A great deal of military activity is taking place in Syria, which warrants a closer examination of the country’s battlespace. The regime of President Bashar al-Assad continues to be resilient. While under pressure, the Islamic State retains control of its critical territories. Meanwhile, the rebels are losing ground.

  • The war can be divided into four theaters: the Islamic State, the Battle of Aleppo, the rebel stronghold of Idlib and the southern front.
  • Much of the fighting is in the north because of, among other reasons, the border with Turkey, which provides sanctuary for the various opposition forces.
  • The south sees less activity because of its sparse population, the regime’s strong hold on the capital and surrounding areas, and the borders with Lebanon, Jordan and Israel – countries that do not want to see the regime toppled.
  • While the regime, the Islamic State and the Kurds are each unified entities, the rebels remain utterly divided.


Civil war in Syria has been raging for five years. In our 2016 annual forecast, the Islamic State was the center of gravity for the conflict in Syria, and our projections for the year revolved around them. So far those projections are on track. However, there has been a flurry of activity in the last two months that has necessitated re-examining the Syrian battlespace.

The Players

Before we can map out the conflict, we must lay out the players. The proliferation of participants is one of the reasons this war is so opaque. There are scores of militias operating in Syria. Included in these are the small and relatively ineffectual U.S.-trained and supplied fighters.

The Syrian Kurds – under the leadership of the Democratic Party of Syria (PYD) and its armed wing, the People’s Protection Units (YPG) – are the most unified. But they have committed to joining the Syrian Democratic Forces (SDF), a U.S.-backed hodgepodge of groups containing Kurds, Christian Arabs and a small number of Sunni Arabs.

The SDF has anywhere between 30,000 and 50,000 fighters. This coalition operates mostly in western Syria, dominating Hasakah province and putting pressure on the Islamic State (IS) from the north. It recently forced IS to withdraw from Manbij.

The Syrian rebels have a sizable number of fighters. Cobbling together various estimates from open source documents, a conservative figure would be about 100,000 rebel fighters. Some of these factions have access to tanks or to U.S.-supplied weapons, but they are still at a disadvantage to the Syrian regulars, who are backed by both Syrian and Russian air support.

The main problem, however, is that the opposition remains hopelessly divided. Even in the areas where the most rebel cooperation is happening – in the opposition’s territorial core of Idlib and Aleppo provinces – there are still tribal, political, ideological and religious differences limiting these groups’ effectiveness.

On the other side, the Syrian military has seen better days but still counts 150,000 soldiers in its ranks. Besides this, there are various pro-regime militias, the largest of which is the National Defense Forces, which is estimated to have between 35,000 and 90,000 fighters. Various Iran-mobilized militias and Hezbollah fighters also number in the low thousands and help the Syrian forces maintain relative supremacy on the battlefield. The combination of greater numbers and better equipment also allows Assad loyalists to fight on multiple fronts rather than concentrate resources on a single battlefield.

Lurking behind all of this is the Islamic State. Our assessment of the Islamic State remains that it is bent but not broken, and that both its capabilities and the number of its fighters have been woefully underestimated by the U.S. government and by the mainstream media. A U.S. congressional panel said as much on Aug. 11 when it claimed that U.S. Central Command had manipulated its intelligence reports to present a “rosy” assessment of the fight against IS.

We estimated in December 2015 that IS forces numbered close to 100,000 fighters. Various losses and attrition must be taken into account, but still, IS has shown consistently that it is willing to retreat rather than sustain too many casualties. We think it is still reasonable to posit that IS’ fighting force is somewhere between 50,000 and 80,000 strong.

The Main Centers of Gravity


The Islamic State Front in Syria

In our net assessment of the Islamic State, we identified IS’ core territory as the narrow band of land between Raqqa and Deir el-Zour in eastern Syria. This remains the case. Much has been made of the fact that Manbij was recently liberated from IS. This was a major PR victory for the SDF but a minor strategic victory.


IS, as it has so many times before when finding itself in a weak position, withdrew from Manbij. Reuters reported on Aug. 13 that as many as 500 trucks were seen leaving the city with IS fighters and supplies before the SDF forces arrived. Already, Turkey is demanding that the Kurdish fighters in the SDF withdraw east of the Euphrates. This is a combined force of perhaps 5,000 to 10,000 mixed fighters; it is not a force that is about to march on Raqqa.

Various reports have said that the seizure of Manbij means IS is cut off from the Turkish border, which it has used to smuggle fighters and supplies. However, as can be seen above, IS still holds a corridor of land on the border that is connected to Raqqa. And IS still holds the now-strategic small city of al-Bab. IS has also been aggressive in Aleppo province, engaging in various attacks meant to prevent any power from establishing dominance in the area.


