Mark Perry is the author of Talking To Terrorists. His new book, The Pentagon Wars, will be published by Basic Books next year.

One of the few pieces of good news coming from Iraq recently has been that the Iraqi army is winning the battle to retake Mosul from the Islamic State. A victory in Mosul, the nation’s second largest city and Northern Iraq’s most important industrial center, would mark the Islamic State’s most significant battlefield setback since the U.S. began targeting the group back in August 2014.

Iraq’s impending victory will be due almost exclusively to the Iraqi army’s elite 1st Special Operations Brigade, an American-trained counterterrorism unit of some 10,000 soldiers representing all of Iraq’s religious sects whose senior officers are graduates of the U.S. Army Ranger School. In mid-October, the elite Iraqi unit (called “the Golden Brigade,” but now referred to by Iraqis as “the Golden Division”), was designated as the lead unit in the fight to retake ISIS-held Mosul.


The U.S. has trained some 35,000 Iraqi soldiers over the past decade, but none as important as the Golden Division. The elite unit, which answers directly to the Iraqi prime minister, serves as a model for what the U.S. hopes the Iraqi army will become: well-armed, capably led, uncorruptible and and nonsectarian. Over the past year, the division’s soldiers have proved to be tenacious fighters, having led the successful fights to oust ISIS from Ramadi and Fallujah. Since the battle for Mosul began, the division has retaken the city’s eastern suburbs from ISIS in a grueling block-by-block contest.

But sources inside the U.S. Central Command tell me that this success has come at a terrible price, one that could have dire consequences for Iraq in the long run. With the division suffering “horrific” casualties every day, senior U.S. Centcom officers are worried that the grinding battle is slowly destroying the division itself. If that happens, which appears likely, Iraq will lose its best guarantee against civil war—the only force capable of keeping the peace when Iraq’s sectarian divisions, temporarily dampened by having to fight a common enemy, reemerge.

Put simply, the Golden Division’s fight for Mosul could go down in history as one of the greatest victories of the Iraqi government—and its last.

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Veterans of the 101st Airborne Division know Mosul well. The storied U.S. military division first came into Mosul after the fall of Baghdad in April 2003. Under the command of then-Maj. Gen. David Petraeus, the 101st transformed Mosul into one of the few American success stories of the war. “Money is ammunition,” Petraeus told his soldiers, and they passed it out freely, focusing on getting the city’s water, power and sewer systems back in operation. The spending was so lavish that Iraqis gave Petraeus, called “Peaches” by his West Point classmates, a new nickname: They called him Malik Daoud—“King David.” Building on that reputation, Petraeus became, for a time, America’s star general, the man who was said to know the secret to victory in Iraq.

It is a measure of how badly things have come apart in Iraq 13 years later that the city of 1.8 million is now unrecognizable to the 101st, whose 2nd Brigade Combat Team is advising the Golden Division in its battle against the 5,000 militiamen of the Islamic State for control of the city. The division is now two miles from the Tigris River, which divides Mosul in two—a significant advance from where the unit started when it began its operation on October 17.

The Golden Division entered Mosul having been hardened by fights against the Islamic State for control of Beiji, Ramadi, Fallujah and Bartella. No one doubts that the Iraqi army will reconquer this city too, but Mosul has been a different kind of a fight, with resistance tougher than any the elite Iraqi unit has previously faced. The neighborhoods of eastern Mosul, which have seen the most intense fighting over the past several weeks, have suffered the most, with ISIS suicide units packing explosives into trucks hidden in local garages, then driving them into Golden Division units and detonating them. One senior Centcom officer told me that ISIS has detonated over 600 suicide car and truck bombs since the start of the offensive. “We knew the fight for Mosul would be tough,” this Centcom officer said, “but it’s been a lot tougher than anyone thought.”

ISIS units have fought tenaciously, and few of its volunteers have been willing to surrender—even when facing overwhelming odds. And the ISIS command has maneuvered its units deftly, pulling its best combat formations back into tighter defensive lines closer to the city center when the pressure against them becomes intense. The result is that the toughest battles for control of Mosul have yet to be waged. “I had a good chuckle when I heard Ash Carter [the U.S. secretary of defense] say last week that ISIS’ ‘days are numbered,’” this Centcom officer added. “In fact, its months are numbered. This whole idea that the battle will be over by the time that Trump is inaugurated is a fantasy. This is going to go on for a long time.”

One senior Pentagon officer with access to daily battle reports on the Mosul fight says the battle for the city has been so intense that the Golden Division’s veteran battalions “are suffering upwards of 50 percent casualties. If that rate stays constant,” he told me, “the division could become combat ineffective in a little over a month, and perhaps even sooner.”

The division’s senior commanders certainly know this, and they are trying to minimize the unit’s casualties, which is one of the reasons their Mosul offensive has slowed over the past two weeks. In addition, senior Iraqi officers have apparently decided that instead of continuing to suffer the effects of battle attrition, they will rely on artillery, tanks or precision munitions from Iraq’s small arsenal of F-16s (the first ones were delivered by the U.S. in July 2015) to reduce ISIS units holed up in barricaded buildings, regardless of the likely presence of civilians. In fact, civilian casualties have continued to mount in the city due to air and artillery attacks, despite the efforts of U.S. Joint Terminal Air Controllers who paint targets for incoming F-16s, with the result that some of Mosul’s heavily populated neighborhoods northwest of the Gogjali industrial district have been reduced to rubble.

On December 7, Iraqi officials responded to the large number of Golden Division casualties by accelerating the training of replacements and by ordering other Iraqi units, including federal police formations under the command of the Interior Ministry, to fight their way to the Mosul airport on the Golden Division’s left flank. But the units have been slow to respond, in part because their commanders fear suffering the same high casualty rate as their elite counterparts.

