The Battle for Mosul and the Future of Islamic State

Islamic State Militants in Anbar Province

On March 24, the Baghdad government announced that it was commencing military operations to retake the city of Mosul from Islamic State. The predominantly Sunni Muslim city, the second largest overall in Iraq and the largest urban area controlled by the Islamic State, has a prewar population of approximately two million people.

The announcement did not come as a surprise and was consistent with Iraqi military operations already underway in Makhmur, in Ninevah province, to cut off Islamic State positions in a pocket surrounding the town of Hawija. At this point, it is unclear whether Iraqi forces are planning to surround Hawija and then bypass it, or whether they plan to take control of the town and the surrounding region prior to commencing operations directly against Mosul.

The Iraqi advance coincided with new offensives by the Syrian Army east of Homs to retake the cities of Al-Quaryatayn and Palmyra. The latter includes the archeological site containing the ruins of the ancient city of Palmyra. By March 26, Syrian military forces were advancing into the city and had taken control of the western and northern parts of the city and were in full control of the al-Amiriya district on the northern edge of Palmyra. The city also sits astride the road from Damascus to the IS held eastern city of Deir ez-Zur. (Update: on March 27th, the Assad government announced that Islamic State militants had withdrawn from the city and that Syrian troops were now in control of Palmyra.)

In the meantime, troops from the U.S. backed Syrian Democratic Forces (SDF) were within 20 miles of the Islamic State's capital of Raqqa. The SDF is comprised of troops from the Kurdish YPG and YPJ military forces along with Sunni Arab and Christian militias. In a broad pincer movement one column of SDF forces advanced from the recently captured village of Ash Shaddadi directly east while a second column advanced from the town of Suluk directly north of Raqqa. The advance cut off a roughly 4,000 square mile area to the northeast from the Islamic State capital.

To the south, the New Syrian Army, another group backed by the U.S. and the Saudi led Gulf Cooperation Council, had begun a new offensive to seize control of Deir ez-Zur in the northwest. Also significant, another group of Syrian rebels have advanced to within six miles of the town of Dabiq, while Syrian government forces are advancing on Dabiq from Al-Bab in the southeast and SDF forces are advancing from Manbij in the east.

The town is situated 30 miles to the northeast of Aleppo and holds particular ideological significance to the Islamic State. Dabiq was mentioned in a hadith, a "verified comment" by the Prophet Muhammad, as the location where an apocalyptic battle would occur between Muslims and infidels involving "all the armies of the world" that would usher in "the end of days." In the confrontation, the prophet Isa (Jesus) would appear to lead the Islamic forces over their infidel opponents ensuring the final victory for the "true believers." This prophecy is at the core of the Islamic State's apocalyptic vision of how Islam will triumph and come to rule in a worldwide caliphate.

The Islamic State has named its glossy propaganda magazine Dabiq, and each issue prominently features the quote from Abu Musab Zarqawi, "The spark has been lit here in Iraq and its heat will continue to intensify -- by Allah's permission -- until it burns the crusader armies in Dabiq."

The fall of Mosul would be a critical loss for the Islamic State. The outcome of the Iraqi campaign to take it will be long and difficult, however, and success is in no way assured. There are three crucial elements that will dictate the likelihood of success of the operation to take Mosul: the military campaign itself, the political issues surrounding the campaign and how IS will respond both within Iraq and abroad.

The military aspect of the campaign is relatively straightforward. Kurdish Peshmerga forces have surrounded Mosul from the north, east and west. With the capture of Tal Afar, all of the major highways leading to the north, east and west, highways 47, 1, 2 and 3 have all been cut off. Highway 1 to the south, from Mosul as far as Baiji, is still more or less in the hands of IS, as are portions of Highway 80 immediately around Mosul as far as the juncture with Highway 3. Current Iraqi military operations in Makhmur, and eventually al Qayyarah to the west, combined with an Iraqi drive up Highway 1 from Baiji, would finish the encirclement of Mosul. Although some secondary roads would remain open, they would not allow much access to additional IS supplies or military forces in Syria.

Based on the prior experience with the recapture of Tikrit and Ramadi, the liberation of Mosul is likely to see a prolonged urban campaign characterized by protracted street-to-street fighting with liberal use of IEDs and booby traps as well as the use of tunnels to strike unexpectedly at the rear of advancing Iraqi troops. While close air support and the use of precision munitions to target IS strongpoints will give the advancing Iraqi army a significant advantage, the campaign will likely be long and difficult and will take, at the very least, the better part of 2016 and will likely extend into 2017. Moreover, there is a significant civilian population still in Mosul. As of February 4, 2016, it was estimated that there were still 700,000 civilians in the city. By comparison there were hardly any civilians left in Tikrit and only about 4,000 in Ramadi when those campaigns began.

