The Islamic State is a unique jihadist entity. Unlike all prior jihadist movements, IS has achieved the status of a state actor – it controls, governs and defends territory. Unlike the Taliban, which ruled Afghanistan for five years prior to the 9/11 attacks, IS established a transnational caliphate by disregarding the borders between Syria and Iraq. Taking advantage of the failing Iraqi and Syrian states, IS seized large tracts of territory on both sides of the border and set up a viable economy.

IS has not been able to expand the frontiers of its caliphate and has experienced some territorial losses since late 2015. However, IS remains entrenched in eastern Syria and western Iraq. More recently, it has also demonstrated the capability to stage transcontinental terrorist attacks, particularly in Europe.

The United States has pulled together a major international military effort to dismantle the two-year-old IS caliphate. This report seeks to understand the outcome of this American-led effort, which relies heavily on local and regional forces. We begin with a detailed assessment of IS’ current economic and military status.

We then examine a highly complex U.S. strategy to degrade the jihadist regime by carrying out offensives on its western and eastern flanks. The final section explains why, in our view, IS will not be destroyed (at least not any time soon), even though it may lose additional territories and be further weakened.

Our key findings include:

  • The tactical losses that IS incurs should not be interpreted as strategic gains for its opponents. IS will likely retain control over much of its core turf along the Euphrates River between Raqqa and Deir el-Zour.
  • IS will have to limit its spending, but its economy will likely survive because its opponents cannot shut down its revenue from taxing the population under its control.
  • In addition to the logistical problems facing IS’ challengers, they are composed of multiple actors with competing interests and thus suffer from deep incoherence.
  • Without accepting high levels of casualties, many of them civilian, IS’ opponents will not be able to dislodge it from its core turf.
  • In the event that IS is uprooted in the future, its opponents will find it very difficult to administer the liberated areas, thus creating the conditions for an IS comeback.
  • The one force that can prove to be an existential threat to IS is Turkey, but it has been reluctant to take the lead on the ground. Ankara fears that a weakened IS will enable Kurdish separatism at home and in Syria. Turkey is also generally hesitant to take a lead role in the broader Syrian conflict.
  • A future collapse of the caliphate will not necessarily mean an end to IS as an organization – the group has exhibited a strong ability to revive in the past. Even if IS is gutted at some point in the future, there is no shortage of other groups that can build on IS’ caliphal project.


At the political heart of classical Islam is the idea that the Muslim world ought to be governed by a single ruler – a caliph. Except for the time of Islam’s founding, there has never been a single, unifying caliphate encompassing the entire Muslim world. There have been multiple caliphates – often competing along with smaller polities such as emirates and sultanates – encompassing part of that world, some of substantial size. But never one single caliphate.

It has always been the goal of contemporary jihadists to re-establish the caliphate – and to see it challenge the non-Muslim world. Al-Qaida’s main goal in attacking the United States was to trigger uprisings in key U.S.-backed, Muslim-majority countries. Al-Qaida hoped to take advantage of popular dissatisfaction within these countries to create the foundation of a new caliphate. However, no mass Muslim uprising occurred, and al-Qaida did not seize a single state.

The Islamic State continued al-Qaida’s project not by overthrowing an existing state, but by attempting to create a new one. The key to this was seizing substantial territory in the weakened states of Iraq and Syria, which would serve as the geographic foundation of its envisioned caliphate. In adopting this strategy, jihadism moved from primarily carrying out terrorist attacks to forming a conventional fighting force designed to take and hold territory, with terrorism as a secondary tactic. This is a fundamental shift in jihadist strategy.


IS has created a conventional fighting force and it holds substantial territory. From our perspective, IS is one of the most impressive Arab fighting forces in generations. Its most impressive characteristic is its ability to absorb defeats, retreat, regroup and strike at weak points on its enemy’s front. The measure of an army is the ability to absorb and recover from setbacks. IS can do this well.

There is talk of defeating IS, which is measured in terms of retaking territory. The real goal should not be to retake territory, but the destruction of the enemy army, rendering it incapable of fighting and then taking territory. IS has undoubtedly experienced losses, but it has not lost the will or ability to fight. The fundamental question to be addressed in this study is the state of IS’ militarily, the likely course of the war and the future consequences of both its defeat and its continued survival.

