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The battle for Mosul, explained

An Iraqi soldier outside of Mosul.
(Marwan Ibrahim/AFP/Getty Images)
Zack Beauchamp is a senior correspondent at Vox, where he covers ideology and challenges to democracy, both at home and abroad. Before coming to Vox in 2014, he edited TP Ideas, a section of Think Progress devoted to the ideas shaping our political world.

In June 2014, ISIS stunned the world by seizing Mosul, Iraq’s second-largest city. It was touted as proof that this group was a new kind of terrorist threat — one that could take and hold territory. Shortly afterward, ISIS leader Abu Bakr al-Baghdadi declared his territory to be a caliphate, the Islamic State, at a speech in Mosul — the caliphate’s crown jewel.

Now Mosul is the last major Iraqi population center under ISIS control, with all others having already fallen to Iraqi government forces. And Monday morning, the Iraqi government finally launched an offensive to retake the city from the Sunni jihadists — an offensive that, according to experts, is quite likely to succeed.

“Do they [ISIS] have a chance of holding the city in the long term? Zero,” says Daveed Gartenstein-Ross, a senior fellow at the Foundation for the Defense of Democracies (FDD).

Facing overwhelming odds, ISIS is in the throes of an existential crisis: Can it survive an assault on the site of its greatest victory?

Why Mosul matters

Mosul is highlighted in red.

Mosul is, by far, ISIS’s most important holding in Iraq. Home to a prewar population of more than 2 million people, Mosul has Iraq’s largest Sunni population hub in a country that is politically dominated by a Shia majority. As long as ISIS controls Mosul, it will by definition control a significant part of Iraqi territory. ISIS cannot be considered defeated in Iraq, full stop, until Mosul falls.

Mosul is also a big deal in practical terms. Much of ISIS’s revenue comes from extorting and taxing the people who live in its territory. When it loses a large population center, it loses a lot of people to steal from. ISIS’s chemical weapons production is also predominantly centered in Mosul. Finally, Mosul is in a very important strategic location, as the city controls access to the surrounding area, including north into Kurdish Turkey, east into Iran, and west into Syria.

The city is also a key part of ISIS’s legitimacy. Since 2014, ISIS has had one core message: It is the sole legitimate Islamic government in the world. The key word there is government: ISIS set itself up not just as an ordinary terrorist group but as an actual state. In order to be a state, you need to actually govern territory where people live.

This was a core part of the group’s recruiting pitch to militants around the world, and the main feature setting it apart from its rival jihadists in al-Qaeda. Al-Qaeda has long argued that the dream of an Islamic caliphate cannot be realized until the stage has been properly set and the forces that would try to destroy it (such as the United States) have been defeated. Then, and only then, could a caliphate have a chance of surviving.

The leaders of ISIS, on the other hand, believed the caliphate could exist and flourish right now, and they set about making that happen. For a while, ISIS seemed to be succeeding, as the group took over more and more territory and thousands of Muslims from around the world flocked to Iraq and Syria to help build the new caliphate.

But 2016 has been a disastrous year for ISIS in Iraq. In January, it lost Ramadi, the provincial capital of the western Anbar province. In June, it lost Fallujah, the Iraqi city it had held longer than any other. By July, it had lost 12 percent of the Iraqi and Syrian territory it had controlled at the beginning of the year. Now Mosul is the end of the line. If Mosul falls, ISIS will be proven wrong, and al-Qaeda will be proven right.

“This is the last major urban area that ISIS holds [in Iraq],” Douglas Ollivant, the former US National Security Council director for Iraq, says. “After Mosul, it’s all one big mop-up operation.”

The Iraqi army is in a very strong position — because ISIS is weak

Destroyed ISIS car (Ahmad al-Rubaye/AFP/Getty images)

ISIS’s two-year grip on Mosul has given the group time to prepare for the coming onslaught, reportedly digging trenches and tunnels to slow the Iraqi ground advance and preparing smoke screens to block out coalition warplanes’ visibility. Retaking the city, as Austin Bodetti writes for Vox, could end up being time-consuming and bloody, taking months and claiming a significant number of lives.

But experts on Iraq say that in the end, the Iraqi army is overwhelmingly likely to retake the city from ISIS.

“The outcome’s not in doubt,” says Michael Knights, the Lafer fellow at the Washington Institute for Near East Policy and an expert on the Iraqi military.

According to Knights, the main body of the Iraqi force is 44,000 strong. These fighters include Iraq’s elite special forces fighters, called the Counter-Terrorism Services, and Sunni tribal militia fighters well-positioned to work with the local population.

They are buttressed, per Knights, by about 4,000 Kurdish peshmerga and 2,000 to 4,000 Shia militia fighters (who will be playing a minor supporting role). The American-led anti-ISIS coalition will contribute air power and artillery and help coordinate logistics and planning for the operation.

“We haven’t done anything this big in Iraq — and I mean ever,” Knights says. “The last time this many Iraqi troops were moving, they were invading Kuwait.”

Estimates of the ISIS force in the city, by contrast, range from 1,000 to 6,000. Those are just very, very long odds.

“It’s such a big city that they’re going to be spread very thin if they try to defend the whole city,” Knights says. “Every day the battle rolls on, more and more [ISIS fighters] are going to leak away ... to fight again or just escape and live.”

