How Accurate is Democratic Peace Theory?

What is the Democratic Peace Theory and to What Extent is it Accurate in Regards to the War Proneness of Democratic States?

Democratic peace theory originates from the 1795 essay by Immanuel Kant, ‘On Perpetual Peace’[1]. The premise of Kant’s work is that peace is not a natural condition in world politics and that, through the application of republicanism and liberty, politics should exist to maintain a peaceful order of republican states established through civil constitutions and abiding by international laws. The continuation of Kant’s strain of thought, that the form of government controlling a state influences the tendency of that state to go to war, was continued into the twentieth century. This included the utopian ideology of ‘Wilsonianism’[2] following the First World War and later, throughout the 1970’s and 1980’s, through the work of academics such as Doyle[3] and Small & Singer[4], as well as post-Cold War academics throughout the 1990’s, such as Ray[5], Bremer[6] and Chan[7]. Such work ‘runs counter to the realist and neorealist theoretical traditions that have dominated the field of international politics.’[8] The theory – that liberal democracies tend to go to war less frequently than other forms of state governments – is a controversial one, with both strengths and weaknesses, supporting and weakening points, although the academic work surrounding the debate has shown the scales to be tipped towards support for the theory.

Democratic peace theory is reliant on the ideology of liberalism. The liberal ideology of civil liberties such as personal and political freedoms, democracy and economic growth, are paired with the concepts of democratic institutions and fairly elected governments that have been selected from a choice of political groups. A liberal democracy can therefore be defined as ‘a state that instantiates liberal ideas, one where liberalism is the dominant ideology and citizens have leverage over war decisions.’[9] Democratic peace is the theory that liberal democracies are less likely to go to war with one another as with other forms of government, specifically due to the nature of liberal political ideology and the pacifying influence of democracy.

The premise of the theory is that liberals believe that individuals, regardless of government, are fundamentally the same; that going to war against a fellow liberal democracy would be harmful to one’s own well-being due to the damage to the peace necessary for liberal democracies to economically exist in. Peace is to be maintained through political negotiation and war only used against illiberal and undemocratic states in order to maintain the peaceful status quo. Peace is a prerequisite for self-determination and material gain, key liberal concepts, and hence it is argued, by proponents of the theory, that liberal democracies are less likely to break this peace unless to restore their own liberal status – war against another liberal democracy therefore would unnecessarily break the peace necessary for liberalism to exist. Relations between liberal and illiberal states may be less stable, but the democratic peace theory argues that as long as both are free democracies, then war is more likely to be avoided than when a liberal democracy is confronted with a non-democratic state.

Two strands of thought surrounding the theory exist in parallel; structural and normative theories. The structural side of the democratic peace theory is concerned with how liberal institutions within a state encourage and participate in free debate, in theory removing the capacity of leaders to follow ambitions outside of the public interest. The decision to go to war taken within a liberal democracy must first pass through several constitutional institutions that place constraints on the ability to take quick, single-minded decisions. Hence, the liberal democracy is deemed rational and (in theory) allows the public to effectively control the decision to go to war.

The second strand is more abstract; – the normative side of the democratic peace theory argues that it is the liberal ideology that prevents wars between liberal democratic states. Wars against fellow liberal states would be unjust and disrupt the peace that liberal democracies regard as essential to individual development. The importance of perception in highlighted here; states may not regard another state as either liberal or democratic and hence their attitude towards such a state is altered, often towards a more aggressive stance. An example of this is the War of 1812, fought when ‘almost no Americans considered England a democracy.’[10] These two strands of the democratic peace theory work in tandem (a ‘synergy’[11]) to influence foreign policy decisions; – it is the democratic constraints and ideological pressures that contribute to leaders’ unwillingness to go to war with fellow liberal democracies.

