A nationwide cease-fire between Syria's loyalists and rebels took effect at midnight Dec. 29. Several rebel leaders have pledged to abide by the deal. This is the third cease-fire of 2016 and, notably, was brokered by Russia, Turkey and Iran without U.S. involvement. According to Moscow, the truce will pave the way for political negotiations to be held in the Kazakh capital of Astana. Russia has said that after the inauguration of President-elect Donald Trump, the United States may be invited to participate.
Russia, Turkey and Iran are all heavily involved in the Syrian civil war and each have their own reasons for fostering a truce. In spite of its support for the government of President Bashar al Assad, Russia is hoping to wind down its role in the conflict without becoming more deeply mired in a costly fight against the rebels and the Islamic State. Moscow believes that some sort of political settlement can allow for a graceful exit. The recent fall of Palmyra to Islamic State fighters was a chilling reminder to Moscow of the deadly extent of the work that is left in Syria before the country is stable or secure.
Turkey is eager to stop the erosion of rebel-held territory as it tries to solidify its position in northern Aleppo province. Chaos, moreover, works against the country's goal in Syria; it needs stability so it can pursue its objective of enlarging its sphere of influence in its former Ottoman domains and stunting the spread of Kurdish forces.
Iran and its Hezbollah allies are committed to securing a loyalist military victory that would shore up links to Damascus, links that will, in turn, help Iran to maintain its influence in the Middle East. The country will remain involved in the fight until al Assad's political security is assured. It has the means and motivation to spoil the cease-fire if it believes that that security is in question.
Though the truce may bring some progress in the short term, it will be difficult to maintain. (In fact, some violations have already taken place.) It does not have the support of powerful jihadist groups such as the Islamic State and Jabhat Fateh al-Sham that can influence the outcome of the civil war. (In fact, they were not even invited to participate.) Iran is not all that enthusiastic about the potential political agreement because it could involve the potential participation of its regional rival, Saudi Arabia. And Russia and Turkey — the two players most committed to the deal — have only a tenuous hold over the loyalist and rebel forces they work with the most. Without more control, they will not be able to enforce the terms of the cease-fire absolutely.