On the Front Line Against ISIS: Who Fights, Who Doesn’t, and Why

An in-depth report on the inconclusive battle to take one small village exposes the weakness of the strategy to retake Mosul, Iraq’s second-biggest city.

Karim Sahib/AFP/Getty

KUDILAH, Iraq — It is April, and fighting is stalled, with part of the Iraqi army forces camped at the village of Kudilah and unable to advance because of fierce resistance and counterattacks by the so-called Islamic State. The research team that first came here in February to talk to fighters on all sides about a ferocious battle that was supposed to be over, or at least ending, is continuing its interviews. Our aim is to better understand the “will to fight.” President Barack Obama and his National Intelligence Director, James Clapper, have called this “the imponderable” that has led to an overestimation of the allied ability to degrade and destroy Islamic State forces and an underestimation of their ability to resist.

At Kudilah, fighters from the Islamic State (also known by the acronyms ISIS, ISIL, and Daesh) are pitted against Arab Sunni tribesmen along with Kurds of the Iraqi Army and the Peshmerga of the Kurdish Regional Government.

American and German military advisors and contractors planned the battle, in part, to test out the coalition of forces needed for the eventual assault on the nearby city of Mosul, the second biggest metropolis in Iraq and by far the largest population center under ISIS control anywhere.

So the Battle of Kudilah, we believed, would provide a laboratory-like setting for some of our psychological and anthropological studies looking at morale and commitment.

What is it that links the recent attacks in Paris, San Bernadino, and Brussels to this remote battle in northern Iraq that nearly everyone involved (Peshmerga, Iraqi Army, Sunni Arab) describes as the fiercest of their lives? Why do so many young people leave home and family, endure hardship and pain, to kill as many “non-believers” as possible, whether in battles along a front more than 3,000 kilometers long in Iraq and Syria or in more than 50 terror attacks in 20 countries since ISIS took Mosul and declared itself The Caliphate? And can the cobbled-together U.S. coalition of ground forces take Mosul back?

The fight over little Kudilah, which initially involved maybe 700 combatants in and around a village with only about 150 houses, may tell us a lot about the shape of things to come.

The battle was barely noted in the international press, and to the extent it was, only the initial victory over ISIS was reported, even after ISIS took Kudilah back.

What was striking was the lack of coordination and commitment among the anti-ISIS coalition versus the heartfelt determination of ISIS to hold Kudilah at all costs.

This was not our first visit to these front lines. We had done fieldwork in another village, Rwala, last year. Soon after our arrival this February, we learned it had been hit by a chlorine gas attack. ISIS often uses chemical weapons improvised or captured from one or another undeclared government stockpile. Last year it hit the village of Aliawa with 48 Katyusha-type rockets carrying mustard gas. It was impossible to know when the next rain of poison would begin.

The history and the geography in this region is vital to any understanding of the will to fight.

If you look back to August 2014—less than two years ago, it is worth noting—ISIS looked like it might just be unstoppable. It had taken Mosul in June, virtually without a fight, and now it was rolling across northern Iraq. To the south and east, its fighters crossed the Tigris River, reaching the town of Makhmour. Further north, they pushed across the Great Zab River, a Tigris tributary, at Gwer (also known as al Kuwayr).

ISIS was now within striking distance of Erbil, the capital of the Kurdish Regional Government of Iraq (KRG), a quasi-state wrenched from Saddam Hussein’s control and established in 1992 under America’s “No Fly Zone” following the first Gulf War.

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Many of Erbil’s half-million residents began to flee the city, keenly aware of how quickly ISIS had been able to take Mosul, despite being outnumbered more than five to one by an Iraqi army trained and equipped by the United States.

But the Kurds and Christians of Erbil were even more frightened by reports from the ongoing ISIS encirclement of Mount Sinjar to the west. The Kurdish Regional Government’s vaunted Peshmerga forces had cut and run rather than defend the religious minority known as Yazidis.

That left ISIS free to exterminate Yazidis, whether by automatic weapons fire, or beheading, or burning them alive, or tying them to two cars and ripping them apart. At the same time, ISIS hunted down Yazidi women to use and sell as slaves while letting the children and elderly who fled up the mountain die daily by the hundreds because of dehydration.