There are many supporting arguments in favour of the democratic peace theory, drawing from multiple academic areas. The use of statistical analysis by proponents of the theory has indicated that historically, there have been fewer wars between liberal democracies than between different types of governments. The academic Bremer states; ‘even after controlling for a large number of factors… democracy’s conflict-reducing effect remains strong.’[12] This statistical analysis took into account the possible influences of factors such as alliance structures, economic wealth and political stability to produce a comprehensive statistical analysis of the ‘conflict-proneness’[13] of democratic governments.

Democracies have made up a small percentage of the total number of state powers on the world stage until relatively recently, hence although the total number of military engagements between democratic state has increased, this has to be tempered with the knowledge that as the number of engagements has increased, the frequency of such engagements has not kept up to speed with the increasing number of democracies. Hence, it is argued that this disparity between the expected number of inter-democratic engagements and the rising number of democratic states is accounted for by the democratic peace theory.

Arguments against this research have focused on the argument that much of the evidence used to support the statistical analyses was taken from the Cold-War era. As argued by opponents to the theory such as Farber & Gowa[14], democracies only avoided confrontation in order to oppose the larger threat of the Soviet Union and the spread of authoritarianism, hence skewing the data in favour of the democratic peace theory. The counter-argument made is that through multi-variable analysis of historical statistical data[15], this can be ruled out as an influencing factor as the political environment has been accommodated for in research; this is problematic, as translating complex political context into quantitative measurements is inherently open to different interpretations. However, the work of Bremer[16] and Maoz & Russett[17] ‘convincingly demonstrates’[18] the ‘tendency for democratic pairs of states to be less likely than other pairs to become involved in serious, militarised disputes.’[19]

Another source of support for the democratic peace theory has come from the theoretical base argued for by Bueno de Mequita; that going to war affects the chances of a democratic government’s leader being re-elected. The premise of this argument is that the probability of a liberal democratic leader falling from power in the wake of a war is significantly higher than in other forms of government, namely authoritarian or single-party states. As Bueno de Mequita puts it, leaders ‘desire to remain in office.’[20] The related argument made by Lake[21] is that due to the relative economic wealth and political stability in most democracies, such states are able to allocate more resources to national security; hence most democracies form ‘formidable targets’[22] in the eyes of democratic leaders, targets viewed as too strong to go to war against for fear of a costly military engagement and the associated negative impact on the personal political success of the state’s leaders. Hence, as Silverson[23] argues, democracies have tended to go to war against states that they have a high probability of beating militarily; such states tend to be an alternative form of government.

A recent example would be the 2003 US/British invasion of Iraq. Opponents to the theory state that although this may be theoretically true, the theory fails to take into account intra-state influences, such as religious divisions. An example of this is the 2006 conflict between Israel and the democratically-elected (but by no means liberal) Hamas government of Gaza; the Palestinian-Israeli conflict’s religious undertones were a key factor in determining the outbreak of conflict, despite the fact that both governments were democratically elected. Therefore, it must be remember that the leaders of democracies are elected by the people of that state; this may mean that a particularly hawkish and war-mongering electorate may install a leader that is more likely to use military force to pursue policy aims in order to satisfy their voter base.

The democratic peace theory cannot be viewed as a template for guiding political action; simply because two states are liberal democracies by no means rules out the possibility of war between them. However, due to the normative influence on liberal democracies (the liberal ideologies, as stated previously, that guide and shape both foreign policy and the state’s outlook towards the rest of the world), liberal democracies are theoretically less likely to go to war with one another. Indeed it is this normative theory, rooted in the idea that liberals are not inclined to go to war with fellow liberals, that has become the focal point of many researchers. Chan, for example, states; ‘normative explanations of the democratic peace theory have been shown to be persuasive than structural ones.’[24]

