The crucial battle of Mosul has ground on for eight grueling months, uniting disparate factions in a desperate bid to undo the Islamic State's 2014 blitz. Now, the battle is coming to its final phase and that unity is under threat.
American Lt. Gen. Stephen Townsend recently said the battle was the toughest urban fight he'd yet seen in 34 years of service. Once a city of 1.8 million, the city has lost up to half its population as civilians fled and ISIS brutally ruled through executions and terror. Even for a country already scarred by wars going back to 1980, Mosul has been particularly jarring.
Iraqi forces, supported by American troops and Kurdish allies, have forced ISIS into the heart of the old city, a warren of ancient buildings sitting on a raised tell, a man-made hill formed over centuries of urban build-up.
ISIS forces are now entirely cut off, the Euphrates River to their backs while thousands of Iraqi armor, artillery, and special forces move into position.
BBC reporters Tweeted out some of the traps ISIS forces have utilized during the siege, including hidden tanks inside of civilian trucks. These booby traps are a large reason why the advance of up to 100,000 troops has been slow.
Yet there are deeper complications as the battle draws to a close. Many of the Iraqi forces taking part in the assault are Iraqi Shi'a, including militia who, a decade ago, were engaged in a civil war with Iraq's Sunnis. Mosul is a Sunni-majority city, while ISIS are Sunni supremacists. Concerns that some Shi'a might brutalize the conquered Sunni population have dogged the campaign. Most of the frontline troops are professional, non-sectarian forces, but in the aftermath of the American invasion in 2003, Iraq's armed forces have still not returned to their Saddam-era level of efficiency.Additionally, Kurdish forces across the river now guard a Kurdish enclave racing towards independence, despite Baghdad's objections. That vote won't be binding, but is meant to set the stage for negotiations with Iraq's central government over the future of Iraqi Kurdistan. Iraqi Kurdistan has been effectively independent since 1991, when a U.S.-imposed no-fly zone ended a post-Gulf War assault by Saddam Hussein's army.
Kurdish secessionism rattles Turkey, which has its own sizable Kurdish population, and which has been fighting a long-running war against Kurdish rebels since the 1980s. Turkey has invaded both Syria and Iraq to try to forestall the coming of an independent Kurdistan. The collapse of Mosul will break the united anti-ISIS front and force this simmering conflict to the surface.Finally, American troops have been warned off using phosphorus weapons in the final days of the battle by Humans Right Watch, who considers the use of the weapon a war crime. Phosphorus was reportedly used in the 2004 battle of Fallujah, when American Marines besieged the predecessor of ISIS, al-Qaeda in Iraq. The battlefield conduct of the allies will endure considerable scrutiny, possibly hampering operations against ISIS elsewhere.
Still uncertain is the status of ISIS's leader Abu Bakr al-Baghdadi, who Russian government sources claimed to have killed last week. Meanwhile, the allied siege of Raqqa, ISIS's capital, is progressing at pace, supported again by the United States. Regardless of what happens after, it seems the caliphate itself won't have much of a future.
[Featured image by Maya Alleruzzo/AP Images]