International Relations: Theoretical Approaches to Causes of War

International Relations: Theoretical Approaches to Causes of War

For centuries, wars between opposing societies and/or nations have remained to be among the most important aspect of human civilization. They constitute an integral part of human history as its impacts continue to shape how societies or nations interact and undertake innovations, particularly in weaponry and surveillance technologies in order to emerge victorious in wars that they are involved in. Therefore, while war has remained to be an integral part of human civilization, the only changing aspect is how these wars are fought, especially at the international level. In their book The Globalization of World Politics: an Introduction to International Relations, John Baylis, Steve Smith, and Patricia Owens have provided several insightful theoretical approaches that explain the causes of war. This paper therefore identifies the best theoretical approach explaining the causes of war at the international level. Furthermore, it compares and contrasts the identified theoretical approach to other three theoretical approaches explaining the causes of war. Finally, it uses empirical examples of wars in the past 200 years to support the arguments put forward.  

Realism and War

The realism theoretical approach best explains the causes of war. This theoretical approach considers the balance of powers between states or groups of states to be the leading cause of wars (Baylis, Smith, and Owens 2011, 84-85). According to the approach, international affairs are characterized by struggle for power among self-interested states. Since self-interest is a rather permanent phenomenon, the realism approach appears to be more pessimistic concerning the world’s ability in eliminating conflict and war. Therefore, two main features characterize realism in international relations. Firstly, it identifies the human nature of self-interest as the starting point of wars. For instance, this theoretical approach to causes of war starts its argument by claiming that humans are inherently egoistic and self-interested to a level where their self-interest overcomes the established moral principles (Baylis, Smith, and Owens 2011, 86-87). Similarly, states as the main actors on the world stage are compelled to act in specific ways that advance their self-interest because of their sovereignty status, in which legally, there is no any other actor above it (Baylis, Smith, and Owens 2011, 5). Therefore, efforts by individual states in maximizing its national interest normally results to a struggle for power. The constant attempt by states in preventing each other from dominating in international affairs or interest eventually causes war. The absence of any sovereign body above the states that make up the international political system normally compels or inspires the states to depend on their own military resources in achieving their needs and desires. For example, World War I and World War II were largely caused by Germany’s aspirations to control Europe and other parts of the world (D’Anieri 2012, 181). Before and during World War I, the absence of an international body that regulated the behaviors of the states provided the then powerful states, such as Germany the opportunity to use its military strength to control and dominate the European nations for its own self-interests. Although the US had maintained some degree of neutrality during the First World War, it combined efforts with other European powers, such as Britain to defeat Germany as Germany’s domination of Europe could have posed a threat to US national security and overseas’ interests.

Secondly, neo-realism, which is a recently developed variant of realism, views the structure of the international system to be the main cause of war. Unlike the classical realists that view war as directly originating from self-interest actions by the sovereign states, the neo-realists consider the structure of the international system, which to a large extent is influenced by the distribution of power, to be the cause of war as it is affecting the behavior of all states (Baylis, Smith, and Owens 2011, 117). For example, during the Cold War, there existed mainly two centers of power, that is, the US and the Soviet Union. Such existence of two centers of power is referred to as bipolarity. Although the US and the Soviet did not directly engage each other in a war, their global influence caused wars in various parts of the world, for example, the Israeli-Arab War since 1947 to present. While the US appeared to support Israel through supplying it weapons, the Soviet Union did the same with the Arab nations. The end of the Cold War characterized by the collapse of the Soviet Union left the US as the only center of power, a structure referred to as unipolarity. The unipolarity phase is characterized by relative stability due to the domination of a single state. The 2003 US invasion of Iraq can be viewed as an attempt to maintain unipolarity, hegemony, and avoid post-9/11 decline of the US by demonstrating the US’ willingness to use force. From the realism approach, the Iraqi invasion can also be justified as driven by the US’ self-interest in avoiding nuclear proliferation, and eliminating Iraqi’s weapons of mass destruction (WMD) that posed threat against the US and its allies (Baylis, Smith, and Owens 2011, 75). However, the world appears to be moving towards a phase of multipolarity, where there exist more than two centers of power. This has been characterized by the emergence of Brazil, Russia, India, and China (BRICs) as the new centers of power. For example, the re-emerged influence of Russia has been largely attributed to the recent Ukrainian armed conflict between Ukrainian government troops and the pro-Russia rebels. Russia is opposing Ukraine’s decision to join the European Union, which Russia views with suspicion as it is comprised of countries that are members of the North Atlantic Treaty Organization (NATO), a military alliance led by the US to mainly contain Russia’s security threat across Europe. Russia itself had sent its troops to Ukraine to support the pro-Russia rebels’ efforts in fighting the Ukrainian forces and their demand for greater autonomy of their region from the Ukrainian state.          