ISIS was able to beat those odds when it took Mosul in June 2014. But it is facing a far different enemy today than it faced two years ago. When ISIS first rolled into Mosul, the group had momentum, and the Iraqis were too weak and divided to stop it. Today, though, ISIS is besieged on all sides by a much more robust coalition of forces backed by US air power.

“They are significantly better,” Ollivant says. “Are they the US military? ... No. Are they good enough to beat ISIS inside Mosul? Probably.”

In the face of this offensive, ISIS has basically two options. It could fight as hard as it can with its most committed troops, essentially making it a vicious block-to-block affair. Or it could put up a less stiff fight, and have its fighters withdraw to the Iraqi countryside and its Syrian “capital” of Raqqa.

According to Knights, there are already some reports of withdrawals to Syria, but it’s hard to confirm that for sure. Whichever option ISIS chooses carries serious perils with it.

If the group choose to stand and fight, the risk of a humanitarian crisis gets even higher. According to CNN, roughly 1 million people still live in Mosul and are already suffering due to ISIS mismanagement. No matter what happens, the situation for Mosul’s civilians is likely to be bad. But the more protracted the battle for the city is, the greater the risk of a humanitarian catastrophe.

If ISIS chooses to withdraw in large numbers, then the task of defeating the group in the long run could actually become harder. After Mosul falls, and the immediate urgency of the ISIS fight fades, it’s not clear how effective the Iraqi government and military will be at rooting out ISIS fighters who have chosen to hide, setting the stage for further violence.

The Iraqi government is already deeply divided across a number of sectarian, political, and ethnic lines — and its military is notoriously bad at working with Sunni civilian populations.

The bottom line, then, is that liberation is likely — but that doesn’t solve all of the city’s problems, or Iraq’s. Not by a long shot.

ISIS’s existential crisis

ISIS Propaganda
Not so much with the “victorious,” actually.

Mosul is the most significant example of ISIS’s military troubles, but hardly the only one. Virtually everywhere, the group is losing territory and resources, its once powerful caliphate a shadow of its former self.

In Syria, Turkish-backed rebels just captured Dabiq, the town in which ISIS claimed it would win an ultimate, apocalyptic battle (oops). In Libya, government-aligned fighters are on the verge of seizing ISIS’s remaining territory in the city of Sirte, the militant group’s former stronghold in the country.

Even Raqqa, the so-called “capital” of ISIS’s caliphate in Syria, is at major risk. Kurdish troops have been camped out mere miles away from the city for months, with ISIS powerless to repel them. The US and its allies are reportedly organizing an offensive against it. While the challenges facing the Iraqi government after the fall of Mosul are daunting, the challenges ISIS’s territorial empire faces are graver still.

“They’re in a lot of trouble as a governing entity,” Gartenstein-Ross, the FDD scholar, says. “They reached a state of collapse.”

With its territorial holdings in rapid decline, ISIS is facing something of an existential crisis: What is the Islamic State if it doesn’t have a state?

The most plausible result, according to the experts, is that ISIS’s leadership tries to fade into the shadows, continuing to plot terrorist attacks both in the Middle East and globally without controlling territory in the way it has in the past.

ISIS is a terrible state but a highly effective terrorist organization, one that has been pulling off major attacks in Iraq and elsewhere since 2003. Back then, the group was known as al-Qaeda in Iraq — and even managed to hold significant amounts of Iraqi territory by 2006.

When that territory was nearly entirely retaken by the US and its Iraqi allies in 2009, AQI leadership regrouped, reforming as a terrorist organization and ultimately reemerging as ISIS in 2013. The obvious next move for ISIS is to do something similar again, under either its own name or a new one.

“The most likely outcome [is] ISIS 2.0,” Ollivant says. “[It] goes back to its core competencies of terrorism, insurgency, bombings, random acts of violence, inspiring franchises, and lone wolf attacks.”

But it’s not obvious that ISIS can do this again. There’s a chance that if the battle for Mosul goes as expected, the group will eventually fade away, even if it tries to reform as a terrorist group.

The basic reason is its caliphate branding. For the past two years, ISIS has been in a major competition with al-Qaeda for recruits and money. ISIS’s core argument in that disagreement boiled down to “we have a caliphate, and you don’t.”

But after Mosul falls, ISIS may not have a caliphate for much longer. This suggests that the group’s claim to be the infallible, inviolate kingdom of God prophesied in early Islamic texts is implausible, to say the least — and that maybe al-Qaeda had it right all along.

“They will have declared a caliphate and then lost it,” Ollivant says. “It strikes me that this then lowers their credibility relative to other, similar groups. ... It’s likely that ISIS fades, and al-Qaeda and the various al-Qaeda affiliates resurge.”

So it’s possible that the loss of credibility, as well as loss of tangible resources that come from controlling territory, leads the group to fall into infighting or simply collapse.

“There’s a chance that ISIS will experience a complete brand reversal and its organizational structure will crumble,” Gartenstein-Ross says. “You can’t be the once and future caliphate.”

This is ISIS’s existential crisis, and has been for some time as its caliphate has begun to shrink. The offensive on Mosul has just made it acute — putting serious, serious pressure on the so-called Islamic State.

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