Meanwhile, the SDF has stopped its approach toward Deir el-Zour from Hasakah. And despite its rhetoric, it has not shown any practical signs of preparation for a frontal assault on Raqqa, either by going down the Euphrates town by town or attempting an assault from Ayn Issa directly north.

The SDF has slowed for three reasons. First, it has a limited number of fighters. Second, the further it goes, the longer its supply lines and the easier it is for IS to attack them. Third, the SDF is dominated by Kurds. Further advances for the SDF mean Kurdish fighters seizing Arab-majority areas. Many Arabs don’t trust the Kurds any more than they trust IS, and the Kurds don’t necessarily want to take over areas so far from their base of support.

The main challenge to the Islamic State right now actually appears to be from the less discussed but no less strategic city of Deir el-Zour. Raqqa is the IS capital in Syria, while Mosul is its stronghold in Iraq. If IS loses Deir el-Zour, it is effectively cut in half and loses the ability to move supplies and fighters across the Syrian and Iraqi deserts.

Russian airstrikes against Deir el-Zour have increased recently, and there have been reports of Syrian loyalists amassing in Palmyra and Homs. From Palmyra and Homs, they can both beat back IS around those cities and also eventually march on Deir el-Zour to free up two brigades that have been surrounded by IS for more than two years. IS is taking this threat seriously enough that on Aug. 2 it transferred a “large number” of fighters from Raqqa to Deir el-Zour, according to the Institute for the Study of War.


Despite the fact that it has the upper hand, IS has not been able to break the spirit or defenses of these two Syrian brigades, which have had constant Russian and Syrian air support. Every time IS tries to advance, it is pushed back.

Deir el-Zour is not under imminent threat from any one source, but the Syrian regime looks resilient. The SDF is crowding in from the north. Russian and Syrian airstrikes are accelerating. And small U.S.-backed Syrian rebel groups are attempting (albeit unsuccessfully so far) to attack near Deir el-Zour. It is clear why IS is particularly worried about this front.

The other battles in Syria are important, and we will be addressing some of them in depth, particularly the Battle for Aleppo. But the Islamic State remains the main focal point of this conflict. It affects everyone else involved and has prevented any one power from dominating. IS will continue to face pressure both on Raqqa and Deir el-Zour, but we also expect that as its attackers begin to encroach upon its most important strategic territory, IS will fight tenaciously. It has been preparing for the defense of Raqqa and Deir el-Zour for years now and has nowhere to retreat.


The Battle of Aleppo

Aleppo is the center of gravity in the conflict between the Assad loyalists and Syrian rebels. Aleppo is Syria’s largest city and pre-war commercial capital. It is located in the wider province of the same name, which has a long border with Turkey – the rebels’ main staging ground. Many different battles are raging in the province of Aleppo. They involve regime forces, different rebel factions, al-Qaida’s Syrian affiliate, the Islamic State and separatist Kurds.


Syrian regime forces now surround rebel positions in Aleppo. But despite laying siege to the rebel territories, the regime isn’t in a position to celebrate just yet.

On July 31, a rebel coalition force launched a counteroffensive from the southwest. The jihadist-led force consists of fighters from the rural areas southwest of Aleppo as well as from the Islamist rebel stronghold in neighboring Idlib province. They hail from the secular nationalist Free Syrian Army, Ahrar al-Sham (the biggest Syrian rebel group) and the Jabhat Fatah al-Sham (known as Jabhat al-Nusra before it severed its ties with al-Qaida). The latter two are operating under the banner of the Islamist alliance known as Jaish al-Fateh, which also includes other smaller Islamist factions.

While the situation on the ground is fluid, for the time being the rebels have been able to connect two separate enclaves under their control by piercing a hole through the thin artery of government-held territory in the Ramouseh area. But the rebels’ advance is ephemeral. Their positions are already under counterattack, and it is still difficult for supplies to reach them.

The supplies they are able to get come from Idlib, which can still be resupplied from Turkey. But that means a much longer supply line that can be interdicted well before the supplies arrive anywhere near the forces amassed in Aleppo’s southwest. There is a small rebel enclave in the northwestern periphery of Aleppo province, along the border with Turkey. However, it is under dual pressure from IS, which controls territory to the east, and the Kurdish enclave of Afrin to the west.

