The Syrian civil war, now approaching its seventh year, is a proxy war many times over. A fragmented opposition, long backed by outside powers, is continuing to fight the regime of Syrian President Bashar al-Assad, itself propped up by Iran, Russia, and Hezbollah. Turkey, a NATO ally, not only supports rebel factions but has recently invaded part of northwestern Syria in order to wrest the canton of Afrin from Kurdish control. The Kurds—the most reliable troops in the fight against the Islamic State (ISIS)—are in turn backed by the United States. And on February 10, Syrian forces shot down an Israeli F-16 after an Iranian drone penetrated Israeli airspace. Despite multiple attempts to negotiate an end to hostilities, the level of foreign involvement in Syria means that the war will not cease until external actors decide that it should.

Although particularly complex, the Syrian civil war is an example of a general trend: civil wars are lasting longer and are increasingly likely to end with a one-sided victory rather than a negotiated settlement. This follows a brief period, from the fall of the Berlin Wall until the 9/11 attacks, when, for the first time in history, most civil wars ended in negotiation. What changed to account for these trends?


The course of civil wars is influenced by the international political environment. A given environment has specific norms, or expectations of appropriate behavior, that influence the decisions of policymakers. This is true for conflict resolution as well: in different periods, policymakers have different beliefs about how conflicts—including civil wars—ought to end, which in turn affects how they do end. 

Turkish soldiers near the Turkish-Syrian border, February 2018.
Umit Bektas / Reuters

There have been three distinct international political environments in recent history. The first, the Cold War, lasted from 1946 to 1989 and was characterized by bipolarity between the United States and the Soviet Union. The fall of the Berlin Wall in 1989 signaled the start of the second environment—that of liberal-democratic unipolarity and U.S. hegemony. The third and current international environment arose with the attacks of 9/11 and the beginning of the war on terrorism; it features rising authoritarianism, a renewed focus on security, and increasing multipolarity.

The international political environment shapes norms about civil wars. During the Cold War, both the United States and the Soviet Union viewed civil wars as zero-sum contests in which their preferred side should pursue total victory. And indeed, this normative lens had real-world consequences. While the U.S.-Soviet rivalry lasted, it was inconceivable that civil wars in, for instance, Cambodia, El Salvador, or Mozambique could end in negotiation, given the investment of both superpowers in supporting local proxies to defeat the other. During the Cold War, civil wars ended five times more often in victory than in settlement.

With the end of Cold War bipolarity, the United States sought to build a liberal international order based on democracy and open markets. The winner-take-all, zero-sum norms of the Cold War gave way to a search for positive-sum solutions. In the context of civil wars, although the United States and its allies could ensure victory for their preferred side, they instead sought to broker negotiated settlements as a path toward post-conflict democratization.

The Syrian civil war is an example of a general trend: civil wars are lasting longer and are increasingly likely to end with a one-sided victory rather than a negotiated settlement.

As a result, during this era many wars that could have ended in one-sided victory did not. Take the conflict in Bosnia. In the summer of 1995, Bosnian Serb forces were on the brink of defeat by the NATO-backed army of the Muslim-Croat federation. The Serbs’ historical outside ally, Russia, was recovering from the collapse of the Soviet Union and no longer willing or able to oppose the United States or NATO. But rather than allow the defeat of the Bosnian Serbs, Washington called off its allies’ advance and pushed instead for a negotiated compromise at Dayton. Most civil wars in this period similarly ended in some sort of negotiation. 

After 9/11, however, the environment shifted again, as did prevailing norms. The United States was suddenly faced with the threat of international terrorism and challenges to its hegemony by a rising China and, more recently, a reassertive Russia. Although the norm of negotiation has not died, countervailing norms have emerged around non-negotiation with terrorists, militarily defeating terrorist organizations, and prioritizing stabilization over democratization, even if that means bolstering authoritarian rule.

