Democratic peace theory

The democratic peace theory or simply democratic peace (often DPT) is a theory in international relations, political science, and philosophy which holds that democracies—specifically, liberal democracies—never or almost never go to war with one another.

The original theory and research on wars has been followed by many similar theories and related research on the relationship between democracy and peace, which has led to claims that lesser conflicts than wars are also rare between democracies, and that systematic violence is in general less common within democracies.

History

The democratic peace theory is a relatively new development. No early author seems to have considered it true. One explanation is that democratic governments were scarce before the late 19th century.

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Immanuel Kant

It was Immanuel Kant who first foreshadowed the theory in his essay Perpetual Peace written in 1795, although he thought that liberal democracy was only one of several necessary conditions for a perpetual peace. Kant's theory was that a majority of the people would never vote to go to war, unless in self defense. Therefore, if all nations were democracies, it would end war, because there would be no aggressors. Other explanations have been proposed since, but the modern theory is principally the empirical claim that democracies rarely or never fight.

Dean Babst, a criminologist, was the first to do statistical research on this topic. He wrote an academic paper supporting the theory in 1964 in Wisconsin Sociologist; he published a slightly more popularized version, eight years later, in the trade journal Industrial Research. Both versions initially received little attention.

J. David Singer and Melvin Small (1976) eventually responded and denied that democracies were in general less war-like than other nations. However, they found only two marginal cases of democracies fighting each other. This paper was published in a political science journal, the Jerusalem Journal of International Relations, which finally brought more widespread attention to the theory, as did Michael Doyle's (1983) lengthy discussion of the topic. Rudolph J. Rummel was another early researcher and drew considerable lay attention to the subject in his later works.

Maoz & Abdolali (1989) extended the research to lesser conflicts than wars. Bremer (1992) and Maoz & Russett (1992) found the correlation between democracy and peacefulness remained significant after controlling for many possible confounding variables. This moved the theory into the mainstream of social science. Supporters of Realism in international relations and others responded by raising many new objections. Other researchers attempted more systematic explanations of how democracy might cause peace, and of how democracy might also affect other aspects of foreign relations such as alliances and collaboration.

There have been numerous further studies in the field since these pioneering works. Most studies have found some form of democratic peace exists, although neither methodological disputes nor doubtful cases are entirely resolved (Kinsella 2005).

Influence

ASEAN flag. In 2003 ASEAN "subscribed to the notion of democratic peace, which means all member countries believe democratic processes will promote regional peace and stability." Also the non-democratic members "all agreed that it was something all member states should aspire to."

The democratic peace theory has been extremely divisive among political scientists. It is rooted in the idealism in international relations and classical liberalism traditions; and is opposed to the previously dominant theory, realism in international relations. However, democratic peace theory has come to be more widely accepted and has in some democracies affected policy.

Presidents of both the major American parties have expressed support for the theory. Former President Bill Clinton of the Democratic Party: "Ultimately, the best strategy to ensure our security and to build a durable peace is to support the advance of democracy elsewhere. Democracies don't attack each other." Current President George W. Bush of the Republican Party: "And the reason why I'm so strong on democracy is democracies don't go to war with each other. And the reason why is the people of most societies don't like war, and they understand what war means.... I've got great faith in democracies to promote peace. And that's why I'm such a strong believer that the way forward in the Middle East, the broader Middle East, is to promote democracy."

Some fear that the democratic peace theory may be used to justify wars against nondemocracies in order to bring lasting peace, in a democratic crusade (Chan 1997, p. 59). Woodrow Wilson in 1917 asked Congress to declare war against Imperial Germany, citing Germany's sinking of American ships due to unrestricted submarine warfare and the Zimmerman telegram, but also stating that "A steadfast concert for peace can never be maintained except by a partnership of democratic nations" and "The world must be made safe for democracy." Some point out that the democratic peace theory has been used to justify the 2003 Iraq War, others argue that this justification was used only after the War had already started. However, research shows that attempts to create democracies by using external force has often failed eventually. Those attempts that have succeeded, like creating a stable democracy in occupied Japan after WWII, have involved a drastic change of the whole political culture. Supporting internal democratic movements and using diplomacy may be far more successful and less costly. Thus, the theory and related research, if they were correctly understood, may actually be an argument against a democratic crusade (Weart 1998), (Owen 2005), (Russett 2005).

Definitions

A democratic peace theory has to define what it means by "democracy" and what it means by "peace" (or, more often, "war").

Democracy

Freedom House classifies the green nations in the map as liberal democracies.