The Economic and Military Standing of the Islamic State

The Islamic State has been losing territory in recent months. Syrian and Iraqi government forces have forced IS to retreat from major cities like Ramadi in Iraq and Palmyra in Syria. Spurred on by these victories, the coalition battling IS is pushing further, attacking the IS holdings in Fallujah and preparing for assaults on Mosul and the group’s de facto capital in Raqqa.

Reports have surfaced claiming that IS fighters are defecting in the wake of large pay cuts and that key leaders have been assassinated in U.S. airstrikes. This paints a bleak picture of the Islamic State’s near future. It seems to be on its last legs and will soon be crushed by its enemies.

Our assessment of the Islamic State’s situation on the ground is different. The notion that IS’ collapse is imminent misunderstands its position. IS maintains a firm grasp on power in its core territory and remains a credible terrorist threat both in the region and outside it. As we have written, rumors of the Islamic State’s demise are greatly exaggerated. IS may not be thriving, as it was at the height of its expansion in 2014, but it is certainly surviving.

Even so, the Islamic State is currently facing tremendous pressure, internally and externally. Advances from enemy forces have pushed IS back, toward its heartland, and economic pressures have begun to take their toll. In this section, we will examine how this has affected IS’ economic and military power. We will demonstrate that though IS may continue to lose money and territory, its position in its core strategic territory is relatively secure.

The Islamic State’s Economic Position

The Islamic State is extraordinarily well funded. Unlike its predecessors, however, the Islamic State does not rely on wealthy donors to bankroll its operations. Instead, IS has various methods of obtaining money independently. The most lucrative and reliable of these avenues is the taxation and extortion of the population living under IS control.

IS also makes a significant amount of money by selling oil, which is either smuggled to buyers in Turkey or Damascus or sold to citizens of IS-controlled territories. Other large sources of revenue include the sale of antiquities and the seizure of banks. Additionally, the Islamic State makes money from human trafficking, agriculture, real estate, the sale of looted property and natural resources.

The structure of the Islamic State’s caliphate requires revenue to be distributed among the various wilayat (provinces). These are semi-autonomous territories that vary in size and importance. They each have their own local authorities who report directly to the central leadership in Raqqa. The leadership then doles out money according to the requirements of each wilayah (province) to pay salaries and meet the needs of the fighters and citizens.

This is an easy fact to glaze over but it is in some ways the most important. IS manages a sophisticated economy whose priorities are established by a central governing structure. It is what makes IS different than any other jihadist group and is one of the deepest sources of its power.

The amount of money each wilayah receives has declined in recent months as the Islamic State’s economy has taken a hit. Coalition airstrikes have destroyed IS-controlled oil fields, the organization’s supplies of cash have been bombed, the loss of territory has reduced its ability to tax its population, and the tightening of Turkish borders has made it much more difficult to smuggle oil and antiquities out of Syria. These factors create an economic situation for the Islamic State that is uncomfortable – but not one that will shatter its economy.

Details on the size of IS’ economy are sketchy, but it is possible to make some educated guesses. The Islamic State arguably reached its financial peak in 2014. Its newly captured territories were rife with cash-filled banks, oil, countless historical sites and museum collections, and millions of citizens who could be taxed. Research done by the RAND Corporation suggests that when Mosul fell to IS in June 2014, the organization had approximately $875 million just in cash.

In 2014, the Islamic State is conservatively estimated to have made nearly $2 billion – $600 million from extortion and taxation, $400 million to $500 million from Iraqi banks, $500 million from oil and $20 million to $40 million from kidnappings. This does not take into account the millions made from the sale of antiquities, smuggled across the Jordanian and Turkish borders and sold to buyers across Europe.

Recent times have been harder for the Islamic State than the early heady days of 2014. Its opponents have tried to limit its cash flow in various ways. Oil production has been a major target. Though the United States has been independently attacking IS-controlled oil fields since late 2014, a coalition effort called Operation Tidal Wave II was established in October 2015 to strike at the Islamic State’s oil fields.

