To explain recent conflicts in countries such as Syria or Sudan, observers have been quick to point their fingers at proximate causes specific to our times: the power vacuum created by the end of the Cold War offered opportunities for rebels to fill the void; the recent globalization of trade flooded the developing world with cheap arms; rising global consumer demand generated new struggles over oil and minerals; jihadist groups spread using networks of fighters trained in Afghanistan and Pakistan.

Yet such explanations miss a bigger picture. If we extend the time horizon beyond the Cold War to include the entire modern period -- from the American and French revolutions to today -- we can see repeating patterns of war and conflict. These patterns are related to the formation and development of independent nation-states.

Until the eighteenth century, empires, dynastic kingdoms, tribal confederacies, and city-states governed most of the world. This changed when nationalists introduced the notion that every “people” deserved its own government. They argued that ethnic likes should rule over likes. In other words, Slovaks should be governed by Slovaks, not the House of Hapsburg; and Americans by Americans, not the British crown. Over the past two centuries, in wave after wave of nation-state formation, this new principle of political legitimacy transformed the world.

In most places, two distinct phases of conflict accompanied this transition: first, violence related to the creation of the nation-state itself, and second, an often bloody struggle over which ethnic or national groups would hold power in the newly established state, and over where the country’s final borders would settle.

BLEEDING BORDERS

Roughly a third of present-day countries have fought violent wars of independence that united, if only temporarily, the diverse inhabitants of colonial or imperial provinces against their overlords. But many of the resulting nation-states endured even worse violence after independence was won because the like-over-like principle bred further conflict among the victors themselves.

Imperial governments had often recruited members of specific minorities into the colonial army and bureaucracy. (The classic example was the Belgian preference for Rwanda’s Tutsi minority over its Hutu majority to staff the country’s colonial administration.) In other former colonies, the elites of the more assimilated and educated groups controlled the post-imperial state’s nascent bureaucracies and security apparatuses, a fact that other groups resented as a break with the like-over-like principle. More important, many new governments lacked the political power and resources to reach out to the entire population and overcome colonial-era inequalities. This made nation building more difficult and ethnic patronage more likely. Large segments of the population thus remained politically marginalized.

Whatever its origins, ethnopolitical inequality was perceived as a scandal once nationalism had been accepted as the guiding principle of legitimacy. This made it easier for opposition leaders to mobilize followers and stage armed rebellions against exclusionary regimes. Data from every country in the world since 1945 demonstrates a tight correlation between such inequality and conflict: an increase in the size of the politically excluded population by 30 percent increased the chances of civil war by 25 percent. Almost 40 percent of independent countries today have experienced at least one ethnopolitical rebellion since World War II. It is important to note that these countries are not more ethnically diverse than those at peace. It is therefore not diversity per se, but political inequality, that breeds conflict.

Of course, other factors play a role as well, including the repressive capacity of the state: After all, it is much harder to organize a guerrilla army in northern China than in Somalia. Civil wars are also more likely to break out in poorer countries where it is more economically important to have connections to the government. Finally, not all politically marginalized ethnic groups have an educated leadership capable of forming a political movement or staging a rebellion.

New nation-states are also more likely to go to war with each other than established empires or dynastic states were. Empires drew loose and often arbitrary borders with little regard to ethnicity. Nation-states, on the other hand, care more about borders because these may divide a single national group across various states. This creates the risk that those who end up on the wrong side of the border are treated as second-class citizens in neighboring states dominated by other ethnic groups -- another way that the like-over-like principle can be violated. Conflict between neighboring nation-states thus often erupts over territories where ethnic groups overlap or over borders that divide a single ethnic group. In the early 1990s, for example, the Serbian minority resisted integration into the newly founded state of Croatia. The government of Serbia, expecting that their co-ethnics in Croatia would be mistreated (and in pursuit of its own national unification project), intervened on their behalf. War between the two states followed, ending with the expulsion of the Croatian Serbs across the border.

The domestic struggle over who “owns” a new state does eventually come to an end -- on average, after sixty years. It often comes violently, by way of expulsions, population exchanges, or forced assimilation that result in a more homogenous country. In other cases, strong central governments and well-established civil society organizations have made ethnicity irrelevant to the formation of political alliances (as in Switzerland) or encouraged voluntary assimilation into the core group (as in France and Botswana). In other instances, a power-sharing arrangement between the representatives of politicized ethnic groups helps to avoid future civil war (as in Canada).

MINORITY REPORT

In short, the spread of the like-over-like principle and the formation of nation-states have been driving forces behind civil and interstate war -- a fact woefully missing from much of the popular debate about the violent conflicts of today.

Take Syria, whose history of conflict conforms closely to the pattern. The Arab uprising against Ottoman rule during World War I did not lead to the country’s independence but instead to another round of colonial domination by France. After a series of failed anticolonial rebellions during the mid-1920s, Syria finally gained independence from France at the end of World War II. Much of the political turmoil in the postcolonial period concerned the distribution of political power among ethnic elites. After a number of coups, the al-Assad clan and its small Alawite sect emerged as the new owners of the state.