Democracies have been defined differently by different theorists and researchers; this accounts for some of the variations in their findings. Some examples:

Kant (1795) opposed direct democracy since it is "necessarily despotism, as it establishes an executive power contrary to the general will; all being able to decide against one whose opinion may differ, the will of all is therefore not that of all: which is contradictory and opposite to liberty." Instead, Kant favors a constitutional republic where individual liberty is protected from the will of the majority.

Singer (1976) define democracy as a nation that (1) holds periodic elections in which the opposition parties are as free to run as government parties, (2) allows at least 10% of the adult population to vote, and (3) has a parliament that either controls or enjoys parity with the executive branch of the government.

Doyle (1983) requires (1) that "liberal régimes" have market or private property economics, (2) they have polities that are externally sovereign, (3) they have citizens with juridical rights, and (4) they have representative governments. Either 30% of the adult males were able to vote or it was possible for every man to acquire voting rights as by attaining enough property. He allows greater power to hereditary monarchs than other researchers; for example, he counts the rule of Louis-Philippe of France as a liberal régime.

Ray (1995) requires that at least 50% of the adult population is allowed to vote and that there has been at least one peaceful, constitutional transfer of executive power from one independent political party to another by means of an election.

Rummel (1997) states that "By democracy is meant liberal democracy, where those who hold power are elected in competitive elections with a secret ballot and wide franchise (loosely understood as including at least 2/3rds of adult males); where there is freedom of speech, religion, and organization; and a constitutional framework of law to which the government is subordinate and that guarantees equal rights."

Robert Dahl (1994?)

Weart (1998). See Never at War.

Non-binary classifications

The above definitions are binary, classifying nations into either democracies or nondemocracies. Many researchers have instead used more finely grained scales. One example is the Polity data series which scores each state on two scales, one for democracy and one for autocracy, for each year since 1800; as well as several others. The use of the Polity Data has varied. Some researchers have done correlations between the democracy scale and belligerence; others have treated it as a binary classification by (as its maker does) calling all states with a high democracy score and a low autocracy score democracies; yet others have used the difference of the two scores, sometimes again making this into a binary classification (Gleditsch 1992).

Young democracies

Several researchers have observed that many of the possible exceptions to the democratic peace have occurred when at least one of the involved democracies was very young. Many of them have therefore added a qualifier, typically stating that the peacefulness apply to democracies older than 3 years (Doyle 1983), (Russett 1993), (Rummel 1997), (Weart 1998). Rummel (1997) argues that this is enough time for "democratic procedures to be accepted, and democratic culture to settle in." Additionally, this may allow for other states to actually come to the recognition of the state as a democracy. Mansfield and Snyder (2005) find statistical evidence that young democracies and democratizing countries are more likely to fight wars than either stable democracies or stable autocracies. See below under Criticism and Counter-Criticism).

Wars and lesser conflicts

Quantitative research on international wars usually define war as a military conflict with more than 1000 killed in battle. This is the definition used in the Correlates of War Project which has also supplied the data for many studies on war. It turns out that most of the military conflicts in question fall clearly above or below this threshold (Ray 1995, p. 103).

Some researchers have used different definitions. For example, Weart (1998) defines war as more than 200 battle deaths. Russett (1993, p. 50), when looking at Ancient Greece, only requires some real battle engagement, involving on both sides forces under state authorization.

Militarized Interstate Disputes (MIDs), in the Correlates of War Project classification, are lesser conflicts than wars. Such a conflict may be no more than military display of force with no battle deaths. MIDs and wars together are "militarized interstate conflicts" or MICs. MIDs include the conflicts that precede a war; so the difference between MIDs and MICs may be less than it appears.

Statistical analysis and concerns about degrees of freedom are the primary reasons for using MID's instead of actual wars. Wars are relatively rare. An average ratio of 30 MID's to one war provides a richer statistical environment for analysis.

Wars

The straightforward argument for the democratic peace is: given the number of wars over the past two centuries, if democracies fought each other as often as any other pair of states, there should have been many wars between democracies. Instead, depending on the study, we find zero or very few, and the possible exceptions generally involve doubtful democracies. A review (Ray 1998) lists many studies finding that this peacefulness is statistically significant.

Possible exceptions to no wars

Main article: List of possible exceptions to democratic peace theory

Several researchers find no wars between well-established liberal democracies. Jack Levy (1988) made an oft-quoted assertion that the theory is "as close as anything we have to an empirical law in international relations".

Others see one or two exceptions. Some wars commonly suggested as exceptions are the Spanish-American War, the Continuation War and, recently, the Kargil War. Even some of those who see exceptions regard them as marginal cases.

