Throughout the conflict, the regime has had the strongest control over the predominantly Alawite coastal areas despite brief and isolated rebel offensives, the most recent of which took place in late March. The regime mostly has control over Damascus proper, but rebels are still entrenched in a number of rural areas surrounding the capital, undermining the regime's complete control of the province and tying up vast numbers of loyalist forces. But Aleppo is one of the areas where the regime has had the most difficulty exerting control over the past three years. While the regime and rebels continue to battle for complete control of the city, the surrounding area includes large chunks of rebel-controlled territory, and a combination of Kurds and the two al Qaeda affiliates — the Islamic State in Iraq and the Levant and Jabhat al-Nusra — control the areas in eastern Syria.
Given the current conditions, it is unlikely that the Syrian regime will be able to seize complete control over the core geographic and economic hubs within the next year. We have written extensively about the support structure that enables the regime to remain in its position of strength: the unity of the al Assad regime, Alawite control over the military-intelligence apparatus and the continued economic assistance of foreign backers and Sunni business elite. Alternatively, the rebels have stayed in the fight mostly due to foreign support, a similar ideological motivation and significant demographic support for their cause. However, should there be a mass desertion of rebels, widespread and prolonged infighting or the loss of foreign support, more lasting regime gains could be expected across the country.
The military court of the Free Syrian Army General Staff on May 7 sentenced Brig. Gen. Mohammed Abu Zaid to death in absentia for abandoning the rebel ranks and returning to the regime. The former president of the military court in Aleppo, Abu Zaid announced that he was rejoining the regime on Syrian state television April 24. News of his defection came the same week that the head of the military council in Homs and Damascus deserted — reportedly due to the dismissal of the former chief of staff of the Free Syrian Army's supreme military council — highlighting the fractured nature of the group.
There have been reports throughout the conflict of rebel groups giving up their weapons and deserting the cause, but specific examples of rebels rejoining the regime are more rare, making the latest defections notable. More of these reports could weaken rebel morale and lead to even more Free Syrian Army defections. At the same time, it has been several weeks since their defections, and there has been no evidence of follow-on desertions. Even if more Free Syrian Army fighters left, mass defections would need to take place across a wide portion of rebel forces before they degraded their capability.
Sustained and pervasive infighting could also significantly weaken rebel forces. Competition and varying degrees of infighting have always existed among the many rebel brigades, but during the first few months of 2014, intense clashes took place as rebels fought back against the Islamic State in Iraq and the Levant. In late 2013, the Islamic State in Iraq and the Levant began launching an increasing number of attacks against any rebel, regime or Kurdish group that got between it and its initiatives, making the group a target for nearly all the other rebel brigades. Amid the infighting, the regime eventually managed to solidify its gains by cutting rebel supply lines and making advances in Aleppo, Deir el-Zour and Latakia.
Continued fighting between the Islamic State in Iraq and the Levant on one side and Jabhat al-Nusra on the other dramatically escalated in Deir el-Zour in the past week. If the infighting were to reach a point where rebels across the country were more engaged in battling each other than defending their territory and launching offensives against loyalist forces, it would severely hamper the rebels as a whole. Aside from the Islamic State in Iraq and the Levant and some tensions between Jabhat al-Nusra and the Islamic Front in Daraa, however, at this point the vast majority of the rebel groups have made it clear that their first priority is bringing down the al Assad regime.
Another factor that could undermine the rebels would be the loss of financial and military support from benefactors in many Western countries as well as Saudi Arabia, Qatar, Jordan and others. Many of these foreign benefactors support a different rebel group; for example, Jordan provides weapons and funding to the southern front while the United States prefers to send aid and assistance to the Free Syrian Army. Meanwhile, many in Saudi Arabia and Kuwait are backing more radical Salafists, while the Saudi government is committed to the Free Syrian Army and cracking down on jihadists, and Qatar is supporting pro-Muslim Brotherhood brigades.
It currently appears that these groups will continue to receive outside support. However, should there be any shifts in the geopolitical environment — especially by nearby rebel allies such as Turkey, which is attempting to readjust its Syria policy while maintaining relations with Iran — it will cause foreign backers to reassess their positions just as al Assad allies such as Iran and Russia would re-examine their ties to the regime.
One potential scenario that could drive this type of reassessment is a rapprochement between Iran and the United States. The P-5+1 and Iran reached a breakthrough in nuclear talks in November 2013, when they agreed for the first time on a path toward a nuclear deal. Since then, both Iran and the United States have tried to slowly thaw their longstanding icy relations. Although there have been notable strides toward a nuclear agreement, there are still obstacles in the way of a full rapprochement — one of the most significant being Syria.
It appears unlikely that an understanding on Syria will be achieved in the near future between the United States and Iran. If it does, however, it will cause nearly every country in the region to reassess its role in the Levant. Depending on the terms of any future agreement, the shift in positions by rebel benefactors could threaten the rebels' ability to remain a capable and legitimate opposing force to the regime.
The outcome of each battle in Syria cannot be predicted, but the one thing that has remained a constant is the dynamic nature of the conflict and the almost constant ebb and flow of territorial gains and losses. Until one or more of the pillars of support for either the regime forces or rebel fighters is weakened or removed, the conflict will endure, with neither side capable of securing a decisive victory.