At one level the answer is obvious: an internal fight for control of a nation. But in the bloody conflicts that split modern states, our policy makers often understand something deeper to be at work. The vengeful slaughter that has ripped apart Bosnia, Rwanda, Syria, and Yemen is most often seen as the armed eruption of ancient and complex hatreds. Afghanistan is embroiled in a nearly impenetrable melee between Pashtuns and smaller ethnic groups, according to this thinking; Iraq is split by a long-suppressed Sunni-Shia feud. The coalitions fighting these wars are seen as motivated by the deepest sort of identity politics, ideologies concerned with group survival and the essence of who we are.


This view has long shaped America’s engagement with countries enmeshed in civil war. It is also wrong, argues Fotini Christia, an up-and-coming political scientist at MIT.

In a new book, “Alliance Formation in Civil Wars,” Christia marshals in-depth studies of the recent wars in Afghanistan, Iraq, and Bosnia, along with empirical data from 53 civil conflicts, to show that in one civil war after another, the factions behave less like enraged siblings and more like clinically rational actors, switching sides and making deals in pursuit of power. They might use compelling stories about religion or ethnicity to justify their decisions, but their real motives aren’t all that different from armies squaring off in any other kind of conflict.

“The idea that today’s enemy can be the next day’s friend was very compelling to me,” Christia said in an interview. “We should not be surprised to see groups switching sides, based on how the balance of power on the ground evolves.”

How we understand civil wars matters. Most civil wars drag on until they’re resolved by a foreign power, which in this era almost always includes the United States. If she’s right, if we’re mistaken about what motivates the groups fighting in these internecine free-for-alls, we’re likely to misjudge our inevitable interventions—waiting too long, or guessing wrong about what to do.


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Civil wars always have loomed large in the collective consciousness. Americans still debate theirs so vociferously that a blockbuster film about Abraham Lincoln feels topical 150 years after his death. Eastern Europe saw several years of ferocious killing in the round of civil wars that followed World War II.

Such wars have been understood as fights over differences that can’t be resolved any other way: fundamental questions of ideology, identity, creed. A disputed border can be redrawn; not so an ethnic grudge. In the last two decades, identity has become the preferred explanation for persistent conflicts around the world, from Chechnya to Armenia and Azerbaijan to cleavages between Muslims and Christians in Nigeria.

This thinking allows for a simple understanding, and conveniently limits the prospect for a solution. Any identity-based cleavage—Jew vs. Muslim, Bosnian vs. Serb, Catholic vs. Orthodox—is so profoundly personal as to be immutable. The conventional wisdom is best exemplified by a seminal 1996 paper by political scientist Chaim Kaufmann, “Possible and Impossible Solutions to Ethnic Civil Wars,” which argues that bitterly opposed populations will only stop fighting when separated from each other, preferably by a major natural barrier like a river or mountain range.

During the 1990s, this sort of ethnic determinism drove American policy toward Bosnia and Rwanda. It was popularized by Robert Kaplan’s book “Balkan Ghosts,” which was read in the Clinton White House and presented the wars in the former Yugoslavia as just the latest chapter in an insoluble, four-century ethnic feud. Like Kaufmann, Kaplan suggested that the grievances in civil wars could only be managed, never reconciled.


After 9/11, policy makers in Washington continued to view civil wars through this prism, talking about tribes and sects and ethnic groups rather than minority rights, systems of government, and resource-sharing. That view was so dominant that President Bush’s team insisted on designing Iraq’s first post-Saddam governing council with seats designated by sect and ethnicity, against the advice of Iraqis and foreign experts. It became a self-fulfilling prophecy as Iraq’s ethnic civil war peaked in 2006; things settled down only after death squads had cleansed most of Iraq’s mixed neighborhoods, turning the country into a patchwork of ethnically homogenous enclaves. Similarly, this thinking has shaped US policy in Afghanistan, where the military even sent anthropologists to help its troops understand the local culture that was considered the driving factor in the conflict.

Christia grew in up in the northern Greek city of Salonica in the 1990s, with the Bosnian war raging just over the border. “It was in our neighborhood and we discussed it vividly every night over dinner,” she says. The question of ethnicity seized her imagination: Were different peoples doomed to conflict by incompatible identities? Or were the decision-makers in civil wars working on a different calculus from their emotional followers? As a graduate student at Harvard, Christia flew to Afghanistan and tried to turn a dispassionate political scientist’s eye to the question of why warlords behave the way they do.


