Is there a Primary Cause to War?

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This response to the proposition shall focus upon four broad areas within the causes of war. Firstly, it will be necessary to speak of necessary causes of war, as these feature heavily in the literature on war causation. The discussion will then move on to questioning whether or not it is simply human nature that yearns to constantly fight aggressive wars. Then it shall be necessary to address those permissive cause of war which is a notable feature of the world in which we live, before finally outlining the different forms of misperception that are often a crucial instigator for war. No doubt many causes in the discussion will be ignored, but this is merely indicative of the fact that the causes of war are so widespread and so numerous. Hence, my argument throughout this discussion shall attempt to show that there are many causes of war, and that it is troublesome to think in terms of a primary cause of war.

Firstly, before the discussion can proceed to any degree, it shall be necessary to outline exactly what war is. A suitable definition of war appears to be that which features “armed conflict between two or more parties, usually fought for political ends” (McLean 1996, p. 521). The first category of causes that is of importance is necessary causes of war, that is a cause “that must be present if war is to occur” (Baylis et al 2002 p. 73). As can be seen from the definition of war above, armaments is an example of a necessary cause of war “because without them no war could be fought” (Ibid). In fact, a further step could be taken to say that not only armaments, but up to date technological equipment has become almost something taken for granted during the wars of the past century. In World War I for example, this meant that technology was needed to aid “lethal firepower (e.g. the machine gun) or greater mobility (e.g. the railroad)” (van Evera 1998, p. 17). Regarding the same war, if many historians are correct in saying that detailed “military mobilisation plans were an important factor” (Levy 1986, p. 193) in the cause of World War I, then such plans were a necessary cause of the war, as without them the war would not have occurred, at least in hindsight. Thus World War I indicates that there can be multiple necessary causes of a war, thus immediately casting doubt upon the notion of a primary cause of war. To approach necessary causes from a further angle it can be suggested that “war is far more likely when conquest is easy” (van Evera 1998, p. 5). Thus the conquest of war will be far easier to achieve if there is no world government to monitor state behaviour, or even one state playing a ““balancing” role” (James 1995, p. 185) in checking the behaviour of other states. Therefore the absence of such actors is really a necessary cause of war. The concept of necessary causes of war has been included not only to signify that there can be many necessary causes of a single war, such as those aforementioned and the simple “expectation of victory” (Levy 1983, p. 84). In fact, its inclusion serves to highlight also that there are several causes of war that are not necessary. A state might desire another’s material resources such as oil, but this is not a necessary cause of war, because war can occur without such desires.

The argument will forthwith move on to examining the somewhat depressing view that war is simply cause by the sum of human instincts and natural reactions. Albert Einstein and Sigmund Freud were among those who subscribed to such an idea that “the roots of war were to be found in an elemental [in humans] instinct for aggression and destruction” (Baylis et al 2002, p. 75). There exists a conviction that this element in humans can be seen in a subsequent human desire to “divide the world between ‘us’ and ‘them’” (Hirshleifer 1998, p. 462). Such a mentality was prevalent in the ruthlessness of “the Moslem conquests starting in the 10th Century” (Ibid). On another level, this natural need or desire for war might originate in leaders from being “thwarted in the achievement of their desires, goals and objectives” (Baylis et al p. 77), or, to put it in a rather hyperbolic manner, the suffering of “domestic repression” (Jervis 1993, p. 245). In practice, this can be seen with former British Prime Minister Margaret Thatcher and the 1982 Falklands War. Although she was not exactly enduring ‘domestic repression’ at the time, her “popularity had been at an all-time low for a serving Prime Minister” (, and what became known as the Falklands Factorwas “crucial to the scale of the Conservative majority in the June 1983 general election” (Ibid). Thus we have a clear, successful instance of domestic problems fuelling a need for war to counter such difficulties, although the aim is not to imply that this was the only reason for Margaret Thatcher to instigate theFalklands conflict. The questioning of why states would “prefer the costly gamble of war to any negotiated settlement” (Fearon 1995, p. 386) is very pertinent. Nevertheless, it can be answered with the idea that nature, in both humans and animals, distrusts ‘“the slow and uncertain determinations’ of reason” (Hirshleifer 1998, p. 462). Hence, human leaders could disregard reason by choosing a costly war over the possibility of negotiation when it is clearly not in their own interests to do so. However, it is difficult to accept that war is simply a result of human nature completely, and Kenneth Waltz had a very valid point when he asserted that human nature “was the cause of peace in 1910” (Baylis et al 2002, p. 76). The basic reasoning here is that if human nature causes war, when peace occurs then equally human nature should be explained as the trigger for that too. If human nature was totally committed to war, then humans would not allow the United Nations to exist, as it would be a potential impediment to a fundamental activity. While human nature may allow irrationality, it is ridiculous to suggest that humans will always behave irrationally. So, although human nature probably causes war in some instances, war will not always follow from pure human nature, therefore the suggestion is that an instinctive human need for war is only one of a number of war causes, and is neither a necessary nor primary cause of war.