Liberalism and War

The liberalism thought is based on the belief in progress. In liberalism, humans are perceived as being perfectible, a perfectibility that can mainly develop through democracy and the valuing of ideas (Baylis, Smith, and Owens 2011, 103). Liberals are opposed to the realists’ perspective that war is a natural condition dominating world politics. Furthermore, liberals question the realists’ idea that the state, with its sovereignty status, is the main actor in political matters of international importance. They have also not denied that the role played by the state in the world stage is important. However, liberals perceive multinational corporations, transnational actors such as terrorist groups, and the international organizations as the main actors in some international political issue-areas (Baylis, Smith, and Owens 2011, 108-109). They tend to see the state as a set of bureaucracies, with each attempting to advance its own interests. Among the core ideals of liberalism include democracy, freedom and inevitable human progress, respect for scientific rationality, individual rights, and constitutionalism. From this approach, liberalism therefore view war as being caused by retrogressive ideals, such as the existence of undemocratic regimes, imperialism, and/or the collapse of the balance of power system or structure. The empirical evidence of such wars includes the military intervention by powerful countries regarded as democratic into the affairs or issue-areas of nondemocratic countries. For example, the 2011 military intervention in Libya by US and the European powers, such as France, in toppling Muammar Gaddafi’s regime that was perceived to be dictatorial and oppressive (Brown 2012, 276). Secondly, the U.S. led NATO military intervention in the Kosovo War, where it was bombing Yugoslavia troops accused of oppressing the Albanian people in Kosovo between 1998 and 1999 can also be explained using the liberalism theoretical approach because it was intended to restore democracy and respect for individual rights of the Albanian communities (Bacevich and Cohen 2001, 68-69). Contrary to the realism which views war as being caused by the inherent self-interest of the states, liberalism views the cause of war from a more positive or optimistic perspective. For example, they view war as a necessary tool for restoring democracy and respect for individual rights and constitutionalism to promote stability and peace for the common good.   

Marxism and War

The Marxist theoretical approach attempts to explain the situation of world politics from the perspective of world capitalist economy (Baylis, Smith, and Owens 2011, 135). It argues that classes, rather than states, are the most important actors in the world economy. It emphasizes that the behavior of all other actors is ultimately explainable or understandable by class forces. From this perspective, Marxists consider states, multinational corporations, and even international organizations as a representation of the dominant class interests in the global economic systems (Baylis, Smith, and Owens 2011, 134-135). Unlike the realism and liberalism approaches, Marxism views war as being caused by the capitalist economic system that produces class conflict, which can eventually escalate into a full-blown war. Marxists view imperialism as being the highest level of capitalism, whereby the oppression of lower class by the upper causes war.