At one point, KRG President Masoud Barzani, who also heads the Peshmerga forces, told U.S. Central Command that it was only a matter of hours before Iraqi Kurdistan fell, and with it perhaps all of Iraq.

President Obama, pulled from a D.C. restaurant where he was dining with his wife, was told that unless U.S. air power entered the fray immediately the whole region could be lost. The only forces not in full retreat were Turkish Kurds of the PKK, a Marxist-Leninist group that’s on the U.S. list of terrorist organizations, which pushed to the front of the line near Makhmour, and the PKK’s Syrian affiliate, YPG, which was punching a narrow corridor through ISIS lines from the Syrian border to Mount Sinjar in the west in a heroic effort to save the besieged Yazidis there.

By the time our research team first arrived in Iraq in early 2015, Makhmour and Gwer (Kuwayr) were again in Kurdish hands and the front had stabilized a few kilometers to the west thanks to American and French air power. Air cover had enabled the Peshmerga, which had been a formidable mountain fighting force prior to the KRG’s establishment, but in the interim had become largely an inert group on the dole, to adapt to unfamiliar fighting conditions on the flat plains of Mesopotamia and to reaffirm their fighting spirit.

Many Peshmerga whom we interviewed and tested in psychological studies on “the will to fight” had been wounded, some multiple times; yet even veterans without limbs and older volunteers who had first joined the Peshmerga in the 1950s were fighting at the front. They were ready to die for an idea they called “Kurdeity,” which Kurdistan’s borders existed to protect. The Kurds had become the most effective fighters by far on the ISIS frontier, but they functioned more like sentinels than a vanguard pushing ISIS out of non-Kurdish areas.

By the beginning of our second visit in February this year, nearly all of Mount Sinjar and its surroundings were in Kurdish hands, through a combined effort of Peshmerga, PKK, YPG, and recently formed Yazidi militia.

Kurdish forces now seemed poised to spearhead efforts to retake Mosul. Together with newly gathered Iraqi units of Kurds, Sunni Arab, and Shia camped near Makhmour and Gwer, they could advance on Mosul while cutting off ISIS’s retreat from Sinjar, which dominates the main road between Mosul and Raqqa, the ISIS capital on the Euphrates in Syria.

Our second visit to the Makhmour front came two weeks week after the battle for Kudilah, about 2.5 kilometers from the forward Iraqi army outpost known as Burj.

American military advisors and contractors, with a handful of German soldiers, had drawn up the battle plan in collaboration with sheikhs from neighboring Sunni Arab tribes whose lands were in ISIS hands. The real danger, Peshmerga told us, was that fighters from the so-called Islamic State could position 57 mm guns on Kudilah’s high ground, dominating the chokepoint on the road between Makhmour and the Tigris that is the only supply route for dozens of ISIS-held villages in the sector.

The sheikhs told the Americans that they could take and hold Kudilah with American air power to back them up, and then perhaps advance as far as Qayyarah by the Tigris. The Americans wanted the Peshmerga and Iraqi army units (consisting mostly of Kurds) to hold back at the outpost and other points in the rear unless things went bad.

The U.S. advisors at the military center in Makhmour (dubbed “Camp Coca Cola” by some) wanted to show that a year of training these anti-ISIS Sunni Arab tribesmen was paying off, and that they could re-establish themselves when the time came to retake the mostly Sunni Arab city of Mosul and its surrounding lands.

The lack of senior American military personnel on site, and the outsized role of contractors-for-profit with little evident cultural knowledge or field experience in this particular theater wasn’t supposed to be a problem (although even experience with the rugged mountain tribes of Afghanistan counts little for managing tribes of the Mesopotamian plains).

The sheikhs wanted to show that they could take back their villages from ISIS even though many of their fellow villagers and tribesmen were fighting alongside ISIS. Our interviews with them made it clear that they, along with the overwhelming majority of Sunni Arab tribesmen, had initially welcomed ISIS as a revolutionary movement that could take Baghdad from the Iranian-backed Shia; but support had soured when ISIS began taking their power and property away, and killing anyone who objected.

The story of intrigue and collaboration did not end there, however. Many Sunni Arabs still supported ISIS as an ally while acting on their own rivalries, jealousies, and grievances. Others were trapped in its service. Friends and relatives were often pitted against one another.

