A woman and children watch an anti-Assad protest from a balcony in Aleppo. (Muzaffar Salman / Courtesy Reuters)

In a recent piece on ForeignAffairs.com, Bilal Saab and Andrew Tabler resurrected a marginal debate from the 1990s about the dangers of negotiated settlements to civil wars. After making a general case against negotiated settlements, they applied their logic to Syria. The historian Edward Luttwak made the same basic argument 15 years ago. Negotiated agreements, he explained, preserve actors' war-making capacities, which leads to security dilemmas and, inevitably, renewed bloodshed. The policy prescription: Let the two sides fight it out until one wins. Either way, a more durable, longer-lasting peace should follow. The argument was wrong 15 years ago and, as recent data show, continues to be wrong today.

Saab and Tabler's central claim is that "[n]egotiated settlements have, in fact, proved weak in terms of promoting mutual disarmament, military integration, and political powersharing." That claim runs contrary to existing data. For example, Anna Jarstad and Desirée Nilsson, researchers in the Department of Peace and Conflict Research at Uppsala University, in Sweden, have found that, between 1989 and 2004, 75 percent of political powersharing provisions were implemented after an accord was reached -- most within a period of seven months. Jarstad and Nilsson also found that 90 percent of military integration provisions were at least partially implemented. Their statistical analysis revealed that, where military integration is implemented, a relapse of armed conflict is very unlikely. Our own research, meanwhile, has shown that disarmament provisions in peace agreements are implemented over 70 percent of the time.

Saab and Tabler also write that "[l]ess than a quarter of all civil wars since 1945 have ended in a negotiated settlement," leaving the reader with the overall impression that negotiated settlements are scarce. Such a claim conceals perhaps the most significant trend in global conflict in decades: the sudden and dramatic increase in the last 25 years in the proportion of civil conflicts ended by peace agreements. During the Cold War, about 20 percent of civil wars ended in a settlement. That number is around 60 percent today, and even higher if minor civil conflicts are included in the calculation. Since 1989, combatants in civil conflicts have reached about 180 peace agreements, according to Uppsala University's conflict data program.

In fact, the option that Saab and Tabler seem to present as the most credible for ending the war in Syria -- a decisive military victory by the rebels -- is the rarest. According to data compiled by Joakim Kreutz, an assistant professor at Uppsala University, there have been 18 rebel victories since 1989. The majority of rebel victories were achieved within the first year of combat (Syria's civil conflict is going into its third year). Furthermore, when the rebels do win, it is rarely a decisive military outcome. A closer examination of the 18 rebel victories reveals that six were military coups where there was no real domestic insurgency. Of the remaining 12, seven occurred in failed or failing African nations: one in Haiti and three of the remaining four in Afghanistan. The larger point is that most rebel triumphs result from an impending government collapse, rather than a defeat of government forces.

In Syria, if the rebels were going to achieve a decisive military victory, they would have done so by now. The real options left there are quite narrow. The Alawites, the religious minority loyal to President Bashar al-Assad, are also not likely to achieve a military victory. Even if they were able to defeat the rebels, it would be a temporary lull. Instead, leaders in Damascus could offer amnesty to the rebels to initiate negotiations for a formal cease-fire, which would include international monitoring and peacekeeping troops. That would create the space to begin a slow, deliberate process of formal mediation that addresses all of the major conflict issues. Mediation ought to involve third parties and all the major factions of the opposition. Of peace agreements that have met those conditions, less than five have failed in the last 25 years.

The goal of prolonged mediation should be a final agreement, built upon previous ones, in which inclusiveness and broad institutional reforms are the goal. Civil war data and current conflict trends predict that the Syrian conflict will end in a negotiated settlement. The only choice is whether it will be soon, leaving Syria largely intact, or later, when even more of the country is in ruins.