As crucially, Iraq’s other major units (including the 16th Infantry Division, in the north) have been fought to a standstill, which means that the Golden Division will continue to carry the load.

A part of the problem, one Pentagon intelligence officer notes, is that the Golden Division’s battlefield competence means that it is the unit of choice for the Iraqi government, which views the battle for Mosul as a political as well as a military test—and a way for Iraq’s leaders to show off their new army’s combat prowess. “The problem with being the best is that you get used,” the Centcom officer told me, “and the more you get used, the more casualties you take and the duller you become.”

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Iraq’s Golden Division has a storied, and controversial, history. As one of three special brigades of Iraq’s elite Counter Terrorism Service, it acts under the direct command of Iraq’s prime minister. Established as a nonsectarian formation, the unit was first organized, equipped and trained by U.S. special forces units soon after Baghdad fell, with the express purpose of fighting the then-growing Iraqi insurgency. A select group of its best officers were brought to the U.S. for intensive training at the U.S. Army Ranger School, then redeployed to the division as combat commanders. From its earliest days its independent chain of command was resented, however, with Iraqis viewing the division as a political tool in the hands of the Iraqi prime minister. Among Iraqis, it became known as “the dirty division.”

But the Golden Division’s tenacious fight against ISIS over the past two years has burnished its reputation, giving it a gloss of respectability unequaled by any other Iraqi unit. The division’s newfound stature has also been a source of pride at Centcom, whose intelligence officers cite it as an example of the Army’s training expertise and as a counterpoint to America’s anti-ISIS fight in Syria.

At the heart of that comparison is the animus harbored by Centcom officers over the CIA’s failure to train a Syrian military equivalent. “All of this talk about how the CIA has put moderate Syrians in the field is a crock,” a joint staff officer told me last week. “The CIA program is a flat-out failure. The units we’ve trained are fighting in Mosul, while the units the CIA has trained are nowhere to be found. It’s an embarrassment.”

More crucially, the division’s new stature has raised hopes at Centcom’s forward headquarters in Doha, Qatar, that the unit can keep the peace in Iraq once the fight for Mosul is finished. After Mosul, one Pentagon intelligence officer reports, the nation’s Kurds, Shias and Sunnis will pick up where they left off before ISIS appeared: in a violent, bloody struggle for political power. The Golden Division has the training and the experience to form a bulwark against sectarian military units. But it also needs to remain combat effective, and that, given Mosul’s bloody calculus, is hardly a certainty. As a result, senior 101st Airborne commanders have been trying to shift the burden for the Mosul fight to other Iraqi units, but without much success.

Centcom planners, I was told, had hoped that ISIS units embedded in Mosul would flee west along the highway leading to Syria, where they could be slaughtered by U.S. and coalition aircraft. But so far that hasn’t happened: While some fighters have fled, not only have the majority of ISIS main-force units remained in the city, the main road west has also been closed by the Iranian-supported Hashd al-Shaabi, the Iraqi Popular Mobilization Units (the PMU). In mid-November, Hashd al-Shaabi overran Tal Afar airport, near Iraq’s border crossing with Syria. For Centcom senior officers, that was good news (ISIS is now surrounded) and bad news—with no way out, ISIS units in Mosul will now fight the Golden Division to the last man.

An additional complicating factor for Centcom military planners is that a part of the 101st’s replacement unit, the 1st Infantry Division, has recently been subject to a controversial change in command, with Maj. Gen. Wayne Grigsby dismissed as the unit’s commander “due to loss of confidence in his ability to lead,” an Army spokesman announced in September. The Army has not announced why Grigsby was relieved, but one senior civilian Pentagon official told me that Grigsby’s mistake was in inviting retired Lt. Gen. Jerry Boykin to speak at a Fort Riley, Kansas, prayer breakfast in June. Boykin is known for his anti-Muslim sentiments,, and for saying that Jews are responsible for the world’s problems. Grigsby rescinded the Boykin invitation, but apparently not in time to save his command position. “You can’t have a guy in charge of a unit in Iraq who is associated with someone who says that Muslims are the spawn of Satan,” the senior Pentagon civilian told me. “Wayne was a hell of a combat officer, but what the hell was he thinking?”

The result of all these factors is that senior U.S. military officers have accelerated their planning for “the day after”—for what happens after Mosul falls. Centcom commander Army Gen. Joseph Votel, picked to head up Centcom by President Barack Obama because of his special operations expertise, believes the outlook is dark, this same Pentagon intelligence officer told me, and likely to get darker, with the country heading inexorably toward a civil war. Votel’s worries have been heightened by military intelligence reports tracking increased Saudi arms shipments to Anbar’s Sunni tribes, in apparent preparation for the inevitable face-off against the Iranian-supported Shia PMUs.

“The White House always worried that arming the tribes would fuel a Shia-Sunni civil war,” this Centcom intelligence officer told me, “but the Saudis have no such compunctions. It’s a problem, a big problem, because arms are flooding into Anbar and have been for the last several months. Everyone is getting ready for the reckoning.”

Watching this from Centcom headquarters in Tampa, Florida, and from Centcom’s forward base in Doha, Votel has been communicating his worries to Washington, along with his own assessment—that once ISIS is chased out of Iraq, America’s best option will be to get out of the line of fire, as the Shia-dominated militias face off in a war against Anbar’s Sunni tribes. In that fight, the Golden Division, a symbol of the new nonsectarian Iraqi army, will not be able to intervene to stop the fight—let alone dictate its outcome—as it’s likely that by then it will have lost its best fighters in the streets of Mosul.