Other authors simply describe war between democracies as "rare", "very rare", "rare or non-existent".

The question of no or few wars may be unimportant. Bremer (1992, 1993), who strongly supports the democratic peace, argues that it is impossible to prove a probability of exactly zero wars between democracies; thus is "fruitless to debate the question of whether democracies never or only very rarely fight one another". It is only possible to show a decrease in the probability of war.

However, at least one researcher (Rummel 1983) have argued that the inter-democratic peace is an absolute law. One exception will disprove the theory. Most researchers disagree (Gleditsch 1992).

The monadic peace and the dyadic peace

Most research is regarding the dyadic peace, that democracies do not fight one another. Very few researchers have supported the monadic peace, that democracies are more peaceful in general. There are some recent papers, which find a slight monadic effect. Müller and Wolff (2004), in listing them, agree "that democracies on average might be slightly, but not strongly, less warlike than other states," but general "monadic explanations is neither necessary nor convincing". They note that democracies have varied greatly in their belligerence against non-democracies. The most militant democracies since 1950 have been India, Israel, the United Kingdom and the United States.

Lesser conflicts

Stortinget. Norway was the first independent nation with complete universal suffrage in 1913

One problem with the research on wars is that, as the Realist Mearsheimer (1990, p. 50) put it, "democracies have been few in number over the past two centuries, and thus there have few opportunities where democracies were in a position to fight one another". Especially if using a strict definition of democracy, as by those finding no wars. Democracies have been very rare until recently. Even looser definitions of democracy, such as Doyle's, find only a dozen democracies before the late nineteenth century, and many of them short-lived or with limited franchise (Doyle 1983), (Doyle 1997, p. 261). Freedom House finds no independent state with universal suffrage in 1900.

Thus, despite the studies mentioned earlier, some argue that there is not enough data to show that the absence of wars between democracies is statistically significant, especially if trying to control for possible external factors. Wayman (1998), a supporter of the democratic peace, states: "If we rely solely on whether there has been an inter-democratic war, it is going to take many more decades of peace to build our confidence in the stability of the democratic peace."

Many researchers reacted to this by studying lesser conflicts instead, since they have been far more common. There have been many more MIDs than wars; the Correlates of War Project counts several thousands during the last two centuries. A review (Ray 2003) lists many studies that have reported that democratic pairs of states are less likely to be involved in MIDs than other pairs of states.

Another study (Hensel, Goertz & Diehl 2000) finds that after both states have become democratic, there is a decreasing probability for MIDs within a year and this decreases almost to zero within five years.

When examining the inter-liberal MIDs in more detail, one study (Wayman 2002) finds that they are less likely to involve third parties, the target of the hostility is less likely reciprocate, if the target reciprocates the response is usually proportional to the provocation, and the disputes are less likely to cause any loss of life. The most common action was "Seizure of Material or Personnel".

Studies find that the probability that disputes between states will be resolved peacefully is positively affected by the degree of democracy exhibited by the least democratic state involved in that dispute. Disputes between democratic states are significantly shorter than disputes involving at least one undemocratic state. Democratic states are more likely to be amenable to third party mediation when they are involved in disputes with each other (Ray 2003).

In international crises that include the threat or use of military force, one study finds that if the parties are democracies, then relative military strength has no effect on who wins. This is different from when nondemocracies are involved. These results are the same also if the conflicting parties are formal allies (Gelpi & Griesdorf 2001). Similarly, a study of the behavior of states that joined ongoing militarized disputes reports that power is important only to autocracies: democracies do not seem to base their alignment on the power of the sides in the dispute (Werner & Lemke 1997).

Internal violence

Most of this article discusses research on relations between states. However, there is also evidence that democracies have less internal systematic violence. For instance, one study finds that the most democratic and the most authoritarian states have few civil wars, and intermediate regimes the most. The probability for a civil war is also increased by political change, regardless whether toward greater democracy or greater autocracy. Intermediate regimes continue to be the most prone to civil war, regardless of the time since the political change. In the long run, since intermediate regimes are less stable than autocracies, which in turn are less stable than democracies, durable democracy is the most probable end-point of the process of democratization (Hegre et al. 2001). One study finds that the most democratic nations have the least terrorism (Abadie 2004). One study finds that genocide and politicide are rare in democracies (Harff 2003). Another that democide is rare (Rummel 1997).