Prior to these airstrikes, IS was making an estimated $1 million to $2 million per day from oil sales. Coalition estimates suggest this has fallen by around 30 percent. Profitability was further reduced by Turkey’s decision to tighten its borders after heavy pressure from the United States, as well as low oil prices and the loss of many of the Islamic State’s oil workers.

Airstrikes have also targeted the organization’s general treasury, as well as IS-controlled banks and storage facilities where hard currency and gold were kept. In January, two airstrikes on banks in Mosul reportedly destroyed “tens of millions” in hard currency, according to U.S. Army Col. Steve Warren. Four more attacks were carried out in February, striking several banks, including the Central Bank of Iraq’s branch in Mosul, from which IS stole around $500 million in 2014.

The Islamic State has mocked these efforts, claiming that the banks and cash storage facilities were mostly empty. The United States and its allies have lauded them as a huge success. As usual, it seems that the truth is likely somewhere in between. These airstrikes have been painful, but they have not been enough to destroy the Islamic State’s economy.

Instead, reports suggest that IS has increased taxation and extortion to make up for lost revenue from oil and bank looting. The Islamic State taxes the population living under its control for a variety of things ranging from religious differences to bank withdrawals and electricity usage. As it loses revenue from other channels, IS has become more financially reliant on its citizens.

Unless the Islamic State’s opponents are willing to accept massive civilian casualties, this income source cannot be destroyed. Efforts have been made to reduce the available supply of cash, such as the Iraqi government’s decision in 2015 to stop paying the salaries of workers living in Mosul, but there is ultimately not much that can be done to stop IS from making money this way.

Taxation is the Islamic State’s most reliable and consistent source of income, but it has come under some pressure. IS has lost some territory, shrining potential sources of tax revenues, and the more it tries to squeeze out of its subjects, the less they have to give and the more hostile they become to IS in general. Recent reports suggest that the Islamic State’s leadership has responded to these financial pressures by implementing austerity measures, cutting the salary of fighters in Raqqa by 50 percent.

Its current economic situation is challenging, but IS will be able to manage and overcome these difficulties, at least in the short run. The wilayat structure and highly regimented bureaucratic system of taxation will make it difficult to cut the Islamic State off from its most important source of income: its people. Outside forces can continue to nip at the edges of IS territory, but this will not be enough to financially drain the organization.

The Status of the Islamic State’s Military

To evaluate the Islamic State’s current military position, we must first identify and examine its strategic imperatives. The Islamic State’s primary objective is to protect the region stretching from Raqqa to Deir el-Zour, which is the heartland of the Islamic State. This particular territory is critical to the Islamic State’s caliphate because it is arable land along the Euphrates River, and because it is easily defensible.

Raqqa is the Islamic State’s capital, where the majority of its fighters and leadership are stationed, and IS will defend it fiercely. To abandon it would spell the end of the Islamic State’s fledgling caliphate.

IS’ secondary objective is to keep Iraq divided while maintaining the ability to move troops, weapons and supplies back and forth between Iraq and Syria. Continuous instability creates fertile ground for IS and allows it freedom of movement. This is highly desirable for the Islamic State’s leadership, but it takes a back seat to the primary objective of defending the heartland.

To achieve this primary objective, the Islamic State must defend itself against invasions and attacks on the core territory from Raqqa to Deir el-Zour. There are four key approaches that enemies of the Islamic State can take.


The first and most attractive of these options is to drive down from the northern city of Hasakah to al-Busayrah, effectively cutting the heartland in half and leaving Raqqa and Deir el-Zour to wither. Hasakah is currently controlled by the Syrian Democratic Forces (SDF), a largely Kurdish alliance of approximately 30 local militias, estimated by the Syrian Observatory for Human Rights to have 50,000 fighters.

The SDF has retaken a large swath of territory in the northern part of Syria, liberating towns like Hasakah and Kobani. The group has recently declared this territory to be a semi-autonomous state and is calling it Rojava (Syrian or Western Kurdistan).