Because of ISIS’s policies of killing and dispossession, the differences in allegiance now transformed into a deeper moral and mortal conflict. As one Sunni Arab sheikh who fought at Kudilah told us: “Daesh [ISIS] had my friends call me from my town, saying I should come back and work for the revolution because I was a leader who the people trust. But I knew from others that the plan was to kill me.” Another of the sheikhs stayed about 10 days with ISIS but fled when someone said ISIS was coming to execute him: “We were happy when Daesh came. We thought they were going to Baghdad to establish a government. But then they started killing our own people.”

From the outset, the Peshmerga and Iraqi army forces were skeptical about the American plans and the sheikhs’ ability to deliver. But the Kurds of all ranks—from government leaders, to commanding officers, to foot soldiers—say that they have no desire or intention to advance into Sunni Arab lands beyond what they consider to be the natural boundaries of Kurdistan, roughly their current front line of mud wall and ditch stretching 1050 km across northern Iraq from Syria to Iran. They could help in an offensive to retake Sunni Arab lands, but not lead or stay.

The fight for Kudilah began under cover of fog early the morning of Feb. 3 with bombardment by American war planes and with 120 to 150 Sunni Arab tribesmen advancing against 90 to 100 entrenched ISIS fighters (formed in three groups of about 30 fighters each, according to listings of names and weapons taken off a dead ISIS commander).

But the tribesmen were stopped a few hundred meters outside Kudilah by improvised explosive devices (IEDs) and drew back. Meanwhile, an Iraqi army unit under a Major Amin, called “the Group of Fire,” began advancing from the forward outpost at Burj towards Kudilah with 40 men in a Badger Combat Vehicle, four Hummers, and two jeeps, followed closely by 200 Peshmerga in a column of two Badgers and some 20 Hummers (captured from ISIS, which had previously captured them along with about 1600 other American-made Hummers from mostly Sunni Arab forces of the Iraqi army).

ISIS sent four suicide car bombs to stall the advance: coalition planes knocked out two, a French-made Milan anti-tank missile hit another, and the fourth blew up before engaging. Peshmerga cleared the village by noon, then withdrew to the rear after deploying Sunni Arabs throughout the town. Major Amin’s forces stayed through the night, clearing some 80 IEDS to secure the approach between Kudilah and the Burj forward outpost.

Between 9 and 10 p.m. the next evening, ISIS launched a counterattack spearheaded by up to 17 inghamasi, (“those who dive in deep,” fighters wearing suicide vests who often lead the attack), killing five Arab tribesmen and wounding several other Arabs while taking one of Kudilah’s two positions on high ground.

According to one of the sheikhs who led the initial coalition attack on Kudilah, “most of the inghamasi were from the Caucasus, they had no beards, no hair.”

One suicide attacker, identified by ISIS reports as Mahmoud Lhebi, blew himself in an embrace with a coalition soldier. He was from the sheikh’s tribal faction, and the sheikh did not mince words: “He was the son of a whore, a slut. Two men were killed because of her. When her husband found out about the man she was screwing he killed the man, and the man’s family killed the husband. That’s who joins Daesh!”

In an earlier interview the sheikh had said: “We are sure that a lot of the people who are fighting with Daesh now come from our tribe. I am sad for this situation, but they chose the wrong path.”

Nearby soldiers from the Iraqi army said that the Arab tribesmen at first stood their ground but “fired wildly,” without much discipline or direction, until their ammunition ran out and then they skedaddled.

At first, Major Amin’s men thought the pickup approaching them without lights was an SVBIED (Suicide Vehicle Borne Improvised Explosive Device), but realized at the last moment that it was the sheikh’s car, which carried one dead and two badly injured. “The sheikh was disoriented,” said Amin, “worried Daesh would behead him. But I calmed him down and we went back with my men to the three houses” on the other high ground position.

The sheikh tells a somewhat different story, claiming that it was the Americans who let him down at every turn. “Look what they gave me!” he said, shouting at one of his men to “bring that lousy Egyptian Kalashnikov.”

“They gave me 125 of these Kalashnikovs, 13 BKC [7.6 mm Russian-made machine gun] and five pickup trucks that bullets can penetrate easily. Most of the guns don’t work. I’ve spent about $50,000 buying weapons and ammunition [he showed a list totaling $49,500]. The battle cost me a lot.”