One study (Davenport & Armstrong II 2004) lists several other studies and states: "Repeatedly, democratic political systems have been found to decrease political bans, censorship, torture, disappearances and mass killing, doing so in a linear fashion across diverse measurements, methodologies, time periods, countries, and contexts." It concludes: "Across measures and methodological techniques, it is found that below a certain level, democracy has no impact on human rights violations, but above this level democracy influences repression in a negative and roughly linear manner." One study (Davenport & Armstrong II 2003) states that thirty years worth of statistical research has revealed that only two variables decrease human rights violations: political democracy and economic development. Of this democracy is more important and more easily created.

Possible explanations for how democracy may cause peace

These theories have traditionally been categorized into two groups: explanations that focus on democratic norms and explanations that focus on democratic political structures (Gelpi & Griesdorf 2001). Note that they usually are meant to be explanations for little violence between democracies, not for a low level of internal violence in democracies.

Several of these mechanisms may also apply to oligarchies. The book Never at War find evidence for an oligarchic peace. One example is the Polish-Lithuanian Commonwealth, in which the Sejm resisted and vetoed most royal proposals for war, like those of Władysław IV Vasa.

Democratic norms

One example from the first group is that the democratic culture may make the leaders accustomed to negotiation and compromise (Weart 1998), (Müller & Wolff 2004). Another that a belief in human rights may make people in democracies reluctant to go to war, especially against other democracies. The decline in colonialism, also by democracies, may be related to a change in perception of non-European peoples and their rights (Ravlo & Gleditsch 2000).

Bruce Russett (1993, p. 5-11, 35, 59-62, 73-4) also argues that the democratic culture affect the way leaders resolve conflicts. In addition, he holds that a social norm emerged toward the end of the nineteenth, that democracies should not fight each other, which strengthened when the democratic culture and the degree of democracy increased, for example by widening the franchise. Increasing democratic stability allowed partners in foreign affairs to perceive a nation as reliable democratic. The alliances between democracies during the two World Wars and the Cold War also strengthened the norms. He sees less effective traces of this norm in Greek antiquity.

Mousseau (2000) argues that it is market-oriented development that creates the norms and values that explain the democratic peace. When opportunities to contract in the market are widespread, as in market-oriented developed countries, a culture of contracting emerges that encourages shared respect for individualism, negotiations, compromise, respect for the law, and equality before the law. Constrained by voters, democratically elected leaders in market-oriented developed countries abide by these norms. In contrast, voters in democracies without developed market economies, and the leaders in nondemocracies, have other norms and values that encourage conflict.

Democratic political structures

The case for institutional constraints goes back to Kant (1795), who wrote :

"[I]f the consent of the citizens is required in order to decide that war should be declared (and in this constitution it cannot but be the case), nothing is more natural than that they would be very cautious in commencing such a poor game, decreeing for themselves all the calamities of war. Among the latter would be: having to fight, having to pay the costs of war from their own resources, having painfully to repair the devastation war leaves behind, and, to fill up the measure of evils, load themselves with a heavy national debt that would embitter peace itself and that can never be liquidated on account of constant wars in the future"

Democracy thus gives influence to those most likely to be killed or wounded in wars, and their relatives and friends (and to those who pay the bulk of the war taxes) Russett (1993, p. 30). This monadic theory must, however, explain why democracies do attack non-democratic states. One explanation is that these democracies were threatened or otherwise were provoked by the non-democratic states. Doyle (1997, p. 272) argued that the absence of a monadic peace is only to be expected: the same ideologies that cause liberal states to be at peace with each other inspire idealistic wars with the illiberal, whether to defend oppressed foreign minorities or avenge countrymen settled abroad. Doyle also notes (p. 292) liberal states do conduct covert operations against each other; the covert nature of the operation, however, prevents the publicity otherwise characteristic of a free state from applying to the question

It has also been suggested that democracies rarely fight wars because war, or impending war, tends to destroy democracy; This argument depends only on the internal conditions of one state; it shouldn't matter whether the war is with a democracy or not. It is therefore a mechanism for the general, or monadic, peacefulness of democracies. Mousseau and Shi (1999) finds this explanation unlikely. They studied all states, inquiring whether the onset of war decreased democracy, either temporarily or permanently, and found most wars had no significant effect, but some did.

Studies show that democratic states are more likely than autocratic states to win the wars. One explanation is that democracies, for internal political and economic reasons, have greater resources. This might mean that democratic leaders are unlikely to select other democratic states as targets because they perceive them to be particularly formidable opponents. One study finds that interstate wars have important impacts on the fate of political regimes, and that the probability that a political leader will fall from power in the wake of a lost war is particularly high in democratic states (Ray 1998).