This has angered the Turkish government and put the United States, which has worked closely with the SDF throughout the conflict, in an uncomfortable position. Furthermore, the further the SDF progresses on this line of attack, the longer and more vulnerable its supply lines get. Its progress on this front has been stalled in recent months for that reason.

The second method of attacking the Islamic State’s heartland would be to seize control of Aleppo and use it as a staging ground to attack Raqqa. Currently, this would be very difficult to achieve: Aleppo is a hotbed of instability, with various rebel groups, Syrian President Bashar al-Assad’s forces, IS fighters, Jabhat al-Nusra and Kurds all vying for control of the city. Aleppo is critical ground for rebel groups like Ahrar al-Sham, the largest anti-Assad rebel group in the country, and Jaysh al-Islam, Saudi Arabia’s main proxy in the conflict.

The Islamic State is mainly interested in playing a spoiling role in Aleppo rather than dominating it. As long as no group is powerful enough to emerge as the clear leader, the heartland is protected. Assad’s forces hold a significant amount of territory in Aleppo and have promised to retake it with Russia’s support. The extent to which Assad’s forces can achieve this will be a function of how secure his regime’s position is in the rest of western Syria.

A third opportunity is to retake Palmyra and then either attack the heartland directly or cut it off from fighters and resources in Iraq. Assad’s forces retook Palmyra in March, which was lauded as a huge victory for the Syrian government. However, it appears that IS was not defeated so much as it retreated strategically. Further, the force that liberated Palmyra was not entirely composed of the Syrian military. It also included local militias and Hezbollah fighters sent by Iran.

This is unsustainable when considering what it would take to hold Palmyra in the long run, much less to push farther and attack Raqqa or effectively sever supply lines. It is not Palmyra that matters to the Islamic State, but rather the ability of opposition forces to use it to attack the heartland. Currently, Assad is neither willing nor able to use either Palmyra or Aleppo to strike Raqqa, which is why IS seemed to retreat without putting up much of a fight. The chances of this hodgepodge force attacking IS over long supply lines in the desert is low.

Lastly, the Islamic State’s enemies could attack Raqqa directly from the north of the city. But like Hasakah and al-Busayrah, this option would rely on the SDF. There are two main problems with reliance on Kurdish-led forces. First, the primarily Kurdish SDF is willing to fight IS in the hope that they will gain an independent state and the support of the United States. There is a limit to how much the SDF is willing to do and how far it is willing to push.

Second, even if the SDF were willing to attack the Islamic State’s heartland directly, there is the matter of numbers. As mentioned above, the SDF has around 50,000 fighters. Though it is impossible to know for sure, we estimate that the Islamic State currently has between 80,000 and 90,000 fighters. As more territory is lost, these fighters are drawing inward to defend the heartland.

For numbers to be evenly matched, the SDF would have to send every single fighter to Raqqa, which is impossible because SDF fighters are currently active on at least two fronts, including the current offensive in the countryside north of Raqqa. The Wall Street Journal estimates several thousand SDF fighters are battling IS in three villages 30 miles outside the city. These offensives are more of a containment strategy than a direct assault at this point.

Even with American support, a direct assault on Raqqa would result in extremely high casualties. The SDF is not suicidal, and its priority is protecting its heartland in Rojava. Therefore, this method of attack seems very unlikely given the current situation.

The Islamic State’s secondary objective begins with keeping Iraq divided, which it aims to do by provoking the ever-present sectarian tensions that threaten to destroy Iraq’s limited progress towards stability. Continuing to exploit the intense sectarian rivalry between Sunnis and Shiites in Iraq not only supports the Islamic State’s strategic goals, but also serves as a recruiting mechanism.

This explains the importance of Fallujah, which is the Islamic State’s primary staging ground for terrorist attacks in Baghdad. Retaking Fallujah is imperative to the future of the Iraqi regime, though the Islamic State is reportedly putting up firm resistance against great numbers.

The Islamic State will want to prevent the Iraqi security forces from retaking too much territory and reintegrating the Sunnis into the Iraqi political system. The best-case scenario in the minds of IS leaders would be to foment civil war, which would allow the organization to grow unchecked in Iraq.