The sheikh also mentioned that ISIS used his relatives as human shields. But he was most bitter about the American planes’ failure to bomb ISIS targets:

“I moved one of my pickup trucks a few meters and immediately got a call from the coalition coordinators telling me to pull back the vehicle. So how come they can see my pickup move a few meters but not Daesh suicide vehicles? I told the coordinators ‘There’s a jet above, please tell it to bomb the Daesh position.’ But I was told that the jet had run out of ammunition… We did run out of ammunition. I told my men to retreat, they didn’t want to leave, but I ordered them. Some were crying because they didn’t want to go.”

The sheikh clearly believes the U.S. is not serious about defeating ISIS because it wants to keep the Sunni Arab world divided and weak. Many, if not most, of the Peshmerga also see Washington as somehow complicit in keeping ISIS afloat—even those who want the U.S. to take a more active role—but for different reasons: “Why does America give all the help to the Iraqi army? Why do its planes come late and miss Daesh targets? Why can’t the greatest power on earth simply finish them off?”

The Kurdish answer to that rhetorical question is that the Americans want to keep the Kurds as weak clients, whether in cahoots with Turkey or Iran or just to keep their boot on the region. Conspiracy theories abound here, and all the moreso if they have some apparent grounding in reality.

ISIS soon occupied most of the village. The remaining Sunni Arab forces withdrew, fighting a rearguard action. Peshmerga moved back into the village and by 11:30 p.m. it was relatively quiet. A Peshmerga leader then escorted the local press into Kudilah to witness the “victory.” He said that neither the Sunni Arabs nor the Iraqi army units were able to hold the village because of “lack of experience,” which chagrined the Arabs and infuriated the Kurds of the Iraqi army.

“We were dead tired from the fighting,” said one of Amin’s men, “we didn’t care about the press because all we wanted to do was rest our backs against the wall. My brother telephoned to tell me about the news report. I fumed.”

The conflict in this battle was not just between coalition forces and ISIS, but also, and perhaps even more ominously for the future, within the coalition: historical quarrels and rival ambitions rose to the surface, with conflicting claims of victory, cowardice, and a keen sense of betrayal among the three major forces (Iraqi Army, Peshmerga, Sunni Arab). There was also a conflict of identity between Iraqi Army Kurds and KRG Peshmerga: “We want to know, are we Iraqi Army or Kurdish Peshmerga!” Amin shouted to a KRG Peshmerga the next day after the initial fight. (Amin and his men were regular Peshmerga until billeted to the Iraqi Army in 2004 under an agreement with the KRG brokered by the U.S.-led coalition government.)

When the Peshmerga started to move out with the press, the Iraqi Army units also began to withdraw. ISIS saw the opportunity and attacked in force from two nearby villages at around 12:30 a.m., Feb.5. Peshmerga forces turned around, but were pinned down near the village entrance by intense ISIS fire that included mortars, rocket-propelled grenades (RPGs), Soviet-era heavy machine guns (Doshkas), as well as rifle fire.

Amin, who hadn’t yet left the village, reported the situation to General Sirwan Barzani, overall commander of KRG forces on the Gwer and Makhmour fronts: “I ask you to go back and try to hold,” Barzani said, “but only if you are sure you won’t fall into Daesh’s hands.” Amin and a few men in his unit raced back to the houses on the high ground and were soon surrounded.

During the next few hours, Amin and company resisted with almost unimaginable courage. Cut off from their main force, they fought nonstop until nearly out of ammunition, when a Peshmerga captain whose name, Sherdl, actually means “Lionheart,” stormed into the surrounded position with a Hummer and a box of ammunition, and joined Amin on the roof of the only building that was still held but under relentless fire.

“I found out the others were already reciting the prayer of the dead for us,” said Amin, “when Sherdl came.” Said Sherdl: “It was very bad and I thought Daesh could break through to Makhmour. I had to try to help my comrades.”

A lone soldier guarding the house, name of Shkak, dashed with the ammo box into a recently dug grave near where his friend Zuber had fallen dead, before sprinting to the Badger where Karzan, the gunner, held off ISIS fighters as close as 18 meters away, apparently killing five of them. American drones tracked the fighting but the opposing forces were too close to each other—never more than 120 meters apart—making an aerial bombardment too dangerous.