As described in (Gelpi & Griesdorf 2001), several studies have argued that liberal leaders face institutionalized constraints that impede their capacity to mobilize the state’s resources for war without the consent of a broad spectrum of interests. Moreover, these constraints are readily apparent to other states and cannot be manipulated by leaders. Thus, democracies send credible signals to other states of an aversion to using force. These signals allow democratic states to avoid conflicts with one another, but they may attract aggression from nondemocratic states. Democracies may be pressured to respond to such aggression—perhaps even preemptively—through the use of force. Also as described in (Gelpi & Griesdorf 2001), studies have argued that when democratic leaders do choose to escalate international crises, their threats are taken as highly credible, since there must be a relatively large public opinion for these actions. In disputes between liberal states, the credibility of their bargaining signals allows them to negotiate a peaceful settlement before mobilization.

A game-theoretic explanation similar to the last two above is that the participation of the public and the open debate send clear and reliable information regarding the intentions of democracies to other states. In contrast, it is difficult to know the intentions of nondemocratic leaders, what effect concessions will have, and if promises will be kept. Thus there will be mistrust and unwillingness to make concessions if at least one of the parties in a dispute is a nondemocracy (Levy & Razin 2004).

Criticisms and counter-criticisms

There are several logically distinguishable classes of criticism. Note that they usually apply to no wars or few MIDs between democracies, not to little systematic violence in democracies. See also the discussion of specific historic conflicts above.

Refutation by the Kosovo War

Peter Singer and Leif Wenar both believe that the war in Kosovo is a serious problem for the theory [Singer, "One World", p. 136]. Slobodan Milosevic had won three elections - twice as President of Serbia and once as President of Yugoslavia - and it is clear that he had widespread support in the country during this period. Singer admits that Yugoslavia still had limits to its openness and freedom, but these limits were not thought to be more extensive than those found in several Western countries that are considered to be "democracies".

Definitions used for liberal democracy and war

Democracy has meant different things at different times but the research has applied the same criteria to all periods.

Definitions of democracy that require an actual transfer of power between different political parties sometimes exclude long periods often viewed as democratic. For example, the United States until 1800, India from independence until 1979, and Japan until 1993 (Ray 1995, p. 100).

Some democratic peace researchers require that the executive result from a substantively contested election. This may be a cautious definition: For example, the National Archives of the United States notes that "For all intents and purposes, George Washington was unopposed for election as President, both in 1789 and 1792". (Under the original provisions for the Electoral College, there was no distinction between votes for President and Vice-President: each elector was required to vote for two distinct candidates, with the runner-up to be Vice-President. Every elector cast one of his votes for Washington, John Adams received a majority of the other votes; there were several other candidates: so the election for Vice President was contested.)

The military affairs columnist of the newspaper Asia Times criticizes the theory as subject to the no true Scotsman problem. Exceptions are explained away as not being between real democracies or being real wars.

There may be errors in the data and the classification

For example, there may be mistakes regarding battle deaths in the data set used, such as the Correlates of War Project data.

There may be errors in methodology

Spiro's (1994) made several criticisms of the statistical methods used. Russett (1995) and a series of papers described by Ray (2003) responded to this, for example with different methodology.

Some democratic peace researchers have been criticized for reclassifying some specific conflicts or political systems without checking and correcting the whole data set used similarly. Supporters and opponents of the democratic peace agree that this is bad statistics, even if a plausible case can be made for the correction (Bremer 1992), (Gleditsch 1995), (Gowa 1999).

Other explanations than democracy for the peace

It may not be democracy itself but some other external factor(s) which happened to be associated with democratic states that explain the peace.

Correlation is not causation

Correlation is not causation. However, many studies, as those discussed in (Ray 1998), (Ray 2005), (Oneal & Russett 2004), supporting the theory have controlled for many possible alternative causes of the peace. Examples of factors controlled for are geographic distance, geographic contiguity, power status, alliance ties, militarization, economic wealth and economic growth, power ratio, and political stability. These studies have often found very different results depending on methodology and included variables, which has caused criticism. It should be noted that DPT does not state democracy is the only thing affecting the risk of military conflict. Many of the mentioned studies how found that other factors are also important. However, a common thread in virtually all results is an emphasis on the relationship between democracy and peace.

Several studies have also controlled for the possibility of reverse causality from peace to democracy (Mousseau & Shi 1999),(Reiter 2001), (Reuveny & Li 2003).

Weart (1998) argues that the peacefulness appears and disappears rapidly when democracy appears and disappears. This makes it unlikely that variables that change more slowly are the explanation.