This secondary objective also includes keeping supply lines open and maintaining the ability to move men and weapons easily through the extremely porous border between Iraq and Syria. It also requires keeping control of both Mosul and a good part of Anbar province, which serves as a large support zone for the Islamic State.

Recent reports suggest that tribal fighters around Mosul are being recruited to fight IS by the United States and its allies. If this is any indication that anti-IS sentiments are growing among the tribes in Anbar, the Islamic State may lose its ability to travel freely through the province, severely limiting its mobility in Iraq.

In Mosul, Kurdish peshmerga forces are reportedly attacking areas outside the city with 5,000 fighters and U.S. air support. However, this is likely more of an effort to besiege the city than a direct assault. The Pentagon estimates that IS has 10,000 fighters stationed in Mosul. Because those fighters are deeply entrenched in the city and have had time to lay booby traps and plant explosives, as they have done in Raqqa, 5,000 peshmerga fighters are simply not enough to take back Mosul.

The only group in Iraq that is currently capable of taking back Mosul is the Iraqi security forces. Research conducted by the Al-Bayan Center estimates that Iraqi forces currently stand at about 80,000 troops. If support personnel and tribal militiamen are included, the number grows to 190,000. In theory, this number is more than enough to retake Mosul from the Islamic State.

The reality, however, is that the Iraqi forces are plagued by sectarian rivalries, low morale and a history of desertion. Despite having a 10-to-1 advantage and $25 billion worth of American equipment and training, Iraqi forces fled Ramadi in 2015 without putting up much of a fight.

Additionally, Mosul is far away from Baghdad. The Iraqi government’s first priority must be to protect the area it already controls, so it is presumably unwilling to send the necessary number of troops all the way up the Tigris River to confront IS in Mosul. An advance on Mosul will likely happen only after the Iraqi government has strengthened its grip on the south.

Examining the current standing of the Islamic State’s primary and secondary objectives demonstrates that, despite recent territory losses, IS is bent but not broken. It maintains complete control of its heartland – no enemy forces are currently able to directly attack it successfully without suffering high levels of casualties, to say nothing of the potential toll on civilians.

Furthermore, though it may be losing supporters in Anbar province, IS is unlikely to lose Mosul in the coming months, simply because there is no willing force that is capable of retaking it – and no capable force that is willing.

This keeps its supply lines open and lets fighters and resources move between Iraq and its heartland in Syria. The Islamic State has lost territory and likely will continue to do so, but as long as it maintains control of the heartland from Raqqa to Deir el-Zour, it retains its defensible position.

The Efforts to Counter IS

IS is not completely on the defensive. It has continued to take advantage of its opponents’ weaknesses even as it has come under duress. Despite the pressure from the SDF, peshmerga and Iraqi forces, in recent months IS took areas from Syrian rebels in Aleppo province, staged an attack on the cities of Haditha and Hit in Iraq and carried out suicide bombings in Ramadi and Baghdad.

Iraq and Syria have been destroyed and are not coming back as the nation-states we have come to know. Their demise was not triggered merely by the rise of IS. Instead, Syria and Iraq have imploded because of three key dynamics: autocratic meltdown, geopolitical sectarianism and transnational jihadism.

Even if the Islamic State were somehow defeated and Turkey and Iran – the two main regional stakeholders – were to settle into a peaceful coexistence, the area between the Mediterranean Sea and the Zagros Mountains would still be fragmented into multiple Sunni, Kurdish and Shiite entities. The Islamic State’s opponents lack coherence, and the complexity of the Iraqi-Syrian battlespace makes it very difficult to mount a successful military campaign against IS.

That said, since military operations in Syria and Iraq are distinct, it is still useful to examine the anti-IS efforts in each country separately. In Syria, non-state actors lead the fight. In Iraq, the Iraqi government and the Kurdistan Regional Government (KRG) lead the struggle. This is the key difference between the two countries. There are far fewer stakeholders in Iraq than there are in Syria. Not only are there far more armed factions in Syria, the majority of rebels are Sunni, while the bulk of those fighting IS in Iraq are either Shiites or Kurds.