As Karzan tells it: “Daesh was shouting its war cry: ‘The Islamic State is enduring and expanding! We will behead all you infidels and apostates!’ That cry brings fear to the heart.”

But Karzan taunted back (as his comrades confirm): “I swear to God, I will kill you one by one!” while ululating like Arab women at a wedding “to drive Daesh crazy.” Other Kurds hooted: “Daesh, you are only the State of Sex Maniacs!” (dawla seksiyya instead of dawla islamiya, the Islamic State).

Amin telephoned headquarters at Gwer: “I’m finished unless you come now.” Captain Taha, who had rushed from his home to gather Iraqi army reinforcements (40 men in three hummers and a pickup) broke through to Amin just as all appeared lost: “My vehicle was hit five times,” said Taha, “Daesh was yelling ‘Allahu Akbar [God is Great]’! I was yelling Allahu Akbar! God only knows who is right.”

Another 20 vehicles, mostly pickups, and 100 to 200 Iraqi Army forces followed about an hour later. By 4:00 a.m. Kudilah was again in coalition hands as ISIS fighters fell back to the two nearby villages of Mahane and Kharbadan.

According to Peshmerga Brigadier General Ziryan, deputy commander of the Makhmour front, there were 52 confirmed ISIS dead, mostly from coalition airstrikes, and an undetermined number of wounded in an ISIS force estimated at no more than 100 fighters.

One wounded 15-year-old ISIS fighter was taken alive, but we couldn’t find out anything about him as KRG intelligence whisks away captured fighters who are not immediately executed into some dark hole. Gen. Ziryan, who had been fighting since the 1970s against Saddam Hussein and successive threats, told us that fending off the ISIS counterattack was the hardest battle he’d ever fought. “The Daesh emirs [leaders] fight until they die,” Ziryan said.

As Karzan put it: “They were coming at us full of heart, with full commitment to their beliefs. It was much more vicious than Fallujah or Ramadi. ‘Death or victory.’ They would not retreat until our reinforcements overwhelmed them.”

“And then,” said Shkak, “I heard the explosions of five or six or seven inghamasi who blew themselves up to cover the retreat. It’s hard to know anything for sure in the fighting all around you.”

The battle seemingly was won. But it wasn’t.

Coalition forces could hear Abu Ali, commander of the ISIS forces in the battle, exhorting his soldiers over the walkie-talkie to retake Kudilah from the Crusader Coalition at all costs on direct orders from Caliph Abu Bakr al-Baghdadi.

The fierce determination of ISIS soldiers to fight on against overwhelming force ultimately convinced the Sunni Arabs not to redeploy in Kudilah without the continued presence of the Iraqi Army, which was ordered to withdraw, or the Peshmerga, who didn’t want to occupy an isolated position surrounded on three sides by ISIS-held villages, however strategically important. And so the Arab tribesmen withdrew as well.

The Islamic State’s local news bulletin, Al-Naba Wiliyat Dijlah, announced: “After vicious fighting with Peshmerga apostates and the Rafidhi mobilization forces [a reference to mostly Shia militia that did not in fact participate in the fight but are seen as the tail wagging the Iraqi army]… and intense air cover from the coalition of crusaders, the soldiers of the Caliphate managed, praise unto God, to wage a counterattack that led to re-control [of Kudilah] at dawn of Saturday Rabia’ al Akher [Feb. 6] after two days of heavy fighting.”

According to discussions with U.S. military commanders in Iraq, plans to retake Mosul call for eight to 12 combat brigades (up to 50,000 soldiers or so). These troops would outnumber the estimated ISIS force in Mosul by more than 5 to 1. But unless there is fighting spirit and coordination in the Iraqi Army from the squad level on up, the troops won’t be enough.

It may be wishful thinking to believe that U.S. advisors will make the “massive difference” that some “Iraq experts” suggest. As retired army Lt. Col. Daniel Davis writes in The National Interest: “It is clear that the problems with the Iraqi Army’s disintegration in 2014 when confronted with ISIS, and the conditions affecting the future battle for Mosul, go far deeper than anything a handful of U.S. military advisors are going to solve.”

From the road connecting Makhmour to Aliawa we can see the camp for the Iraqi Army’s 15th Division being set up for the advance on Mosul. Currently designed for 4,500 soldiers, it will likely grow.