The theory can be falsified; the focus of many supporters of the theory has been the ability to classify conflicts and states, (although there has been debate over the dividing lines of terminology), into conflicts between democracies and conflicts not between democracies. ‘…well developed theoretical bases reinforce a lengthy list of systematic empirical analyses in support of that proposition [democratic peace theory]’[25]; Ray, having formulated an extensive and thorough analysis of the democratic peace theory, states that when viewed holistically the balance tips in favour of support for the theory. Indeed, when analysed through the multiple analytical lenses that Ray cites, credible counter-arguments emerge to the democratic peace theory. However, despite the relative strength of these arguments, proponents of the theory have sufficiently defended their academic position; the democratic peace theory is far from a clear-cut scientific theory, however when asked ‘is peace between democracies more likely than peace between differing political leaderships?’ the answer must be given as a conditional yes.

[1] I. Kant, ‘On Perpetual Peace’, 1795, Oxford University Press, Oxford

[2] J. L. Ray, ‘Does Democracy Cause Peace’, Annual Review of Political Science 1 (1998), Page 27

[3] M. W. Doyle, ‘Liberalism and World Politics’, American Political Science Review (1986), 80:1151, Page 69

[4] M. Small and J. Singer, ‘The War Proneness of Democratic Regimes’, Jerusalem Journal of International of International Relations (1976), 1:50, Page 69

[5] J. L. Ray, ‘Wars Between Democracies: Rare or Non-Existent?’, International Interactions (1993), 18:251 Page 49

[6] S. A. Bremer, ‘Democracy and Interstate Conflict’, International Interactions (1993), 18:231 Page 49

[7] S. Chan, ‘In Search of Democratic Peace’, Mershon International Studies Review, 41:59 Page 92

[8] J. L. Ray, ‘Does Democracy Cause Peace’, Annual Review of Political Science 1 (1998), Page 27

[9] J. M. Owen, ‘How Liberalism Produces Democratic Peace’, International Security (1994), 19:2, Page 89

[10] J. M. Owen, ‘How Liberalism Produces Democratic Peace’, International Security (1994), 19:2, Page 90

[11] Ibid, Page 92

[12] S. A. Bremer, ‘Democracy and Interstate Conflict’, International Interactions (1993), 18;231 Page 49

[13]J. L. Ray, ‘Does Democracy Cause Peace’, Annual Review of Political Science 1 (1998), Page 39

[14] Farber & Gowa, ‘Common Interests or Common Polities: Re-Interpreting the Democratic Peace Theory’, Journal of Politics (1997), 59:393 Page 17

[15] J. L. Ray, ‘Does Democracy Cause Peace’, Annual Review of Political Science 1 (1998), Page 41

[16] S. A. Bremer, ‘Democracy and Interstate Conflict’, International Interactions (1993), 18;231

[17] Maoz & Russett, ‘Is the Lack of Conflict Amongst Democratic States a Statistical Artefact?’, International Interactions (1992), 17:245 Page 67

[18]J. L. Ray, ‘Does Democracy Cause Peace’, Annual Review of Political Science 1 (1998), Page 41

[19] Ibid.

[20] B. Buena de Mesquita & R. Silverson, ‘War and the Survival of Political Leaders: A Comparative Study of Regime Types and Political Accountability’, American Political Science Review (1995), 86:63 8, Page 846

[21] D. Lake, ‘Powerful Pacifists: Democratic States and War’, American Political Science Review (1992),  86:24, Page 37

[22]J. L. Ray, ‘Does Democracy Cause Peace’, Annual Review of Political Science 1 (1998), Page 41

[23] R. M. Silverson, ‘Democracies and War Participation: In Defence of the Institutional Constraints Argument’, European Journal of International Relations (1995), 1:481 Page 89

[24] S. Chan, ‘In Search of Democratic Peace’, Mershon International Studies Review, 41:59 Page 92

[25] J. L. Ray, ‘Does Democracy Cause Peace’, Annual Review of Political Science 1 (1998), Page 43


Written by: James Bingham
Written at: King’s College, London
Written for: Dr Thomas Rid
Date written: February 2012


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