Wars tend very strongly to be between neighboring states. Gleditsch (1995) showed that the average distance between democracies is about 8000 miles, the same as the average distance between all states. He believes that the effect of distance in preventing war, modified by the democratic peace, explains the incidence of war as fully as it can be explained.

Mousseau argues that a culture of contracting in advanced market-oriented economies may cause both democracy and peace (2000; 2002; 2003; 2005). Low economic development may hinder development of liberal institutions and values. Hegre (2000) and Souva (2003) reach similar conclusions. These studies indicate that democracy, alone, is an unlikely cause of the democratic peace. Mousseau (2005) finds that democracy is a significant factor only when both democracies have levels of economic development well above the global median. The poorest 21% of the democracies studied, and the poorest 4-5% of current democracies, are significantly more likely to fight each other. Oneal & Russett (2004) list several other studies which find smaller effects from economic development when controlling for one of the Kantian variables, trade. Mousseau, Hegre & Oneal (2003) find that when also controlling for trade, 91% of all the democratic pairs had high enough development for democracy to important during the 1885–1992 period and all in 1992. Hegre (2003) finds that democracy is correlated with civil peace only for developed countries, and for countries with high levels of literacy. Conversely, the risk of civil war decreases with development only for democratic countries. High economic development itself does not prevent war. WWI and WWII was fought between highly developed nations.

Realist explanations

Supporters of realism in international relations argue that it is not democracy that causes the peace. Spiro (1994) points out at some length that much of the democratic peace is in fact peace between allied democratic states, which have (unlike other alliances), not broken down into war between the allies. He regards this effect as the reality of the democratic peace; ascribing the rest of it to chance. However, this does not explain why democratic alliances are different.

Another realist, Layne (1994) analysed the crises and brinkmanship that took place between non-allied democratic great powers, during the relatively brief period when such existed. He found no evidence either of institutional or cultural constraints against war; indeed, there was popular sentiment in favor of war on both sides. Instead, in all cases, one side concluded that it could not afford to risk that war at that time, and made the necessary concessions. However, other researches have examined some of these crises and reached different conclusions, arguing that perceptions of democracy prevented escalation. Also, there are new explanations different from those that Layne criticized, like the game-theoretic one discussed below. In addition, if the realist explanation were true of all democracies, the results of crises between them would largely depend on their relative strength. A more recent study (Gelpi & Griesdorf 2001) denies this.

Probably the most well-known realist critic, Gowa (1999) finds that there were so few democracies before 1939 that the claims of the theory are not statistically significant. The peace between democracies during the 1945-1980 period she finds statistically significant. However, this is explained not be democracy, but by the external threat from the Communist states during the Cold War, which forced the democratic states to ally with one another. (Mearsheimer (1990) offers a similar analysis of the Anglo-American peace before 1945, caused by the German threat.)

Gowa's use of statistics has been criticized, with several other studies and reviews finding opposing results (Gelpi & Griesdorf 2001), (Ray 2003). Ray (1998) objects that the same arguments should show that the Communist bloc would be at peace within itself. Exceptions include the 1956 Hungarian Revolution, the Prague spring, the Sino-Soviet border conflict, the Soviet Invasion of Afghanistan, the Cambodian-Vietnamese War, and the Sino-Vietnamese War. The external threat did not prevent conflicts in the Western bloc when at least one of the involved states was a nondemocracy, such as the Turkish Invasion of Cyprus, the Falklands War, and the Football War. Note that some of these conflicts did not have more than a thousand battle deaths. One study (Ravlo & Gleditsch 2000) also notes that the explanation "goes increasingly stale as the post-Cold War world accumulates an increasing number of peaceful dyad-years between democracies."

Rosato (2003) criticizes many of the explanations for how democracy can cause peace and instead argues that American dominance, principally through NATO, explain the peace. This has been criticized for claimed logical errors, for not giving supporting statistical evidence, and for that actual statistical research contradict the explanation (Slantchev, Alexandrova & Gartzke 2005), (Kinsella 2005).

Supporters of the democratic peace do not deny that realist factors are also important. Research supporting the theory has also shown that factors such as geographic contiguity, alliance ties, and major power status impact interstate conflict behavior (Ray 2003).

Marxist explanations

Immanuel Wallerstein has argued that it is the global capitalist system that creates shared interests among the dominant parties, thus inhibiting potentially harmful belligerence.

Negri and Hardt take a similar stance, arguing that the intertwined network of interests in the global capitalism leads to the decline of individual nation states, and the rise of a global Empire which has no outside, and no external enemies. As a result, they write, "The era of imperialist, interimperialist, and anti-imperialist wars is over. (...) we have entered the era of minor and internal conflicts. Every imperial war is a civil war, a police action." (Hardt and Negri, 2000).