According to Iraqi government sources it's estimated that there are approximately 10,000 IS militants still in Mosul. At this point it is still unclear whether Islamic State will withdraw any of those fighters in anticipation of the attack on Mosul. Originally Baghdad estimated that it would need approximately 24,000 soldiers to recapture the city. Pentagon sources placed the number at close to 40,000. Both numbers may turn out to be to low, however. By comparison, Tikrit was held by around 1,000 IS militants and Ramadi by approximately 2,000 militants.

The Tikrit campaign took two months and the Ramadi campaign close to four months before each city was effectively secured. In the Tikrit campaign, Iraqi forces had a better that ten to one advantage over IS militants, although the Iraqi forces were made up primarily of poorly trained Shia militias. In the case of Ramadi, the Iraqi force was made up primarily of regular Iraqi Army units and Iraqi Special Forces, but here again they enjoyed a better than five to one numerical advantage.

The political issues surrounding the Mosul campaign will weigh heavily on the likelihood of success there. Historically the city of Mosul was predominantly Kurdish. The city and the surrounding region had traditionally been considered part of Anatolia rather than Mesopotamia. It was a separate province (vilayet) under the Ottomans from the two provinces (Baghdad Vilayet and Basra Vilayet) that made up the historic region of Mesopotamia.

Under the Armistice of Mudros, between Great Britain and the Ottoman Empire, Mosul was to have remained part of Turkish Anatolia as the region was still controlled by the Ottomans when the armistice went into effect on October 31, 1918. British forces, however, spurred by the discovery of oil in the region, continued to advance for two more weeks after the ceasefire until they had secured Mosul and the surrounding region.

Mosul was part of the northern no fly zone enforced by the U.S. and Britain from 1991 to 2003. During this period, however, the Saddam Hussein government implemented an aggressive policy of "Arabization" that saw the government relocate large numbers of Sunni Arabs to the city and in some cases expel some of the non-Arab inhabitants. A significant portion of the senior leadership in the Iraqi Army came from Mosul, a fact that may explain how a significant number of former Baathist military and government officials have come to play a significant role in the administration of the city while it has been under IS control.

The Kurdistan regional government in Ebril has previously indicated that it would like to see Mosul included in the Autonomous Kurdistan Region. Such an outcome is highly unlikely, however. The Baghdad government would not want to see its second largest city incorporated into Iraqi Kurdistan. Its historical roots notwithstanding, the city is predominantly Sunni Muslim now. Moreover, it is likely that the city will suffer extensive damage during the military campaign and the tab for rebuilding it will amount to tens of billions of dollars - a sum beyond the means of the currently cash strapped Kurdistan regional government.

Disposition of forces in Iraq and Syria as of March, 2016What role the Kurdish Peshmerga forces will play in the battle for Mosul is unclear. Previously the Kurdistan regional government had announced that Iraqi military forces would not be allowed to enter in or operate from Kurdish territory. Moreover, the Kurdish regional government's financial constraints, and an unwillingness to spill Kurdish blood for what will ultimately be an Iraqi city, also means that the role of the Peshmerga will likely be to hold the current defensive positions to the east, north and west of Mosul, but not otherwise actively participate in the actual advance on the city.

The role that the Shia militias will play is also unclear. Previously, those militias and their Iranian sponsors had lobbied for an active role in the Mosul campaign. The Baghdad government has resisted a prominent role for the Shia militias fearing a repeat of the sectarian violence that erupted following the liberation of Tikrit. The situation with those militias is very fluid, however. The current Shia dominated government in Baghdad is badly fractured. A more prominent role for the Shia militias may be the price that the Sadr and other Shia political groups demand for their support of the government. At the moment, Shia militias are actively engaged against Islamic State forces in the desert areas surrounding Samarra, roughly halfway between Baghdad and Tikrit but do not appear to have a significant presence further north.

Moreover, if past experience with Islamic State is a guide, an offensive up the Tigris valley against Mosul will likely precipitate attacks by IS militants in the Euphrates Valley, especially in Sunni dominated Anbar province. Indeed the IS seizure of Ramadi in May 2015, was in part prompted by visible signs that Baghdad was readying a campaign up the Tigris Valley toward Mosul. It's unclear, and probably unlikely, that the Iraqi Army has sufficient strength to engage IS militants on both the Euphrates and Tigris fronts. Baghdad will likely have to rely on the Shia militias to deal with any new IS attacks on the cities in the Euphrates Valley. Depending on how extensive those attacks are, and the extent to which Baghdad is dependent on the Shia militias to contain them, may well determine whether those militias can successfully demand a larger role in the Mosul Campaign.

