Do Ceasefires Ever Work?

Earlier this week, the Syrian government, the Free Syrian Army, and other rebel elements agreed to a temporary, four-day ceasefire for the Muslim holiday of Eid al-Adha.

Even before it went into effect, one opposition group, Jabhat al-Nusra, had publicly disavowed the ceasefire, and on its first morning there were reports of clashes between rebel and government forces in Aleppo and Damascus. A car bomb also exploded in the capital city, resulting in multiple casualties. Still, neither side has formally declared the ceasefire dead as of yet, and early reports suggest that the fighting does seem to be somewhat reduced.

What are the prospects for this temporary ceasefire? And what are the prospects for a more permanent ceasefire in Syria?

Temporary ceasefires bring temporary relief from the day-to-day grind of war — and for residents of battered cities like Aleppo, even a few days of relief over an important holiday will be welcome. Even an imperfectly respected ceasefire can bring some respite if the level of violence drops significantly.

Beyond that, it’s possible that a temporary ceasefire or lull could build a sliver of trust and momentum toward a permanent end to hostilities. If both sides are serious about making a deal, a temporary lull in violence this weekend could provide an opening for negotiations. But that’s a big if.

If the ceasefire hasn’t already been derailed by Friday morning’s clashes, what are the prospects for a more permanent peace deal? Wars end in negotiated deals when the costs of continuing to fight outweigh the prospects for winning. The war has proved costly for both the rebels and the government (and, of course, for the Syrian people — but unfortunately, it’s not up to civilians whether the war continues or not). Bashar al-Assad’s government is isolated internationally and has not been able to crush the challenge to its rule. It is unlikely the Syrian Army will be able to quell the rebellion without extreme measures — measures that even Assad’s most stalwart international friends might not be able to stomach. The rebels, too, are a very long and costly slog from any prospect of toppling the regime. Without a peace agreement, both sides must know they face a difficult path toward, at best, uncertain victory.

In such a mutually painful status quo, bargaining theory tells us that negotiation should be preferable to continued violence. But reaching a deal and committing to it credibly is no easy task. Even if both sides are serious about negotiating a peace deal, and see some prospects for overcoming the commitment problem, would a temporary four-day holiday ceasefire help move the process forward? If the current violence subsides and the main parties abide by the ceasefire, it could build trust on both sides. But if the ceasefire fails entirely and full-scale fighting resumes, the opposite holds true.

The temporary ceasefire plan negotiated by U.N. envoy Lakhdar Brahimi faces obstacles. All ceasefires are fragile, but temporary ones face a structural problem that makes them more fragile than most. As the end of the ceasefire period nears, there is an incentive to go on the offensive prior to the expiration date in order to gain an advantage over the other side. The other side is aware of this, however, and has an equal incentive to move against its adversaries, who, in turn, know this, and so have an incentive to attack even sooner, and so on and so forth. Not surprisingly, temporary ceasefires with a fixed expiration have a tendency to unravel.

This problem can be mitigated if both sides know that it would be clear who broke the ceasefire first — provided there are real costs to doing so. In this case, the Syrian government is probably hoping to use the ceasefire, and its willingness to agree to it, to shore up international support, and so it will not want to be blamed for being the first to break the ceasefire. And to the extent that the rebels hope to maintain the sympathy of most of the outside world (and the possibility of intervention on their behalf), they also have an incentive not to be seen as violating the truce first. (Of course, rebel elements like Jabhat al-Nusra have already demonstrated that they aren’t swayed by international opinion.) But this is a do-it-yourself ceasefire — there will be no monitors to observe compliance, since the U.N. withdrew its observer mission over the summer. As a result, if fighting resumes, it will be difficult for outsiders to tell who started what. The military incentives to strike first, coupled with plausible deniability, thus make it less likely that the truce will hold through the holiday weekend.

If fighting starts again with a vengeance before the holiday weekend is over, the failure of the temporary truce may do more harm than good by shattering whatever sliver of trust that reaching the agreement has generated, which might then hamper future negotiations. The more failed attempts at peace in the past, the harder it is to work toward negotiated peace in the future.

But if ceasefires are inherently fragile, that doesn’t mean they can’t be made more durable. Both the commitment problem that makes ending wars so difficult and the problem of deniability that results from imperfect information can be alleviated by international peacekeeping operations.

Fortunately, the U.N. is reportedly preparing contingency plans for just such a peacekeeping mission, should a more comprehensive deal be reached. Historically, we know that ceasefires are dramatically more likely to stick if peacekeepers are deployed than if belligerents are left to their own devices.

Peacekeeping missions are notoriously dysfunctional — chronically underfunded and underequipped; they tend to arrive late and are plagued by force interoperability problems. And yet, they are surprisingly effective. Why is this so? Impartial observers make it more costly to violate the terms of a ceasefire (or a more comprehensive peace deal) by providing information to the international community about who is or is not living up to commitments. They also provide the same information to the local population. So to the extent that the parties are vying for both international and domestic legitimacy, their presence makes returning to war more costly and maintaining a ceasefire more likely.

Agreeing to, and cooperating with, an intrusive peacekeeping mission also provides a costly, and therefore credible, signal from each side to the other about intentions for peace. This in itself can help alleviate mistrust between warring parties. And of course, knowing that outsiders will be watching and reporting what the other side is doing makes it easier to trust that one will not be suckered into an agreement and then caught unawares if the other side attacks.

Peacekeeping is not perfect, of course. It does not guarantee that peace will last. But it does a remarkably good job of improving the odds. Empirically, peacekeeping reduces the risk that a ceasefire will fail by 75-85 percent.

Unfortunately, there is no way to get a peacekeeping mission to Syria to observe the fragile Eid al-Adha truce, if indeed one still remains. The minimal U.N. observer mission that was dispatched last year is long gone and the international community is working, first, to get some basic humanitarian aid to Syrians amid the relative calm. Deploying a peacekeeping mission takes much longer than a weekend.

U.N. peacekeeping chief Hervé Ladsous has said the organization is planning such an operation. A peacekeeping mission would require approval from the Security Council, however, members of which have already vetoed three resolutions on Syria. However, Security Council approval is quite likely if peacekeeping is part of peace deal and is agreed to by both sides of the conflict. The Syrian government will, like most governments, be reluctant to allow peacekeepers in, and bridle at the infringement on Syrian sovereignty that will entail. But this is true of all governments on the receiving end of peacekeeping, many of whom ultimately decide it is worth it to swallow their pride and request peacekeepers as the price for durable peace. The Free Syrian Army will presumably be more amenable to peacekeeping. Depending on the composition of the mission, splinter opposition groups may be less obliging. Many countries, however, might be understandably reluctant to send military personnel to Syria, even in the context of a peace deal. Whether the mission would be mounted by the U.N., by NATO, or by an ad hoc group of interested states remains to be worked out. But a peace deal without such a mission is almost certainly doomed to failure.

The temporary truce this weekend may or may not move Syria closer to a more permanent ceasefire. But if and when one is reached, an international peacekeeping mission will be necessary to secure a durable peace in that country.