Additionally, it shall now be necessary to put forward the importance of permissive causes of war. Permissive causes of war are those “features of the international system which, while not actively promoting war, nevertheless allow it to happen” (Baylis et al 2002, p. 71). The United Nations did not actively suggest the occurrence of the Iraq War of 2003, but they could do nothing to prevent it happening. The fact that wars have been permitted is exemplified by the fact that “aggressive war was not an international crime” (Goodhart 1942, p. 66). The problem of successfully stopping war is highlighted inadvertently by Hitler at the time of the Second World War, for he realised that claiming some French territory would “unite the French people against him in a way that no other threat could do” (Goodhart 1942, p. 75). This displays the fact that the only thing weighing on Hitler’s mind was the French people, any international authority that would attempt to prevent aggressive action such as the League of Nations was clearly not worthy of his respect, for the implication is that they would allow aggressive action if that had been the option he had chosen to pursue. A more indirect example of permitting war is the result of state actions. One such instance is in having rigid, inflexible military plans that “may preclude policymakers from adopting certain alternatives which might conceivably be sufficient to head off an impending war” (Levy 1986, p. 200). Another indirect permission of war is simply the surrounding situation and the aggressive logic it promotes. Kenneth Thompson conceives a situation where a law-abiding citizen is pushed to the front of a railway platform by the sheer numbers of a crowd, but instead of not reacting the citizen “kicks and struggles and fights to stay alive” (Baylis et al 2002, p. 73) because he is “in an environment where he cannot afford to be good” (Ibid). Similarly, in a situation such as the Security Dilemma, where you cannot be sure of your adversaries’ intentions, even normally peaceful states “may feel compelled by the logic of the situation to take actions which they recognise may contribute to war” (Levy 1986, p. 204). Even the theoretically mutually beneficial principle of collective security can exacerbate war. As one time Czechoslovakian Foreign Minister Jiri Dienstbier explained, true collective security agreements involve every party part of the agreement giving “military assistance, in the event of an attack against any participant” (Betts 1992, p. 28). It is not difficult to imagine that the involvement of so many states in a conflict might simply inflame it even more. In short, there are many examples of permissive causes of war, some of which are neither necessary nor have a particular relevance to human nature, cementing the idea that there is not really a single cause of war.