The rebels, motivated in part by desperation, have demonstrated unusual unity in their efforts to pierce into the Ramouseh area, but it will be very difficult for them to team up with their comrades in eastern Aleppo to push outward against regime forces, especially since the eastern rebel-controlled districts have been battered by the regime’s attacks. Also, Kurds control the large area known as Sheikh Maqsoud, not far from the Castello Road. The PYD and YPG forces have tended to either remain neutral or they have clashed with rebel forces.

There is also the matter of Jabhat Fatah al-Sham, which is indeed a force multiplier for the rebels, but it is also a source of contention. More importantly, the United States remains completely opposed to the group, even after its separation from al-Qaida. Meanwhile, Russia continues to bomb the group and its rebel allies. Turkey, the rebels’ main ally, has also shifted gears in the wake of the attempted coup and appears to be warming up to Russia, which also spells bad news for the rebels.

Therefore, the rebels will not be able to revive themselves in the Aleppo theater. However, this does not mean that the regime will be able to flush them out of the city anytime soon. What we have for the time being is an uneasy stalemate.

The Rebel Stronghold

The battle for Aleppo is far from over, as the recent weeks’ advances and countermoves have made clear. Even so, the Assad regime has the upper hand in Aleppo, and if Aleppo falls, the rebels have only one place to retreat to – Idlib province. The Syrian regime has slowly hemmed in the rebels in Idlib, advancing from Latakia at the end of 2015 with Russian air support. Now the regime is pushing on rebel positions from Aleppo.

Idlib is also subject to air attacks from both Syrian and Russian forces, and even the Islamic State has been able to conduct terrorist attacks in the city. Even so, Idlib is not a major battle zone yet. Idlib is important for political reasons – it is the place where the bulk of the rebel forces intermingle and either cooperate with each other or compete for influence.

Reports surfaced earlier this month that Jabhat Fatah al-Sham pulled its fighters from the south in order to embed more deeply into opposition groups in Idlib and also to be at the front of the charge for Aleppo. This has boosted the group’s credibility among those who are suspicious of it because of its al-Qaida connections.

Idlib, then, is important for political reasons. It is also important because it is the last real rebel stronghold and is a lifeline to supplies and material from Turkey. If the Battle for Aleppo should go south for the rebels, the Battle for Idlib will come next, and there is not much the rebels will be able to do once it gets to that point.

The Southern Front


The forgotten front of the Syrian war is in the southwest. Damascus is not the core of the Alawite Assad regime – the Alawites are concentrated mostly in Latakia on the coast. Even so, Assad has made maintaining control over Damascus a priority. The fact that he has been able to do so is a testament to how many Sunni Arabs benefited from Assad’s rule and identify with the regime over the rebels.

Initially, it seemed the rebels might succeed in threatening Damascus, but after the July 2012 suicide bombing that targeted the National Security Council headquarters and killed several top officials, Damascus has not been seriously threatened by rebel forces. In fact, the initial uprising against the regime in different parts of the capital was put down in a week. Since then, a loose rebel alliance has been based in the eastern Ghouta region (the largest rebel enclave near the capital) but has not been able to mount any serious challenge to the regime in the past four years.

The most potent rebel forces in the south are based in Deraa and Quneitra provinces along the Jordanian and Israeli borders, respectively. Here again we see several different rebel groups that both compete and cooperate. Since 2014, the main force has been the Southern Front, which consists of 54 different secularist and moderate Islamist factions. The Jaish al-Fateh alliance operates a southern command in the area as well.

IS maintains a small presence in the south through various proxy groups, but these fighters only number in the low thousands. Still, this again goes to show how IS affects the entire situation, as the rebels have had to expend a considerable amount of their limited resources fighting IS at the same time that they are attempting to push their campaign against Assad.

The land from the eastern half of Suwayda province northeast to al-Bukamal and north to Palmyra is inhospitable desert and sparsely inhabited. Then, in sharp contrast with Turkey, Jordan and Israel do not provide sanctuary to the rebels. And a good chunk of Lebanon, the third country bordering southern Syria, either actively supports the Syrian regime or does not want to see its demise.


This report is the result of abandoning our assumptions and looking at the conflict in Syria with fresh eyes. We found that there are four key centers of gravity shaping this conflict. The Islamic State remains the ultimate variable, affecting everything around it. IS is under pressure but is still formidable, and neither the Kurds nor the regime seem poised to deal it a decisive blow in the near future.

In Aleppo, the Syrian regime continues to make slow and steady progress against the fragmented opposition. Loyalist success in Aleppo will eventually put pressure on the last remaining rebel stronghold, Idlib, where the various opposition groups continue to fight as much among themselves as with Assad. The southern front is still active, but stable relative to the other fronts, with the regime in a strong position. The war is progressing, but it is far from over.