ISIS targets the camp frequently. At dawn on March 15, ISIS took advantage of fog and rain to launch a suicide attack. Three ISIS inghamasi rushed the gate; two were killed before reaching it; a third blew himself up at the gate, wounding four soldiers.

At dawn on March 21, five inghamasi died on their way to the camp along with two Iraqi soldiers. General Najat Ali, the Peshmerga commander of the Makhmour front, said that he had warned about the camp’s unsafe location and vulnerability to ISIS attacks. And they keep coming without apparent regard for risk or cost. “They are brave and they fight without calculation,” said one Kurdish communist fighter who fought alongside Peshmerga at Kudilah, but who is usually with the PKK.

He told us that he often hears Shia songs at the camp. “That’s not a good sign of things to come,” he said, because there would be conflict between Shia and Sunni Arabs who some suspect of giving inside information to ISIS, although the few Shia and Sunni Arab soldiers our research team interviewed from the camp deny this is so. The PKK fighter also reminded us that the Sunni Arabs in Mosul initially supported al Qaeda against the Americans, and welcomed ISIS with open arms as a way of taking power back from the Shia, whose installation in power they still blame on the U.S.

On March 19, ISIS rocket fire killed U.S. Staff Sgt. Louis Cardin and wounded several other Marines from the nearby “Fire Base Bell” while they were at the Iraqi camp. This was only the second death of a U.S. soldier since the withdrawal of American troops from Iraq in 2011.

The Pentagon immediately announced that more troops would be sent to the sector to support “Operation Inherent Resolve,” of which the Battle of Kudilah formed a part. All in all there are already some 5,000 U.S. soldiers in Iraq, more than the official cap of 3,870.

Fire Base Bell, unacknowledged until Sgt. Cardin’s death, is apparently the first American-manned combat post in Iraq since 2011. Its task is to provide “force protection” for the 15th Division. The presence of 155mm M777 howitzers at Bell give the couple of hundred Marines there offensive capability, suggesting a larger combat role for American forces than the U.S. government has admitted.

At dawn on March 24, the Iraqi army’s 15th Division successfully launched an offensive to clear Kudilah and some of the surrounding ISIS-held villages in what Iraq’s Prime Minister Haider al-Abadi described as the first phase of the campaign to liberate Mosul. Assisting was the U.S. Air Force, many of the same Arab Sunni tribesmen previously involved at Kudilah, and Marines from Bell who provided covering fire. Peshmerga remained in the rear as backup, unhappy about the slow pace of the Iraqi army’s advance.

Sunni Arab tribesmen have fought bravely since their first setback at Kudilah, and many have been wounded or killed, including one of the sheikhs who led the original assault on Kudilah. But they cannot advance without massive assistance from Iraqi Army regulars, and at the same time they fear that the Iraqi Army won’t give their fellow tribesmen, who may be living under ISIS rule reluctantly, a fair chance to evacuate.

The apparent lesson from the previous month’s Battle of Kudilah was the need for overwhelming force to dislodge ISIS. But the deeper problems remain: how to maintain cooperation among coalition forces in the long run, and what is to be done in the future to hold together Iraq, resolve its profound sectarian divisions, and prevent the interference and incitement of larger regional and geopolitical forces.

“The local Daesh fighters may be brave or cowardly, mostly cowardly; but the foreign fighters are fierce,” said Rashid, a young Yazidi fighter who used his vacation time from college in the summer of 2014 to train for a week with Kurdish Marxists in Syria (YPG) because he knew that after the fall of Mosul in June 2014, ISIS would soon attack his people at Mount Sinjar. If not for him and a few comrades who opened a small breach in ISIS lines on the day ISIS surrounded Sinjar in early August that year, many thousands of Yazidis might never have escaped the slaughter that did consume thousands of others.

“And then what?” I asked. “What happened once the corridor was secure?” His answer was disarming and hopeful: “I had to go back to school. Archaeology means a lot.”

Kurds and Yazidis are fighting for their survival, or rather, as they say, the survival of “Kurdeity” and “Yazideity.” These are core cultural values, sacred and inalienable, which give a sense of “who I am” and “why we are” in a world of ever shifting sands. And the level of commitment to fight and, if necessary die or sacrifice their families in defense of these values, matches or surpasses that of the Islamic State fighters (and al Qaeda’s al Nusra fighters) that we have interviewed and tested with a variety of psychological measurements on “will to fight.”