Finally, it would be foolish to ignore the importance misperception plays in activating conflicts. Misperceptions leading to war come in a variety of forms, including “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” (Baylis et al 2002, p. 77). At the most unfortunate level, war can result from misperceptions when both sides ostensibly desire peace. In such a situation, ““the reciprocal fear of surprise attack” (Jervis 1993, p. 242) comes into existence. In such a situation, both sides desire peace, but are not convinced that the other does, so one side might launch an attack so that they are not the victim of an attack they may not be prepared for. The most common form of misperception is indeed exaggerating the hostility of the adversaries’ intentions. In 1914, this was important in the decision made to go to war “by many of the European states, particularly Austria-Hungary” (Jervis 1993, p. 88). A more basic underestimation of opponents has also often triggered war, not least with Germany in both World Wars underestimating “the industrial capacity of the United States” (Levy 1983, p. 83), and numerous other examples involving other states, such as the “Russo Japanese war” (Levy 1983, p. 84). To demonstrate that misperceptions can be more complex, there have been instances where escalation in conflict has resulted from a change in the adversary’s perception of one side’s hostility. In practice, the Korean War saw the United Statesfail to comprehend “China’s perception of the threat imposed by a unified Korean regime associated with the US” (Levy 1983, p. 90). As a consequence of this, the Americans “failed to anticipate the Chinese intervention in response to the crossing of the 38th parallel” (Ibid). In short, the Americans failed to grasp the idea that this conflict would escalate because of how the Chinese perceived their association with the Korean regime. It should also be pointed out that when conflict is rife, it is in states’ advantage to “cloak their foreign and defence policies in greater secrecy” (van Evera 1998, p. 11) as states “compete for information advantage” (Ibid). Just before World War I broke out, it was in the interests of the German Chancellor “to misrepresent the strength and nature of German support forAustria’s plans [to crushSerbia]” (Fearon 1995, p. 398) for fear of making “Germany appear the aggressor” (Ibid). As the Germans were not perceived as aggressive, they were not warned as to their behaviour “until fairly late in the crisis, by which time diplomatic and military actions had made backing off more difficult [for Germany]” (Ibid). It is thus apparent that concealing true information can be a cause of war, albeit an indirect one. This section should have demonstrated not only that misperception has been an important factor in causing war on several occasions, but that misperception manifests itself in a variety of forms.

In conclusion, the overwhelming view here is that there is not a primary cause of war. Necessary causes of war can encompass a wide variety of causes of war from well maintained armaments to a simple psychological expectation of victory. Human nature accounts for some wars but as it also accounts for peace it is not realistic to portray it as a primary cause of war. Permissive causes and causes related to misperception both address vital areas in the academic field of war causation, but these both incorporate many different forms that it is difficult to locate a single cause of war. Misperception, for example can involve both overconfidence of one’s own possibilities and an overestimation of the capabilities of rivals. In short, the causes of war are so varied and so numerous that it is difficult to disagree with the idea that “the search for a single cause appropriate to all wars is futile” (Baylis et al 2002, p. 67).


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2. Betts, R.K. (1992) ‘Shaping the New WorldOrder Systems for Peace or Causes of War? Collective Security, Arms Control and the New Europe’ International Security, 17 (1), 5-43.

3. Fearon, J. (1995) ‘Rationalist Explanations for War’ International Organisation, 49 (3), 379-414.

4. Goodhart, A.L. (1942) ‘International Law and the Causes of War’ Transactions of the Grotius Society, 28, 65-82.

5. Hirshleifer, J. (1998) ‘The Bioeconomic Causes of War’ Managerial and Decision Economics, 19 (7/8), 457-466.

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7. Jervis, R. (1993) ‘Arms Control, Stability, and Causes of War’ Political Science Quarterly, 108 (2), 239-253.

8. Levy, J.S. (1983) ‘Misperception and the Causes of War: Theoretical Linkages and Analytical Problems’ World Politics, 36 (1), 76-99.

9. Levy, J.S. (1986) ‘Organisational Routines and the Causes of War’ International Studies Quarterly, 30 (2), 193-222.

10. McLean, I. (1996) The Concise Oxford Dictionary of Politics.Oxford:OxfordUniversity Press.

11. van Evera, S. (1998) ‘Offense, Defense, and the Causes of War’ International Security, 22 (4), 5-43.

12. Wikipedia, 13th March 2006, Margaret Thatcher, online, only edition,St Petersburg, Wikipedia, 14/3/06,

Written by: Andrew Jones
Written at: Exeter University
Date: March 2006

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