Kantian peace theory

Several studies find that democracy, more trade causing greater economic interdependence, and membership in more intergovernmental organizations reduce the risk of war. This is often called the Kantian peace theory since it is similar to Kant's earlier theory about a perpetual peace. These variables positively affect each other but each has an independent pacifying effect. For example, democracy may empower economic interest groups that may be opposed to disruptive wars (Russett & Oneal 2001), (Lagazio & Russett 2004), (Oneal & Russett 2004). However, some recent studies find no effect from trade but only from democracy (Goenner 2004), (Kim & Rousseau 2005).

It was Michael Doyle (1983, 1997) who reintroduced Kant's three articles into democratic peace theory. He argued that a pacific union of liberal states has been growing for the past two centuries. He denies that a pair of states will be peaceful simply because they are both liberal democracies; if that were enough, liberal states would not be aggressive towards weak non-liberal states (as the history of American relations with Mexico shows they are). Rather, liberal democracy is a necessary condition for international organization and hospitality (which are Kant's other two articles) — and all three are sufficient to produce peace. Other Kantians have not repeated Doyle's argument that all three in the triad must be present, instead stating that all three reduce the risk of war.

There may be limited consequences of the peace

The peacefulness may have various limitations and qualifiers and may not actually mean very much in the real-world.

Many democratic peace researchers do not count as wars conflicts which do not kill a thousand on the battlefield; thus they exclude for example the bloodless Cod Wars. However, as noted earlier, research has also found a peacefulness between democracies when looking at lesser conflicts.

Mansfield and Snyder (2005), while supporting the view that well-established liberal democracies don't make wars to each other, state that emerging democracies with weak political institutions are especially likely to go to war, whether or not they win, as a means of handling internal tension. They find that all wars between democracies involve one less than five years old, and that democratizing countries are even more warlike than stable autocracies. A review (Ray 2003) cites several other studies finding that this increase in the risk of war happens only if many or most of the surrounding nations are undemocratic. Ray also argues that since one of articles by Mansfield and Snyder were published in Foreign Affairs, they "obviously intended to discourage policies inspired by the democratic peace proposition that were designed to bring about such transitions."

It has been suggested that the peacefulness applies to similar regimes in general, not only democracies. Bennett (2006) finds that the most autocratic pairs of states have a reduced chance for conflicts, similar to that for the most democratic pairs. However, the democratic peacefulness is clearly stronger than the autocratic.

Democracies were involved in more colonial and imperialistic wars than other states during the 1816-1945 period. On the other hand, this relation disappears if controlling for factors like power and number of colonies. Liberal democracies have less of these wars than other states after 1945. This might be related to changes in the perception of non-European peoples, as embodied in the Universal Declaration of Human Rights (Ravlo & Glieditsch 2000).

Related to this is the human rights violations committed against native people, sometimes by liberal democracies. One response is that many of the worst crimes were committed by nondemocracies, like in the European colonies before the nineteenth century, in King Leopold II of Belgium's privately owned Congo Free State, and in Stalin's Soviet Union. England abolished slavery in British territory in 1833, immediately after the Reform Act 1832 had significantly enlarged the franchise. (Of course, the abolition of the slave trade had been enacted in 1807; and many DPT supporters would deny that England was a liberal democracy in 1833 when examining interstate wars.)

Hermann and Kegley (1995) argue that interventions between democracies are more likely to happen than projected by an expected model. They further argue (1996) that democracies are more likely to intervene in other liberal states than against countries that are non-democracies. Finally, they argue that these interventions between democracies have been increasing over time and that the world can expect more of these interventions in the future. The methodology used has been criticzed and more recent studies have found opposing results (Gleditsch, Christiansen & Hegre 2004).

Rummel argues that the continuing increase in democracy worldwide will soon lead to an end to wars and democide, possibly around or even before the middle of this century. The fall of Communism and the increase in the number of democratic states were accompanied by a sudden and dramatic decline in total warfare, interstate wars, ethnic wars, revolutionary wars, and the number of refugees and displaced persons. One report claims that the two main causes of this decline in warfare are the end of the Cold War itself and decolonization; but also claims that the three Kantian factors have contributed materially.

Academic relevance and derived studies

File:DP CHART V19.JPG

Charts arguing in favour of DPT. showing research by R. J. Rummel and others. High resolution PDF

File:DP BACKSIDE V 16.JPG

High Resolution PDF

Democratic peace theory is a well estabilished research field with more than a hundred authors having published articles about it. Several peer-reviewed studies mention in their introduction that most researchers accept the theory as an empirical fact.