Syria thus became a classic example of an ethnocracy – where an ethnic minority dominates the entire state apparatus. As a consequence of this departure from the like-over-like principle, the government utterly lacks popular support and political legitimacy. The regime compensated by adopting pan-Arab rhetoric and anti-Israel policies, accommodating the Sunni economic elite, building a massive security apparatus that penetrated the entire fabric of society, and brutally suppressing any form of protest or rebellion, such as the Sunni uprising of 1982. Now, Syria’s civil war is increasingly being fought along religious and sectarian divides, as was the case in neighboring Iraq after the U.S. invasion. Although the future remains unpredictable, it is safe to say that no durable peace will be achieved until the ethnocratic regime under Assad gives way to a power structure that integrates the country’s Sunni majority. The Kurds, meanwhile, may perhaps end up in a Kurdish state sometime in the future.

Sudan has followed a similar path. A decades-long nationalist war finally led to the secession in 2011 of southern Sudan, where non-Muslims of African descent form the majority, from northern Sudan, which has been politically dominated by Muslim Arabs since its inception. Tensions between the two states run high over the exact demarcation of the boundary between them. In its present form, the divide leaves tens of thousands of non-Muslim Africans politically marginalized in North Sudan. In South Kordofan and the Blue Nile area, which are on the northern side of the demarcation, former fighters for an independent South have continued to attack northern troops with tacit support from the newly established South Sudanese government and army. Clashes between the two states’ militaries have led many analysts to fear more violence in the future.

In the South, ethnopolitical inequality has led to domestic conflict as well. Shortly after independence, new complaints arose about the dominance of former Dinka fighters, who had founded and controlled the independence movement, in the recently formed bureaucracy and army. Armed conflicts erupted between government forces and various rebel factions claiming to represent Nuer or Murle constituencies.

What will the future bring for the two Sudans? Given that control over significant oil resources is at stake, their conflict is unlikely to be settled through a simple redrawing of boundaries. It is equally improbable that the current government in Khartoum will open its ranks to former independence fighters and their ethnic followers. A long-lasting, low-intensity conflict is far more likely -- at least as long as the ethnocratic regime in Khartoum survives. As for the domestic conflict in South Sudan, given the state’s low institutional capacity, it will be difficult to pursue a successful nation-building project by integrating the country’s various ethnic constituencies and depoliticizing tribal and ethnic allegiances. One can expect that jostling for power in unstable coalitions and occasional infighting will continue.

Kosovo also conforms to the pattern. It became a sovereign country after decades of nationalist mobilization against alien rule by the Serbian state. The independence war of the late 1990s led to NATO intervention, followed by a decade of UN administration. In 2008, Kosovo was declared sovereign. Tensions between the young state’s Albanian majority, empowered by independence, and its Serbian minority still run high. Without NATO protection, these Serbian enclaves would probably have been ethnically cleansed a long time ago. And if Serbia had not been under the threat of further NATO bombings, it most likely would have intervened militarily to protect its ethnic brethren across the border, bringing the two states to war. Intervening relatively early, then, can help prevent such conflicts from escalating to the level of full-scale war seen in Bosnia. The Bosnian episode also illustrates, however, that it is not a sustainable solution to force elites with opposing nationalist agendas to share power in a state they do not want.

This historical pattern is not without exceptions. Nor does it explain all of the wars in the world. Some ethnically heterogeneous nation-states, including Montenegro, have emerged without violence and have remained peaceful. Some of the most intractable conflicts have erupted in such long-established nation-states as Colombia and have nothing to do with nationalism or ethnicity. Still, far more examples could be cited that do follow the pattern: Think of the Kurdish struggle in Turkey, the shaky peace process in Northern Ireland, the Darfur drama, the sectarian violence still haunting Iraq, the series of Caucasian conflicts that have emerged since the dissolution of the Soviet empire, or resistance to Chinese rule in Tibet. More complicated cases are those in which ethnopolitical exclusion has led to a guerilla movement with a non-ethnic agenda, such as the Marxist fighters in Guatemala, or the Maoist ones in Peru, Nepal, and parts of India.

One can reasonably predict, then, that contemporary states that politically marginalize large portions of their population might well descend into protracted armed violence. A number of countries are at risk, including Rwanda, where a small group of Tutsi returnees from neighboring Uganda rules over the Hutu majority with an iron fist; Jordan, which might one day no longer be able to divert the political aspirations of its large, politically powerless group of Palestinian citizens to neighboring Israel; Peru and Guatemala, which, unlike Bolivia, continue to marginalize their large indigenous populations; and Guinea, where the party favored by the ethnic Peul, who make up roughly 40 percent of the population and have long been excluded from power, has protested rigged elections as recently as February.

These enduring patterns of violence demand policy solutions that sound simple in theory but are deeply challenging to put into practice. Building more inclusionary power structures -- not necessarily through electoral democracy -- represents the most viable strategy for new states to prevent armed conflict. Macedonia is often cited as a successful example of how institutional engineering, under intense international pressure, can lead to a relatively stable power-sharing arrangement. One can enlarge the list of successful strategies by calling attention to Tanzania, where a dominant nationalist leader built a far-reaching infrastructure of power that bridged ethnic divides. Botswana and Burkina Faso also provide examples of successful ethnic inclusion -- in the case of latter, thanks to a strong network of trade unions that provided a platform for ethnic political integration. At the same time, the recent U.S. experience in Afghanistan shows just how difficult it is to foster political integration through occupation. Outsiders who provide public goods -- schools, hospitals, and the like -- undermine the legitimacy of the domestic government, rather than foster it. Nation building from the outside, then, is not just difficult but structurally impossible. The path to peace -- toward an inclusionary state that does not violate the like-over-like principle -- begins at home.