- As Syrian rebels backed by Turkey advance toward al-Bab, they risk igniting a conflict with Kurdish fighters making a last-ditch effort to link the Afrin and Kobani cantons.
- Clashes between the rebels and Kurds will throw a wrench into U.S. plans to recapture Raqqa from the Islamic State.
- The chances of the Syrian conflict escalating will grow as the rebels, bolstered by Turkish and U.S. aid, draw closer to Russian- and Iranian-backed loyalists positioned just south of al-Bab.
Syrian rebels, with the help of the Turkish military, are slowly making their way across northern Aleppo province. As the rebels draw closer to the strategic city of al-Bab, their progress is wreaking havoc on the plans of the Syrian civil war's other participants. Kurdish and loyalist fighters — as well as the United States, Russia and Iran — will be forced to rethink their strategies as the risk of conflict with the advancing rebels rises.
Turkey's primary objective in launching its offensive into Syria, known as Operation Euphrates Shield, was to block the path of Kurdish forces trying to form a link between their holdings in the Afrin and Kobani cantons. And by all appearances, Turkey is on the verge of succeeding. Over the past few days, Ankara's rebel allies have capitalized on their decisive victory against the Islamic State in Dabiq by driving even farther south. As they have, the chances that the Kurdish People's Protection Units (YPG) could join the two cantons together have grown slimmer.
Galvanized by their diminishing prospects, the YPG and its allies struck out to the east, crashing headlong into the advancing rebel forces on Oct. 19. Turkey immediately targeted the Kurdish fighters with heavy shelling and airstrikes, which Ankara claims killed as many as 200 fighters. Skirmishes between the Turkish-backed rebels and the YPG have continued ever since, underscoring the deeply rooted animosity that exists between them in spite of their shared campaign against the Islamic State. With the fate of al-Bab — both a crucial crossroads in the Syrian conflict and the last link between the Afrin and Kobani cantons — at stake, the two could find themselves battling each other more than their common enemy in the weeks ahead.
A Danger to the Loyalists' Aleppo Operation
Turkey's central objectives in Syria may be to beat back Islamic State and Kurdish forces, but the rebels it supports have another goal in mind. They have not forgotten their original purpose: countering Syrian President Bashar al Assad's government. As of now, the best way for them to do that is to march south to link up with their comrades around northern Aleppo. In fact, the rebel groups participating in Operation Euphrates Shield have made it clear that they intend to resume their fight against loyalist troops once they have dealt with the Islamic State and the YPG.
The rebels' steady approach from the north is a growing concern for al Assad's forces, who are deeply engaged in a critical battle for Aleppo city. Though Turkey wants to avoid being drawn into a direct confrontation with those forces' backers, Russia and Iran, neither Moscow nor Tehran has any guarantee that Ankara will be able to control the rebels and prevent them from pushing closer to Aleppo city. Of course, Turkey is not the only party that wishes to avoid conflict. A scuffle with Turkey would hinder Russia's ability to extract itself from the Syrian conflict and would increase Russia's risk of clashing with the U.S.-backed forces supporting the rebel offensive in northern Aleppo province.
Nevertheless, Russia and Iran will have to take into account the mounting danger that the Turkish-backed rebels present. Broadly speaking, there are two ways that Moscow and Tehran could try to mitigate the threat. The first would be to bolster the YPG's eastward advance in the hope that the Kurds will form a buffer between the rebels and Aleppo city. Considering Turkey's numerous incentives to stall the Kurds' progress, though, this approach would probably only encourage Ankara to ramp up its support for the rebels as they fight their way through YPG lines. Alternately, Russia and Iran could aid loyalist troops as they move toward al-Bab. The risk of clashing with the rebels would remain high, but they would not be able to get near Aleppo city, particularly since Turkey would be eager to restrain them for fear of being pulled into a fight with Russia or Iran. Given the loyalists' heavy commitment to the battle for Aleppo city, however, assembling the force needed to push north to al-Bab would not be easy.
A Success and Setback for Washington
In a sense, the rebels' advance across northern Syria is a boon for the United States. The rebels are ousting the Islamic State from several key towns and villages as they go, depriving the extremist group of its access to a highly coveted source of recruits and taxes. In fact, this explains why the United States continues to be so heavily involved with the rebels alongside Turkey, embedding special operations forces within their ranks and providing them with air support.
That said, the rebels' progress has also complicated Washington's plans in Syria. The United States is trying to marshal a sizable local force to retake Raqqa from the Islamic State — a force that includes a large Arab component within the Syrian Democratic Forces. But those forces are predominantly composed of Kurdish fighters who belong to the YPG, which has been distracted by its counterpart clashes with Turkish-backed rebels in northern Aleppo, as well as by Turkey's persistent threats to overrun its positions in Manbij and Tal Abyad. Because of these conflicts, the YPG's ability to focus on a Raqqa offensive will be limited.
Meanwhile, as the rebels move closer to Aleppo city, the United States risks being dragged into a fight it has long tried to avoid. Should the rebels and loyalist troops set their sights on each other, the attention being paid to combating the Islamic State would undoubtedly decrease. It could also trigger a wider conflict between the United States and Russia or Iran. U.S. President Barack Obama's administration has already gone to great lengths to dodge such a clash, as evidenced by its latest failed cease-fire with Moscow, and it will not be eager to wade into any major diplomatic spats as Obama's time in office winds down.
Northern Aleppo is quickly becoming one of the most crucial theaters of the Syrian civil war. The rebel advance is not only hurting the Islamic State and hamstringing the Kurds, but it is also impeding U.S. efforts to seize Raqqa and loyalists' attempts to retake Aleppo city. Perhaps most important, though, Operation Euphrates Shield carries the risk of starting a brawl with Turkey and the United States on one side and Russia and Iran on the other — a fight whose consequences would reach well beyond Syria's borders.