The forces from the Islamic State of Iraq and Syria are sweeping across Iraq. And even if the Iraqi army is able to stop ISIS's advance on Baghdad, the violent jihadist group will likely retain control of vast swaths of Iraq and eastern Syria.
In a matter of days, ISIS's bold and effective fighting in the heartland of the Arab world may have made it the pre-eminent force in the Sunni jihadist movement. It has now arguably eclipsed al-Qaida leader Ayman al-Zawahiri and his Pakistan-based terrorist core in the eyes of potential recruits and funders.
Indeed, unlike al-Qaida, ISIS is on its way to controlling a quasi-state, exercising de facto sovereignty over a territory, even if unrecognized by the international community. The territory already under its control is larger than Israel, and it is not some barren desert: It includes oilfields, electrical grids, prisons, small manufacturing centers and the weapon depots abandoned by the Iraqi military, including arms provided by the United States. When ISIS fighters conquered Mosul, they seized the central bank — and its reported $425 million. By comparison, al-Qaida's budget before 9/11 was about $30 million — and we called it rich.
Everyone agrees an ISIS-controlled state could be deadly — but in what ways? We typically think of terrorist outfits like al-Qaida and ISIS as nonstate actors. But what does it mean when a nonstate actor carves itself a state?
The disaster is worst for those unlucky enough to find themselves living under ISIS rule. The jihadist group's extreme ideology calls for killing or subjugating not only Christians and Jews, but also many Muslims.
Shiite Muslims, who make up a majority in Iraq, are particularly hated for their supposed apostasy, as are the Alawites who rule in Syria. ISIS also targets Sunni Muslims if the group believes that they are insufficiently zealous or have collaborated with the United States or its allies, including the current Iraqi government.
In Syria, ISIS members shot and then crucified the bodies of their Muslim enemies, leaving their corpses to hang as warnings. Beheading is common. "Repent or die" is its motto. ISIS is so violent, al-Qaida leader Zawahiri disavowed the group in February, excoriating it for its brutality and attacks against other jihadist fighters.
If it consolidates power in the territory it now controls, ISIS can exploit the rewards other governments enjoy. It will sell oil from the fields under its control, smuggling out what can't be sold legally. Millions will pour into its coffers.
It's hard to speak of an ISIS "foreign policy," at least in a traditional sense. Its central goal is the creation of an Islamic state — a goal it has sought to realize through brutality rather than diplomacy.
ISIS doesn't respect state boundaries, believing they are artificial creations of colonial powers designed to divide the Muslim world, so moving the front from Iraq to Syria and back to Iraq is logical from its point of view. Indeed, ISIS sees the struggles in both countries as parts of a larger grand struggle against apostate-dominated regimes (Shiite in Iraq, Alawite in Syria) backed by Iran and the Lebanese Hezbollah.
ISIS's control of territory gives it a base to recruit, train and plan attacks on neighboring lands. For now, because of its sectarian focus, ISIS sees the fight against those groups and governments it considers apostate as a higher priority than the fight against the United States, but the United States is also on ISIS's list of enemies.
Officials in Europe told me that some European Muslims are drawn to ISIS because they want to live in a real Islamic state — so much so they even bring their families with them.
Perhaps the biggest weaknesses for this newly minted jihadist state will be internal. The tribal and regional divisions that plague Iraq and Syria do not go away under ISIS any more than they went away under Syrian, Iraqi or U.S. control.
ISIS may be good at preaching fire and brimstone to motivate its followers to kill themselves and their enemies, but the bloodthirsty thug with an AK-47 isn't much good at helping you find health care or repairing your house after it's been shelled. It can loot and terrorize, but the patient work of providing services or otherwise running a country are beyond it.
So an ISIS-controlled state will not expand indefinitely, and it may prove even more fragile than what it has already toppled. What follows after jihadist state collapses? That may be a chaos we can't imagine.
Daniel Byman is a professor in the Security Studies Program at Georgetown University and the research director of the Saban Center for Middle East Policy at the Brookings Institution.
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