Christia spent years studying these warlords, the factional leaders in a civil war that broke out in the late 1970s. As a graduate student and later as a professor, she returned to Afghanistan to interview some of the nastiest war criminals in the country. She concluded that culture and identity, while important for their adherents, did not seem to factor into the motives of the warlords themselves, and specifically not in their choices of wartime allies. Despite the powerful rhetoric about ethnic alliances forged in blood, warlords repeatedly flipped and switched sides. They used the same language—about tribe, religion, or ethnicity—whether they were fighting yesterday’s foe or joining him.

If ethnicity, religion, and other markers of identity didn’t matter to warlords, Christia asked, what did? It turns out the answer was simple: power. After studying the cases of Afghanistan, Bosnia, and Iraq in intricate detail, Christia built a database of 53 conflicts to test whether her theory applied more widely. She ran regression analyses and showed that it did: Warlords adjusted their loyalties opportunistically, always angling for the best slice of the future government. It’s not quite as simple as siding with the presumed winner, she says: It’s picking the weakest likely winner, and therefore the one most likely to share power with an ally.


In this model of warlord behavior, the many factions in a civil war are less like Cain and Abel and more like the mafia families in “The Godfather” trilogy. Loyalties follow business interests, and business interests change; meanwhile, the talk about family and blood keeps the foot soldiers motivated. In Bosnia, one Muslim warlord joined forces with the Serbs after the Serbs’ horrific massacre of Muslims at Srebenica, and justified his switch by saying that the central government in Sarajevo was run by fanatics while he represented the true, moderate Islam. In case after case of intractable civil wars—Afghanistan, Lebanon, Iraq, the former Yugoslavia—Christia found similar patterns of fluid alliances.

“The elites make the decision, and then sell it to the people who follow them with whatever narrative sticks,” Christia said. “We’re both Christians? Or we’re both minorities? Or we’re both anti-communist? Whatever sticks.”

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Christia’s work has been received with great interest, though not all her academic colleagues agree with her conclusions. Critics say identity is more important in civil wars than she gives it credit for, and we ignore it at our peril. Roger Petersen, an expert on ethnic war and Eastern Europe who is a colleague of Christia’s at MIT and supervised her dissertation, argues that in some conflicts, identity—ethnic, religious, or ideological—is truly the most important factor. Leaders might make a pact with the devil to survive, but once a conflict heads to its conclusion, irreconcilable conflicts often end with a fight to the death. Communists and nationalists fought for total victory in Eastern Europe’s civil wars, with no regard to their fleeting coalitions of opportunity against foreign occupiers during World War II. More recently, Bosnia’s war only ended after the country had split into ethnically cleansed cantons.

Christia acknowledges that her theory needs further testing to see if it applies in every case. She is currently studying how identity politics play out at most local level in present-day Syria and Yemen.

If it holds up, though, Christia’s research has direct bearing on how we ought to view the conflict today in a nation like Syria. The teetering dictatorship is the stronghold of the minority Allawite sect in a Sunni-majority nation. And leader Bashar Assad has rallied his constituents on sectarian grounds, saying his regime offers the only protection for Syria’s minorities against an increasingly Sunni uprising. But Syria’s rebellion comprises dozens of armed factions, and Christia suggests that these militants, which run the gamut of ethnic and sectarian communities, will be swayed more by the prospect of power in a post-Assad Syria than by ethnic loyalty. That would mean the United States could win the loyalty of different fighting factions by ignoring who they are—Sunni, Kurd, secular, Armenian, Allawite—and by focusing instead on their willingness to side with America or international forces in exchange for guns, money, or promises of future political power.

For America, civil wars elsewhere in the world might seem like somebody else’s problem. But in reality we’re very likely to end up playing a role: Most civil wars don’t end without foreign intervention, and America is the lone global superpower, with huge sway at the United Nations. Christia suggests that Washington would do well to acknowledge early on that it will end up intervening in some form in any civil war that threatens a strategic interest. That doesn’t necessarily mean boots on the ground, but it means active funding of factions and shaping of the alliances that are doing the fighting. In a war like Syria’s, that means the United States has wasted precious time on the sidelines.

Despite her sustained look at the worst of human conflict, Christia says she considers herself an optimist: People spend most of their history peacefully coexisting with different groups, and only a tiny portion of the time fighting. And once civil wars do break out, the empirical evidence shows that hatreds aren’t eternal. “If identities mattered so much,” she says, “you wouldn’t see so much shifting around.”

Thanassis Cambanis, a fellow at The Century Foundation, is the author of “A Privilege to Die: Inside Hezbollah’s Legions and Their Endless War Against Israel” and blogs at thanassiscambanis.com. He is an Ideas columnist.