Baghdad is relying primarily on the U.S. trained Iraqi Army to lead the advance on Mosul. How effective those forces are going to be, however, remains unanswered. U.S. trained Iraqi Special Forces performed well during the Ramadi Campaign. The "Golden Battalion," the Iraqi 36th Commando Battalion, in particular, has received high praise from U.S. advisors. It is not clear yet whether Iraqi Special Forces are active in the Mosul campaign or are still deployed in mopping up operations around Ramadi.

Regular Iraqi forces, however, are still a question mark. There were numerous reports of Iraqi troops fleeing the battlefield during military operations against IS militants in the village of Nasr, south of Mosul, on March 25, when they came under prolonged sniper fire from IS fighters in the village. Adjacent Peshmerga units, most armed only with old Kalashnikovs and lacking the modern equipment of the Iraqi units, held their positions, on the other hand.

The same thing had happened a week earlier when Iraqi troops fled their positions defending a newly established U.S. Marines base near Makhmor. The facility, technically a firebase, was manned by 200 Marines from the 26th Marine Expeditionary Unit. The firebase is supposed to provide artillery support for the Iraqi troops clearing IS militants in the area and for the eventual advance on Mosul as well as to stiffen the resolve of the Iraqi military units, the 15th Division, in the area. One marine was subsequently killed when IS militants were able to approach close enough to the firebase to attack it with mortars.

What role Sunni militias will play in the Mosul campaign is also unclear. The U.S. has been urging the Baghdad government to organize and arm a Sunni National Guard, but the Iraqi government continues to be reluctant to do so fearing that such units would become the core of an armed Sunni resistance to Baghdad. Military equipment that the Pentagon has supplied to Iraq to arm a Sunni National Guard has instead gone to Shia National Guard units. The Turkish government has signaled that it sees a role for itself in training and arming Sunni militia units but is does not appear that it has moved to actively do so yet.

The likely response of Islamic State to the Mosul campaign will be fourfold. On the Tigris front they will adopt a scorched earth strategy relying heavily of IEDs and other types of booby traps to slow the Iraqi advance while engaging in a protracted street-by-street urban campaign within Mosul itself. In addition, they are likely to deploy insurgency tactics in the rear of the Iraqi forces advancing on Mosul. They are also likely to opportunistically bring pressure on the Euphrates front, especially in Anbar province, to tie up Iraqi troops and Shia militias and divert them from being deployed against Mosul. It is also likely that IS militants will single out captured Iraqi Army Shia soldiers for particularly gruesome executions as a way of reducing the military's morale.

Islamic State's propaganda magazine DabiqIS will also likely launch attacks against civilian targets in Baghdad and in the Shia dominated south. Already there are signs that this may be happening. Since February there has been a string of IS launched terrorist attacks in Iraq. These attacks have included two bombs that exploded at a market in Sadr city, a Shia suburb of Baghdad, on February 28, that killed 70 people, a suicide bomber attack during a funeral in Muqdadiya on Feb 29, an attack by four suicide bombers against an Iraqi military headquarters in Haditha on March 1, and a suicide bomber who detonated a bomb during a soccer game on March 25, in a stadium in Iskanderiyah, 30 miles south of Baghdad, that killed 29 people and injured 60 more.

Finally, although it will not deter the support provided by the U.S. and its allies for the Iraqi army, it is likely that IS militants in Europe, and even possibly the United States, will look to attack soft targets where the opportunity presents itself as a way of punishing U.S. and NATO support for the Iraqi Army. Over the last 18 months, the ability of Islamic State to stage sophisticated, well planned attacks against Western targets has improved significantly. On March 22, less than four months after similar attacks in Paris, IS militants launched a series of attacks in Brussels, at the airport and a subway station, which resulted in the deaths of at least 31 people and injured 250 others.

The campaign to retake Mosul is just beginning. Coupled with the losses that it is experiencing in Syria, we may well see the Islamic State lose all or most of the territory it controls in Syria and Iraq over the next 18 to 24 months. Such an outcome is far from certain, however, and it can be expected that IS will strike back wherever it can, especially at soft targets in Europe and the United States. Even if the campaigns in Syria and Iraq to roll back the Islamic State are successful, IS will remain a powerful international insurgency capable of continuing to strike at Europe and the United States, and is still actively engaged in Libya and some three dozen other countries around the world. Regardless of the additional defeats that the Islamic State may experience over the next 12 to 24 months, this is not the beginning of the end for the Islamic State, it is at the very best only the end of the beginning.