The Situation in Iraq


In Iraq, there is an internationally accepted political system, although it is extremely weak. It is made up of three main communal groups – the Shiites, Sunnis and Kurds – and was established by the United States after the collapse of Saddam Hussein’s Baath Party. Defeating IS entails getting the country’s Sunnis to rejoin the post-Baathist republic. This will be extremely difficult because of how the Shiite-dominated government has dealt with the Sunni minority community.

In 2007, Baghdad double-crossed the Sunnis after they agreed to end their insurgency and join the system. In addition, the Iraqi central government’s efforts to play various Sunni factions off one another acutely sharpened divisions within the minority sect.

Finally, after U.S. troops departed in 2011, the Sunnis experienced greater persecution at the hands of the Shiites. These three factors became the key enablers for IS to stage its comeback in Iraq and will make it very difficult to tear enough Sunnis away from the jihadist regime.


This Shiite-Sunni fault line is a critical element behind the fracturing of the Iraqi nation-state. However, it is not the only one. The Kurds are also exploiting this highly polarized sectarian climate to gain as much autonomy as they can.

The central government and the KRG have not been able to agree on the scope of Kurdish autonomy, and the Sunnis dispute territory with the Kurds, given the proximity of the Kurdistan region with Sunni-majority provinces. Kurdish efforts to expand their control into Nineveh, Kirkuk and Diyala during the years that the U.S. military was battling Sunni insurgents further aggravated this ethnic strife.

Thus, fracture of the Iraqi state is not only due to the Shiite-Sunni split, but also the Sunni-Kurdish and Shiite-Kurdish conflicts. In addition, each of these three groups is deeply divided internally. The Islamic State has greatly benefited from these inter- and intra-communal differences. A key weakness in the efforts to fight IS is that this struggle is being led by the Shiites from the south and the Kurds from the north, which enhances Sunni fears.

The Situation in Syria


In Iraq, the conflicted and ineffective government undermines the fight against IS. In Syria, the Assad regime has lost legitimacy, so the fight against IS takes place alongside the struggle to establish a new regime. These two simultaneous conflicts have fractured the country into at least five different parts, as shown in the map above.

In addition to this fracturing, the United States and its regional allies have different priorities in Syria. For Washington, the first priority is to defeat IS. Assad can be dealt with later. For the regional allies, toppling Assad is the priority, and once that is achieved a strong coalition against IS can be cobbled together.

However, it is very likely that the vacuum that would emerge from the weakening (or worse, collapse) of the Assad regime would only benefit IS. Furthermore, Jabhat al-Nusra, al-Qaida’s Syrian outfit, plans to establish its own emirate, and a majority of the rebel forces are Salafist-jihadists. This is why Washington has prioritized the fight against IS and why it is forced to rely on Syrian Kurds to be the ground forces against IS over the objections of Turkey.

The Syrian Kurds dominate the SDF, which also includes other religious and ethnic minorities. The SDF has enjoyed some relative success on the battlefield. But given that the SDF has a very small Sunni Arab component, it will be perceived as a hostile force by those in Raqqa, which works in IS’ favor.

One of the reasons the SDF has been so cooperative with the U.S. is that the Syrian Kurds need the Americans’ protection from the Turks. The Kurds are in a precarious position, holding land that is mostly on a flat plain and not easily defensible. Securing territory for a state of its own is the Syrian Kurds’ foremost interest, and cooperating with the U.S. in fighting the Islamic State remains the best way for them to secure it. Even so, there will be limits to how far the SDF will be willing to go in attacking IS and how its forces will be accepted by Sunni Arab locals currently under IS rule.

Turkey sees the Kurdish groups in SDF as a threat equivalent to, if not greater than, the Islamic State. In recent weeks, however, the Turkish government has signaled that it is prepared to align with the United States to take on IS.

Turkish Foreign Minister Mevlüt Çavuşoğlu said on May 30 that his country is ready for a joint offensive with the United States against IS, on the condition that the Syrian Kurds are not part of the operation. On June 7, Turkey said it had been given assurances by the U.S. that Syrian Kurds will not engage in fighting west of the Euphrates – suggesting that an understanding has been reached between Washington and Ankara.