But neither the Kurds nor the Yazidis want to venture beyond their homeland to take on the Islamic State, unless as junior partners in a coalition with Sunni Arab tribes led by America, France and other European allies.

And here’s the rub. The Sunni Arab tribes of Iraq for the most part enthusiastically welcomed the arrival of ISIS, which they call “The Revolution” (Al-Thawra), as a way to recover their political dominance and exact revenge for their social and economic degradation by Iraq’s Shia-led government that (according to the Sunni Arabs we interviewed) America imposed and Iran now owns.

Relations soon soured, especially among the tribal sheikhs and other elites when ISIS leaders and local supporters began to seize their power and wealth. Relations deteriorated rapidly when ISIS’s initial offers of amnesty and forgiveness proved to be a ruse to facilitate entrenchment in the local population, and gave way (usually after 10 days or so) to gruesome summary executions of anyone opposing them, anyone connected with the government military or police, any adult Shia (some children might still be made into Sunni), or anyone protecting those condemned.

Even if a coalition involving Sunni Arab forces succeeds in dislodging ISIS from Sunni Arab territory, and even if—a very big if—a bloody settling of accounts between Sunni Arab and Shia and between pro-ISIS and anti-ISIS Sunni tribal factions can somehow be avoided, the conditions that led to ISIS’s emergence among the Sunni Arabs of Iraq (and Syria) have hardly changed and arguably worsened.

And although the Kurds and Yazidis want America, France and other Europeans on the ground, at least for now, the Sunni Arabs don’t. Faced with a choice between continued ISIS rule versus repeat obeisance to an American-led coalition or Shia rule or both, most Sunni Arabs in the region might still opt for ISIS or worse, as many previously did for al Qaeda.

What does “America” mean on this Iraqi battlefield? Our interviews and testing of the various participants in the fight for Kudilah revealed different perceptions about the physical and spiritual force of the United States versus the Islamic State.

ISIS and Kurdish fighters both tend to rate America’s physical force at the maximum on both fixed and continuous measurement scales, but they rate America’s spiritual force as middling. By contrast, both ISIS and Kurdish fighters rate ISIS’s physical force as meager or middling, but it’s spiritual strength at the maximum. Most fighters on all sides think that material prowess and interest drive the U.S., whereas spiritual belief and commitment drive ISIS

Both ISIS and the Kurds also tend to rate the Peshmerga’s spiritual force as greater than the Peshmerga’s physical force, while they rate the Iraqi Army’s spiritual force to be significantly less than its physical force (except for Kurdish members of the Iraqi Army, who tend to rate Kurdish units of the Iraqi Army the way ISIS and other Kurds rate the Peshmerga). ISIS and Kurdish ratings of the PKK and YPG are closest to ratings of ISIS; these three forces are viewed as the most spiritually driven of all.

In other tests, we find that the more the people believe in the enemy’s spiritual force the less they are inclined to make costly material sacrifices against the enemy. The Islamic State’s perceived spiritual force seems to intimidate, even paralyze some of its adversaries.

For Kurds on the front line, their tendency to perceive their own spiritual force to be on a par with the Islamic State translates into expressed as well as actual unwillingness to make costly sacrifices in the fight against ISIS, unless they perceive ISIS to threaten directly their sacred value of “Kurdeity.” Perceptions of lack of spiritual and physical prowess with regard to Sunni Arabs fighting ISIS (whether as Iraqi Army or as militia) is associated with perceived lack of willingness to fight to the death, and especially if the fight is seen as an attempt to preserve Iraq rather than recover traditional lands. As one Sunni Arab colonel told us as fighting raged: “I fight zero percent for Iraq and 100 percent for our Sunni land.”

These findings give sense to the actual course of fighting and the final outcome at Kudilah—an outcome that is arguably as relevant to the effort to retake Mosul and degrade the Islamic State as coalition planners thought it might be, but in a very different way than imagined.