Imre Lakatos suggested that what he called a "progressive research program" is better than a "degenerative" one when it can explain the same phenomena as the "degenerative" one, but is also characterized by growth of its research field and the discovery of important novel facts. In contrast, the supporters of the "degenerative" program do not make important new empirical discoveries, but instead mostly apply adjustments to their theory in order to defend it from competitors. Some researchers argue that democratic peace theory is now the "progressive" program in international relations. According to these authors, the theory can explain the empirical phenomena previously explained by the earlier dominant research program, realism in international relations; in addition, the initial statement that democracies do not, or rarely, wage war on one another, has been followed by a rapidly growing literature on novel empirical regularities. (Ray 2003), (Chernoff 2004), (Harrison 2005). Many of these derived studies have been mentioned above, for example those examining lesser conflicts and minor incidents.

Other examples are several studies finding that democracies are more likely to ally with one another than with other states, forming alliances which are likely to last longer than alliances involving nondemocracies (Ray 2003); several studies including (Weart 1998) showing that democracies conduct diplomacy differently and in a more conciliatory way compared do nondemocracies; one study finding that democracies with proportional representation are in general more peaceful regardless of the nature of the other party involved in a relationship (Leblang & Chan 2003); and another study reporting that proportional representation system and decentralized territorial autonomy is positively associated with lasting peace in postconflict societies (Binningsbø 2005).

Sources

Babst, Dean V. "Elective Governments--A Force For Peace." The Wisconsin Sociologist 3 (1, 1964): 9-14.

Babst, Dean V.. "A Force For Peace." Industrial Research (April 1972): 55-58.

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Beck, N., and Tucker R (1998). "Democracy and Peace: General Law or Limited Phenomenon?". Annual Meeting of the Midwest Political Science Association. {{cite journal}}: Cite journal requires |journal= (help)CS1 maint: multiple names: authors list (link) Link failed 22 January 2006.

Bennett, Scott D. (2006). "Toward a Continuous Specification of the Democracy-Autocracy Connection". International Studies Quarterly. {{cite journal}}: Unknown parameter |Issue= ignored (|issue= suggested) (help); Unknown parameter |Page= ignored (|page= suggested) (help); Unknown parameter |Volume= ignored (|volume= suggested) (help)

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Brown, Michael E., Sean M. Lynn-Jones, and Steven E. Miller. Debating the Democratic Peace. Cambridge, MA: MIT Press, 1996. ISBN 0262522136.

Cederman, Lars-Erik (2001). "Back to Kant: Reinterpreting the Democratic Peace as a Macrohistorical Learning Process". American Political Science Review (95, 1 March 2001).

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Gleditsch, Nils Petter. Christiansen, Lene Siljeholm. Hegre, Håvard (2005). "Democratic Jihad? Military Intervention and Democracy" (PDF). Paper prepared for the 45th Annual Convention of the International Studies Association, 17–20 March 2004. {{cite journal}}: line feed character in |journal= at position 53 (help)CS1 maint: multiple names: authors list (link)

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Hegre, Havard. 2000. “Development and the Liberal Peace: What does it Take to Be a Trading State?” Journal of Peace Research 37 (January 1):5–30.

Hegre, Håvard (2003). "Disentangling Democracy and Development as Determinants of Armed Conflict (required)" (PDF). Presented at the Annual Meeting of the International Studies Association.

Hermann, Margaret G. (1996). "Ballots, a Barrier Against the Use of Bullets and Bombs: Democratization and Military Intervention". Journal of Conflict Resolution. 40 (3): 436–460. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help); Unknown parameter |month= ignored (help)

Hermann, Margaret G. (1998). "The U.S. Use of Military Intervention to Promote Democracy: Evaluating the Record". International Interactions. 24 (2): 91-114. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help); Unknown parameter |month= ignored (help)

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External links

Supportive

• Rummell's website
• Spread of Democracy Will Make World Safer, Historian Says a moderated webchat with Victor Davis Hanson hosted by the Department of State, International Information Program.
• Correlates of War project hosts datasets of quantitative data in international relations.
• "Parliamentary Control of Security Policy" (paks) Parliamentary Control of Military Security Policy in the EU-25 and the Iraq War 2003. A DFG funded research project at the Heinrich-Heine-University Düsseldorf, Germany

Critical

• The Myth of Democratic Pacifism
• The Missing Democratic Peace

See also

• The End of History
• International relations theory
• Never at War
• Peace
• Perpetual peace
• War
• World peace