The Assad regime – backed by Iran, its Shiite allies on the ground and the Russians in the air – could be a significant force in the fight against IS. But the U.S. and others combating IS cannot publicly align with the government in Damascus since it is seen as responsible for the deaths of close to 300,000 of its citizens. Also, the Assad regime has a complex set of priorities.

Assad will do whatever he needs to do to secure the areas currently under his regime’s control. His forces will fight rebels or IS or whoever else gets in their way. Since the rebels have posed the greatest challenge, the regime has largely concentrated on them, but it has also confronted IS – retaking the Kweiris air base in Aleppo in November, for example.

Further, the presence of IS makes Assad look good in comparison. As long as IS remains a major problem, it is unlikely that there will be a meaningful international effort to force Assad to step down. Thus, the regime has an interest in the survival of an Islamic State, so long as it does not threaten the regime or collapse in on itself.

Meanwhile, IS continues to demonstrate that it can fight on multiple fronts and strike in unexpected locations. It used suicide bombings in the Syrian regime’s stronghold of Latakia and the Iraqi cities of Ramadi and Baghdad, and has also used conventional military methods to push closer to the Syrian city of Azaz and assault the Iraqi city of Hit.

Even if anti-IS forces are able to take back territory, it will be an even bigger challenge to make sure it does not fall back into the Islamic State’s hands. The underlying geopolitical sectarian conditions that enabled IS to rise remain unaddressed. On top of that, the ethnic and sectarian differences among the forces countering IS only add to the chaos.


What to Expect from the Anti-IS Campaign

The fact that the Kurds are the main players in the campaign to defeat IS works well for IS because it benefits from the ethnic tensions. IS can take advantage of Turkish opposition to the Syrian Kurds. On June 2, President Recep Tayyip Erdoğan told reporters that the United States had assured his country that the fight against IS would be led by Sunni Arab fighters and that the Syrian Kurds would constitute a small force focused on logistics.

However, Erdoğan added that Turkish intelligence was monitoring the situation to ensure that the composition of the anti-IS force was indeed majority Sunni Arab, which suggests that Turkey was still concerned despite American assurances.

Even if the anti-IS coalition is able to press ahead with its offensive, its ability to succeed is questionable. IS is in control of significant parts of Aleppo province, between the Syrian Kurdish cantons of Kobani and Afrin. If it can continue to dominate parts of Aleppo province, it will ensure that no force can threaten Raqqa from that approach.

In fact, in recent days IS has mounted an offensive westward toward the town of Azaz, which is held by Sunni Arab rebels. Its goal is to open a second front against the Kurdish enclave of Afrin to take the Syrian Kurds’ focus away from Raqqa.

If the major Sunni Arab rebel groups attack IS instead of focusing on the Assad regime, it could be a game changer. Taking over the Sunni lands in eastern Syria from IS would give the rebels strategic depth against the government in Damascus and get them American backing.

But the likelihood of the rebels making such a strategic shift is extremely slim, as they do not want to give the Syrian state the time and space to further revive. The rebels are also internally divided and thus weak in the face of a unified and much stronger group.

The Assad regime might also take the fight to IS, considering the recent statements from Damascus. The Syrian regime would like to take advantage of the assault on Raqqa to try and regain control of IS territory and prevent the rebels from doing the same.

The extent that the regime jumps into the fight against IS will depend on its bandwidth. Given its need to fight on multiple fronts and the possibility that the assault on IS may not succeed, the likelihood of the Syrian regime mounting a decisive attack on IS is quite low.

The one force that has the capability to cripple IS is Turkey. The United States has been pressing Turkey to take the lead in a ground assault, with the U.S. providing air support. However, any Turkish incursion will not be a quick operation.

On the contrary, it will involve a long-term military commitment from the Turks that will include fighting IS, the Syrian Kurds, the Russian-backed Assad regime and Iran. Having to simultaneously counter these groups is the reason Turkey is still reluctant to play a lead role.

Thus, the ground forces required to reduce IS back to the status of a non-state do not presently exist.