One Kurd, a master sergeant named Hamid, who fought alongside Americans in Fallujah, Ramadi, and a dozen other places and was wounded three times, said after Kudilah: “Our men, even our generals, are subject to Americans who come here. Without the Americans and French [air forces] we wouldn’t be able to hold the line even if we were all willing to die for Kurdistan, which I’m ready to do and sacrifice my family for. The [local] Daesh fighters may not be so willing to die, if not for the foreign fighters who command and spirit them, for they are the bravest, fiercest and most vicious of all. I hope America and France have the heart to stay with us.”

Weighing the relative power of ideas versus mere means has been debated in philosophy as well as in politics and military strategy since the dawn of recorded history. As Sun Tzu remarked in The Art of War more than 2,500 years ago: “The Moral Law causes the people to be… undismayed by any danger.”

Former Marine General Doug Stone (who grew up on a Navajo reservation, which he says prepped him to consider cultural preferences and the power of ideas as decisive, even in battle) asked Hamid: “OK, they’re brave because they believe in their ideas, and that can make a huge difference in battle, and can win wars even after battles are lost. But what do you think Daesh would do if we [Americans] came back here with soldiers and tanks?”

Hamid’s response: “They would not turn away, but would rush forward and die.” To which Stone retorted: “Now that’s my kind of enemy, but I don’t think they’re that stupid.”

One might say, “So what if ISIS fighters are undismayed by danger and willing to rush forward and die, as long as the other side has more and better-armed divisions and is willing to stay the course.” But nothing in this region’s reality is that simple.

Our fieldwork and studies strongly suggest that the Islamic State believes itself and, where its leaders and foreign fighters are concerned, is perceived by its enemies to be driven more by spiritual values than by material interests and means.

Yet ISIS also believes in military might: that the more divisions it has, the quicker God’s will is done. ISIS also believes that its fighters’ spiritual force allows them to do more with less, which is a critical factor in asymmetric warfare.

Thus, even the inghamasi do not witlessly race towards death; rather, they are often trained to weave through battle lines and survive until they reach the enemy and a specific target. They are the most feared and effective weapons ISIS has. This costly display of determination inspires others to fight on and imparts enduring significance to the sacrifice.

Granted, overwhelming military can probably destroy ISIS leadership, organization and the current crop of foot soldiers. But what becomes of the ever more fragmented Sunni world (which, unlike Shiism, has no generally acknowledged structure of worldly authority)? What could replace the spirit and passion that attracts young men from France, Belgium, Britain, Spain, and a hundred other countries to willingly martyr themselves?

And what of the increasing numbers of young women who, unlike most young women in liberal democratic societies, reject the gains of feminism and multiculturalism, wanting to be clearly distinguished as Muslim women—with unambiguous red lines of what is allowed or taboo, right or wrong.

Massive force alone likely won’t forestall, but may well foster, a reconfiguration of the same elements into a volcanic resurgence of rebels with a cause, even readier for Doomsday.

Unless we comprehend the devotion unto death among many of the ISIS fighters at Kudilah, like the willingness to die of many of the Paris attackers, we cannot fathom how and why ISIS is also able to expand among myriad rebel groups throughout northern Africa, deepen roots in Central and Southeast Asia, and capture the hearts and minds of countless other European residents who, rightly or wrongly, feel that liberal democracy does not care for them and hurts others with whom they identify.

ISIS advances into troubled regions across the planet’s central latitudes because it not only promises revolutionary change but delivers: overthrowing the political and economic order in accord with a radically different moral code for the conduct of society.

In the absence of a devout alternative of passion and significance, many who join ISIS seem to say: “Better an end to the suffering of the status quo, with hope for something better, whatever suffering and horror it takes.”

That, of course, is the heart of the apocalyptic mindset: to save this world it may be necessary to destroy it, and postpone hope to the next life. It is an ultimate expression of the power of seemingly preposterous ideas made real: that privilege of absurdity to which no creature but the human is subject.

Also contributing to this field report from ARTIS Research were Rich Davis, former director of terrorism prevention at the White House Homeland Security Council; Lydia Wilson, Middle East historian and co-founder of the Cambridge Literary Review; Hoshang Waziri, Kurdish political analyst and award-winning Arab playwright; and Doug Stone, former deputy commander of Multinational Forces in Iraq who was tasked with dealing with the aftermath of the Abu Ghraib scandal and gaining trust from Sunni Arab tribes in the 2007 surge against al Qaeda.