fall of Gaddafi, does not conform to the idea of a greed-based rebellion. Several grievances such as vertical inequalities, involving economic grievances and a lack of political rights, as well as horizontal inequalities, involving regional and tribal differences, were the main motivation for the conflict.

The role of corruption and ethnicity. Ukraine provides a good example of the role that grievances relating to corruption and ethnicity play in civil conflicts.

p. 86 Religion as a cause. Grievances associated with religion are often a fundamental cause of civil conflict. Iraq and Syria provide compelling evidence of this.



Do you agree that ‘greed’ is the main cause of civil wars?


How important do you think the perception of relative deprivation is as a cause of civil violence?


What have been the main causes of civil violence in Syria?

Key Points

As inter-state war has waned, intra-state conflict has become more frequent.

Ethnic conflicts do not easily fit the Clausewitzian model. They are particularly violent and people are often killed because of who they are rather than because of their behaviour or politics.

There is a major debate between those who believe that ‘greed’ or ‘grievance’ are the main causes of civil wars.


There is no shortage of ‘cures’ for the ‘disease’ of war. Some are bizarre. For example, Linus Pauling once suggested that wars are caused by a vitamin deficiency and that we could eat our way out of aggression by swallowing the appropriate tablets. Others—like calls to change human nature, to reconstruct the state system, to redistribute equitably the world’s wealth, to abolish armaments, or to ‘re-educate’ mankind—follow with faultless logic from the various causes of war which scholars have identified. But since there is no prospect of implementing them in the foreseeable future, in a sense they are not solutions at all. Henry IV’s reputed comment on an equally impractical proposal for peace is still appropriate: ‘It is perfect’, the king said, ‘Perfect. I see no single flaw in it save one, namely, that no earthly prince would ever agree to it.’ Hedley Bull has rightly condemned such solutions as ‘a corruption of thinking about international relations and a distraction from its proper concerns’ (Bull 1961: 26–7).

We have to begin by recognizing the limits of what is possible. Maybe we can then edge our way forward by improving our techniques of diplomacy, communication, crisis avoidance, and crisis management; by developing a concept of enlightened self-interest which is sensitive to the interests of others; by extending the scope of international law and building on existing moral constraints; by learning how to manage military power through responsible civil–military relations and sophisticated measures of arms control; and by strengthening cooperation through international organizations and world trade. These are not spectacular, radical, or foolproof solutions to the problem of war. That is why practical foreign policymaking is more akin to weeding than landscape gardening. However, they are practical steps p. 87that offer the possibility at least of reducing its frequency, and perhaps also of limiting its destructiveness. Even if war could be abolished, we need to remember that peace is not a panacea in which all human antagonisms are resolved. Peace is simply the absence of war, not the absence of conflict. As the cold war demonstrated, it is just as possible to wage peace as it is to wage war. Though ‘peace’ and ‘war’ are usually regarded as opposites, there is a sense in which both are aspects of the conflict that is endemic in all social life. War is simply a special kind of conflict that differs from peace only by its violent nature. The fact that peace is not a panacea explains why, when confronted with the stark choice of peace or war, leaders sometimes choose war. Some kinds of peace—under dictatorships, for example—may be worse than some kinds of war. In other words, although almost everyone wants peace, almost no one (apart from strict pacifists) wants only peace or peace at any price. If it were otherwise, the problem of war would disappear since as a last resort states can always avoid war by surrendering. Capitulation might bring peace, but it would almost certainly entail the loss of some of those other things that states want—like independence, justice, prosperity, and freedom. When it comes to the crunch, leaders may think that some fundamental values or goals are worth fighting for.

Ideally, of course, what people want is a world-wide just peace. Unfortunately, this is an unattainable dream. It would require agreement on whose justice is to prevail. It would require a redistribution of the world’s wealth from the haves to the have-nots. Just peace would require all religious and political movements—Muslims, Christians, Jews, Hindus, communists, capitalists—to tolerate each other. It would also require an end to cultural imperialism and an agreement that differing cultural values are equally valid. It would probably require the disappearance of borders and differentiated societies with their ‘them’ and ‘us’ mentalities. In short, it would require human beings to behave in ways in which they have never behaved. Since justice and peace do not go together, statesmen will have to continue choosing between them. The pursuit of justice may require them to wage war, and the pursuit of peace may require them to put up with injustice. During the cold war years, Western politicians, by abandoning Eastern Europe to its fate under communism, thought, probably rightly, that peace was more important than justice. Since the end of the cold war, they have tended to put justice before peace—witness the upsurge of violence caused by wars of intervention in support of human rights and democratic values. The critical question now is whether, in juggling the priorities of peace and justice, we have got the balance right, or whether our current enthusiasm for Western values and human rights implies an ever so slightly casual attitude to the problem of war. Perhaps, in the interests of peace, there is something to be said for the realist policy of fighting necessary rather than just wars.



Are the causes of war unique in each case or is it possible to find similarities and patterns in the causes of war in general?


Do you think the spread of democracy will solve the problem of war?


To which would you allocate priority: the pursuit of peace or the pursuit of justice?


Is aggressive behaviour instinctive or learned?


How convincing is the argument that wars are a result of misjudgement and misperceptions?


Is war inevitable?


p. 88 Is war an instrument of policy or an outburst of irrationality?


Are inter-state wars going out of fashion?


If international order rests on the principle of ‘non-intervention’, using Libya or Syria as an example, how can military intervention in the internal affairs of sovereign states be justified?


Can the problem of war be solved through education?

Further Reading

J. S. Levy and W. R. Thompson, The Causes of War (Chichester: Wiley-Blackwell, 2010)Find it in your libraryGoogle PreviewWorldCat provides a comprehensive analysis of the leading theories on both inter-state and civil wars.

R. Niebuhr, Moral Man and Immoral Society: A Study in Ethics and Politics (New York and London: Charles Scribner’s Sons, 1932)Find it in your libraryGoogle PreviewWorldCat is one of the best studies of ethics and conflict.

E. Nietzsche, The Philosophy of Nietzsche (New York: New American Library, 1966)Find it in your libraryGoogle PreviewWorldCat is a useful source for Nietzsche’s views.

S. P. Rosen, War and Human Nature (Princeton, NJ: Princeton University Press, 2005)Find it in your libraryGoogle PreviewWorldCat gives an analysis of the contribution that neuroscientific and biological research can make to the study of war.

S. Van Evera, The Causes of War (Ithaca, NY: Cornell University Press, 2009)Find it in your libraryGoogle PreviewWorldCat provides an up-to-date analysis of the causes of war.

K. Waltz, Man, the State, and War (New York: Columbia University Press, 1959)Find it in your libraryGoogle PreviewWorldCat is one of the best studies of the causes of war.

Web Links

See for Paul Collier and Anke Hoeffler’s views on ‘greed’ versus ‘grievance’ as a cause of civil war.

David Keen also looks at the links between ‘greed’ and ‘grievance’ in civil war in

Robert A. Hinde, The Psychological Bases of War at is another useful source on the psychological causes of war.

© Oxford University Press 2019