Meanwhile, in Iraq, despite all the media noise surrounding the Baghdad government’s attempt to retake Fallujah from IS, the operation has run into problems. Reports suggest that the Iraqi army, backed by the Popular Mobilization Forces militia, has encountered stiff resistance from IS, which appears well entrenched in the town. The government is trying to make the argument that the operation is stalled because an offensive could endanger the lives of tens of thousands of civilians.

There is also a disconnect between Washington and Baghdad on the geographic priorities in the fight against IS in Iraq. From the point of view of the Shiite-dominated government of Prime Minister Haider al-Abadi, the priority should be to dislodge IS from Anbar province, particularly from its stronghold of Fallujah. These areas are only tens of miles away from the capital, which remains highly susceptible to suicide bombings.

The American priority, however, is Mosul – the country’s second largest city. U.S. army spokesman Col. Steve Warren has said retaking Mosul does not require recapturing Fallujah. There have been reports of Shiite militia leaders criticizing the Abadi administration for having redirected resources to Mosul under U.S. pressure.

For the KRG in northern Iraq, Mosul has to be the priority, since the city is close to the Iraqi Kurdish territories. On May 29, media reports indicated that KRG peshmerga forces had taken five villages as part of a major operation to push IS out of Mosul. KRG’s security forces are also facing stiff resistance from IS fighters.

As is the case in Syria, ethnic divisions are undermining the anti-IS offensive in Iraq. Iraq’s Sunni Arabs do not want to see their areas go from IS to Kurdish control. Iraqi Kurds have been able to expand their control into Sunni areas as part of the efforts against IS over the past two years. But perhaps the biggest obstacle to any anti-IS campaign is the fact that the Iraqi government and its allied militias are dominated by Shiites. IS can exploit these ethnic and sectarian rivalries to its advantage.

In both Iraq and Syria, IS has also demonstrated considerable prowess on the battlefield. Though it has lost ground since late 2015, IS remains fairly secure given that reaching its core territories involves crossing desert terrain, where any attacking force will run into supply line issues.

Furthermore, IS has proved to be a capable fighting force combing conventional military, guerrilla and terrorist tactics. This is especially the case when, faced with an overwhelming force, it has conducted an orderly retreat and quickly regrouped to mount an assault in a different area to force its enemy’s hand.

While IS can conduct strategic pullbacks, there are serious questions regarding its opponents’ ability to hold areas taken from IS. This is especially the case for forces composed of fighters who are not Sunni Arabs, including the Shiite Arabs in Iraq. Forcing IS out of an area is much easier than maintaining control over it. Bad governance adds to the problems, which create the conditions that enable IS to stage a comeback.

This means the anti-IS forces backed by U.S. air power must severely degrade IS as an organization. The battlefield advantages discussed earlier notwithstanding, IS will face a lot of strain on its system as it fights on multiple fronts. The ground assaults also force IS to deploy in large formations to defend its territory. But doing so renders IS forces highly vulnerable to American air power.

Therefore, it is likely that at some point in the future, as the coalition gains strength, IS as an organization will sustain heavy blows and lose the ability to hold on to territory. Losing the caliphate would not lead to the end of IS’ ideology.

Rather, other organizations will emerge from the fighting to assume control of the jihadist movement in Syria. The destruction of the IS caliphate would thus render Syria a much more chaotic battlefield for many years, after which either IS could revive or a new successor organization could emerge.

A key historical example of a group that formed out of a splintered jihadist movement is the Taliban in Afghanistan during the mid-1990s. The Taliban emerged as a new organization from the civil war between the Islamist insurgent groups that had earlier driven out the Soviets and toppled the Marxist regime. IS is a successor to al-Qaida. The withering away of a particular organization is not the same as defeating the jihadist ideological movement.

There are plenty of other groups, especially in Syria, that are ideologically similar to IS. Already, the Syrian branch of al-Qaida, Jabhat al-Nusra, is in the process of establishing its own emirate. The largest rebel group in Syria, Ahrar al-Sham, is also a Salafist-jihadist force, and there are many other such factions.

While currently focused on fighting the Assad regime, these groups will try to benefit from a weakened IS. They may not wish to hold on to the caliphate, but the caliphal project will remain for other groups to build on.