Across today’s battlefields—in the Central African Republic, the Democratic Republic of Congo, Libya, Mali, Myanmar, the Philippines, South Sudan, and Yemen—external actors are again fueling different sides of civil wars with the aim of helping one side win outright. Governments paint rebels as terrorists in an effort to legitimize their pursuit of complete victory, and to solicit support from outside powers. Such strategies would not have been so widely accepted during the 1990–2001 era of democratization. In conflict zones and civil wars, it is now legitimate to try to defeat groups labeled as terrorists and to promote authoritarian rule in the name of stability.


The Syrian civil war is thus a typical, if unusually brutal, example of a contemporary civil war. More than 400,000 people have been killed, 5.5 million have fled the country, and six million have been internally displaced. The UN estimates that at least 13 million Syrians are currently in need of humanitarian assistance—more than half the prewar population of 22 million.

The war has endured in large part because of external actors, many of them committed to achieving zero-sum victory within the context of a regional power struggle. When fighting erupted in late 2011 and early 2012 in response to the government’s violent repression of protests, opponents of the Assad regime, such as the Gulf states and Turkey, were quick to provide weapons to the rebels, although they quickly fell out among themselves, contributing to the fracture of the opposition. Buoyed by the NATO coalition’s 2011 intervention in Libya, the United States considered armed action in Syria as well. Although U.S. President Barack Obama came close to launching a military strike in August 2013, his administration chose instead to provide aid and training to opposition groups. (Washington did finally intervene in the fall of 2014, when it began conducting air strikes, but these remained focused on ISIS while avoiding regime targets.)

A Turkish-backed Free Syrian Army fighter in Afrin, Sryia, February 2018.
Khalil Ashawi / Reuters

Iran, too, moved early in the conflict to provide support to Assad, its most important ally in the region. Tehran deployed several thousand of its own soldiers to Syria, to join troops from its regional proxy, Hezbollah, and helped the regime to assemble militias from tens of thousands of foreign Shiite fighters. Russia has also aided the Assad regime, including, since September 2015, through direct military intervention. Such outside support has prolonged the war by bolstering the regime every time it looked ready to collapse. As a result, the Syrian government today has consolidated its hold over territory west of the Euphrates River. If the conflict continues along its current trajectory, the Assad government is likely to reassert control over most of the country.

The United States has formally advocated a negotiated settlement to the conflict, but both the rise of ISIS in 2014 and the increasing prominence of jihadist groups within the Syrian opposition have pushed Washington toward a de facto, tacit acceptance of the authoritarian Assad regime. Today, the United States and its allies are mostly concerned with the limited goal of destroying terrorist networks. The language of stability and counterterrorism has replaced the language of democracy. In January, for instance, U.S. Secretary of State Rex Tillerson emphasized the importance of ensuring that Syria “never again serves as a platform or safe haven for terrorists.” 

Negotiations continue: Iran, Russia, and Turkey have opened a track of international talks that run parallel to the UN and U.S.-backed Geneva process, and in January, Russia hosted peace talks in Sochi aimed at drafting a new Syrian constitution. But so far, external actors have only been able to ensure the near-territorial defeat of ISIS, broker brief cease-fires among other warring factions, and establish short-term measures to stabilize the conflict and provide some humanitarian support to civilians. Indeed, outside powers have undoubtedly prolonged the war by supporting opposing sides and failing to coalesce around the goal of a negotiated settlement leading toward regime change and democratization, as they might have in the decade after the Cold War. Instead, they have come to expect a one-sided victory for Assad, rendering that outcome more likely.


Syria’s seemingly endless civil war illustrates the norms of the current international environment in action: the retreat of a liberal United States and its allies, who no longer have the interest in pushing through a negotiated settlement; a focus on counterterrorism that has driven outside powers to prioritize the fight against ISIS; and a new emphasis on stability that has led the United States and others to tacitly accept the authoritarian Assad regime (or its successor) as the eventual victor and guarantor of security. Civil wars tend to end the way that external actors think they should end. As with most civil wars, the one in Syria will end according to the normative ideas of external actors. In the current environment, that probably means victory for Assad.

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  • LISE MORJÉ HOWARD is Associate Professor in the Department of Government at Georgetown University and ALEXANDRA STARK is a Ph.D. Candidate in the Department of Government at Georgetown University. They are the authors of "How Civil Wars End: The International System, Norms, and the Role of External Actors."
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