The Marxism theoretical approach best explains the cause of wars for independence across Africa throughout the 20th century against the European colonial powers. The economic relationship between the colonies and the colonial powers was greatly in favor of the colonial powers. This oppressive economic relationship was opposed by various African national liberation movements, resulting in fierce wars across the continent, especially in the 1950s and ‘60s. Second, the increased international demand for strategic minerals such as gold, copper, nickel, uranium, among others, that are of strategic interest to the survival of the automobile, aircraft, satellite and communications, and weapons and nuclear industries in both the developed Eastern and Western economies have continued to cause war in the poorer countries where these minerals are exploited (Francis 2006, 47). For example, the Cold War political, economic and strategic struggles that took place in Africa resulted in violent civil wars in several African countries, such as Congo, Mozambique, and Angola. Until presently, mineral-rich Democratic Republic of Congo is still experiencing civil war, in which government and rebels use money generated from the sale of these strategic minerals to developed countries to purchase weapons and finance their wars (Book 2009, 149). These weapons are mostly manufactured by developed countries, some of which are reluctant to ban the supply of arms to this country. Some developed nations that seek to control such strategic minerals usually accomplish their mission through establishing oppressive regimes in those countries to enhance their access to such minerals. Unlike the liberals who view the US invasion of Iraq as a strategy of instilling democracy in a country that was ruled by dictator Saddam Hussein who was believed to support terrorism and manufacture weapons of mass destruction, Marxists normally insist that the US’ main objective was to control the Iraqi oil in order to meet its energy needs for economic growth purposes. Marxism approach to the cause of war is quite similar to that of realism, as they both emphasize it is driven by self-interest. The difference between these two is that the Marxism theoretical approach views wars as being caused by the oppression of the developing nations by the developed ones through the capitalistic economic system, rather than other avenues, such as military and political tactics (Baylis, Smith, and Owens 2011, 133-135).


In recent years, the use of post-colonialism approach to explain causes of war has increased significantly. Unlike the approaches of realism, liberalism, and Marxism that largely focused on how European problems caused wars across Europe, the post-colonialism approach focuses more on the impact of colonial powers domination in the global south (Baylis, Smith, and Owens 2011, 184). For instance, the boundaries that were established by colonial powers to minimize conflict with other colonial powers while simultaneously strengthen their grip of their colonies have been found to be a constant cause of wars in the global south. However, the imprecise delimitation of colonial boundaries, and the post-colonial regime’s inheritance of strife-ridden territories as opposed to cohesive states have been a source of conflict and war in some countries. An empirical example of this is the Vietnam-Cambodia-Laos-China boarders where military minority groups and separatist movements, frequently supported by foreign forces, were opposed to effective state control, particularly in the remote and inaccessible frontier zones after the Second World War (St. John and Schofield 1998, 21). During the First Indochina Conflict (1945-1954), in which France attempted to reassert its control over the region, and the Second Indochina Conflict (1954-1975), in which the US supported non-communist regimes in Cambodia, Laos, and Vietnam, played a significant role in escalating instability in the Indochina borderlands. For example, the US attempt to stop the flow of men and goods from the Democratic Republic of Vietnam south along the Ho Chi Minh Trail to the Republic of Vietnam caused extensive bombing along the Cambodia-Vietnam and Laos-Vietnam borders, thereby generating considerable refugee movement in the frontier zones (St. John and Schofield 1998, 21). In Africa, most countries that fell under the French colonial rule, such as Cote d’Ivoire (Ivory Coast), Democratic Republic of Congo (DRC), and Central African Republic (CAR), have lacked political stability since independence, as they often experience armed conflict (Azikiwe 2010, 115). Unlike in the French colonies where France adopted assimilation principles, the British colonies that were granted full autonomy have been enjoying more political and economic stability. Contrary to the realism, liberalism and Marxism approaches, post-colonial approaches have been instrumental in understanding how conflict in the global south is intertwined with their past and present interactions with their colonial powers.                   


It is evident that the causes of war are best explained using the realism theoretical approach. The realism approach emphasizes that wars are mainly caused by the struggle for power between sovereign states that seek to advance their own interests. Since such interests are always conflicting, the states involved in power struggle can eventually engage each other in armed conflict, with each seeking to dominate the other in order to reap the benefits of being in control. Other theoretical approaches also appear to borrow their main ideas and concepts from the realism approach. For instance, the Marxism argument that war originates from the world’s capitalist economy shows that the powerful nation’s efforts to control the world economy is one of the major causes of war. For example, the colonial domination that benefitted the economies of developed countries through exploitation of resources in less developed countries was the main cause of violent independence wars worldwide. The Western nations scramble for oil and minerals essential for their economic development have continued to cause wars in Iraq and Central Africa. Finally, the post-colonial approach acknowledges that wars in the global south are being caused by the colonial power’s attempt to reassert control over their former colonies to advance their interests, such as in the case of the First and Second Indochina conflicts.        


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