Today at dusk across Syria, a tenuous calm settled in even in the country's most war-torn corners. This evening's cease-fire happens to coincide with a key holiday in the Muslim world, Eid al-Adha, and the break in violence was heartily welcomed. But even amid relief, Syrians and the warring parties in the country's yearslong civil war have ushered in the long-awaited deal with great apprehension. Though the cease-fire was the product of 10 months of painstaking negotiations among numerous stakeholders, primarily the United States and Russia, previous negotiated lulls in the Syrian civil war have quickly fallen apart. This reality hung over the Sept. 10 announcement of the deal between Moscow and Washington, further benefits of which rest on the tenacity of the truce. If the cease-fire begun this evening does not hold over the next seven days, it is largely back to the drawing board, creating even further delay on any discussions over Syria's future. And it is this very fact that might mitigate some stakeholders' support for the cease-fire.
Rumors emerged in June of the U.S. offer to coordinate its actions in Syria with Russia, and the two spent the weeks since haggling over details, including the status of rebel groups such as Ahrar al-Sham and plans to separate Jabhat Fatah al-Sham — formerly known as Jabhat al-Nusra — from other rebel units. The information leaked in late June also failed to clarify whether the United States would insist on creating corridors through which humanitarian aid could reach besieged areas. (Flows of food and medicine would make it more difficult for loyalist forces to use the siege tactics they have relied on to starve out rebel pockets across the country.) The Russian-backed loyalists were also unwilling to strike a deal with the United States until they had encircled the rebel-held areas of eastern Aleppo city, a maneuver they recently accomplished after beating back a rebel counteroffensive.
Now that Aleppo has been surrounded, Moscow has agreed to Washington's proposal, although the final deal is skewed in Russia's favor. The nationwide cease-fire has taken effect between loyalist and rebel forces, with the exception of groups such as Jabhat Fatah al-Sham. Should the relative calm hold for a week, the U.S. military will then begin coordinating its bombing campaign against Jabhat Fatah al-Sham with Russia, and strict constraints will be placed on the Syrian air force's operations. The rebels, meanwhile, are expected to dissociate themselves from the group, no small task as Jabhat Fatah al-Sham is marbled throughout the country, embedded in and within other rebel forces. This is not to mention that a true break with Jabhat Fatah al-Sham would be highly unpopular with the rebel rank-and-file. Many rebels have bled and died alongside Jabhat Fatah al-Sham's fighters in countless campaigns. Rebels might make a bid to buy more time for the difficult process of dissociation — if they even decide to do so.
Given the loyalists' severely degraded control over numerous nominally aligned militias and armed groups, infractions in this week's fragile cease-fire are all but guaranteed. The Russian- and Iranian-backed loyalist troops, however, will likely abide by the agreement. In fact, though several major rebel groups have yet to accept the accord, the Syrian government, Iran and Hezbollah have announced their support for it. Their cooperation is hardly surprising: By allowing the United States to defeat the rebel groups excluded from the agreement — which also happen to be some of the most effective in the rebel coalition — loyalist forces can drive a wedge between the rebels without having to fight the bulk of them, freeing up troops to combat the Islamic State in the meantime. Once Jabhat Fatah al-Sham and groups like it are destroyed, the loyalists can then shift their attention to the substantially weakened rebel coalition.
For this reason, the rebels, unsurprisingly, have responded much differently to this weekend's U.S.-Russia deal. Perhaps the most important reactions to notice are those from groups that are neither supported nor targeted by the United States, including powerful factions such as the Turkish- and Qatari-backed Ahrar al-Sham and the Saudi-backed Jaish al-Islam. If these groups heed Washington's call to distance themselves from Jabhat Fatah al-Sham, the U.S. gambit will gain significant traction, isolating the group and making it easier to target. But the prospect of this happening is unlikely, and already Ahrar al-Sham has expressed its hesitancy about the deal.
Furthermore, Saudi Arabia and Qatar — which are already suspicious of Washington's plans in Syria — would resist any moves the United States might make to punish rebel groups that refuse to break with Jabhat Fatah al-Sham. The nonaligned rebels may pay lip service to the deal to avoid embarrassing their foreign patrons, but it will be exceedingly difficult to separate them from Jabhat Fatah al-Sham in an effective way. And if a rift forms among the Syrian opposition's external backers, it could undermine the United States' ability to influence what weapons are sent to which rebel groups. The rebel coalition's leaders are aware that the United States' strategy will cripple the rebellion as a whole.
Turkey will likewise try to prevent the United States from directly engaging rebel groups such as Ahrar al-Sham, a faction that Ankara has worked with extensively that may not divorce itself from Jabhat Fatah al-Sham. But the U.S. bargain with Russia will also create an opening for Turkey to ramp up its operations in northern Aleppo province against the Islamic State and Kurdish People's Protection Units. After all, rebels from Free Syrian Army factions that adhere to the cease-fire with the loyalists could be deployed to aid Ankara's efforts, instead.
That said, Moscow and Washington hold limited influence over some of the key players on the Syrian battlefield, which will reduce the agreement's effectiveness overall. Russia will be able to ensure the cooperation of Iran, the Syrian government, Hezbollah and other loyalist fighters. A meeting tomorrow in Moscow between Iran's deputy foreign minister for Arab and African affairs and his Russian counterpart displays the seriousness of their accord. The visit also comes as the Kremlin is trying to get Tehran to warm up to its use of the Hamdan air base, a useful display of Russian influence in the Middle East. For its part, the United States will have a hard time persuading many rebel groups to hold up their end of the bargain. And as the rebels become increasingly alarmed by a deal that will weaken their position against the Syrian government in the long run, they will challenge it more and more.
At the very least, the deal between the United States and Russia will temporarily reduce violence in Syria. The halt of indiscriminate aerial bombing and the delivery of aid to besieged areas, in particular, will bring a welcome measure of relief to the country's battered population. If in fact this week's cease-fire holds, and joint targeting begins, the next phase of peace negotiations will loom on the horizon.