IN LATE 1986, a thirty-four-year-old declared doctrinal war on the U.S. Army. With the stroke of a pen, one anonymous major set in motion a bureaucratic insurrection that, decades later, would subsume a cabal of battle-hardened revolutionaries and reshape American warfare. It was the opening salvo, the beginning of a story that ends with a maverick warrior-scholar running Donald Trump’s ramshackle National Security Council.

That winter, Parameters featured an article under the byline Gen. John R. Galvin. But Galvin was not the true author; he had delegated the writing to his assistant, an imperious major putting the finishing touches on his Princeton PhD. David H. Petraeus relished the task.

Warfare is “no longer fought simply by the military,” he wrote. “It now encompasses entire populations . . . and its outcome depends more and more on their collective will, what Clausewitz termed ‘the popular passions.’” Petraeus pilloried the Army for its parochial obsession with firepower and conventional combat. He was warning of chinks in the armor. Unlike the brass, he did not see insurgency, terrorism and guerrilla warfare—“small wars”—as aberrations. Scholarship and a penchant for disruption fueled his diatribe. Petraeus dismissed the efficacy of merely killing rebels and touted the strategic logic of addressing “contentious, long-ignored, but popular issues tied to key facets of national life.” At bottom, war is a human endeavor.

His self-described “ramble” called into question the Army’s capacity to adapt. Military leaders “don’t look up very often,” he observed, so distracted are they by the day-to-day slog. Petraeus worried that the dearth of critical thinking would exact a heavy toll. “Let us get our young leaders away from the grindstone now and then, and encourage them to reflect on developments outside the fortress-cloister,” he concluded. “Only then will they develop into leaders capable of adapting to the changed environment of warfare and able to fashion a new paradigm that addresses all the dimensions of the conflicts that may lie ahead.”

Today, his critique rings prophetic. America’s post-9/11 invasions of Afghanistan and Iraq restored “insurgency” to national-security parlance. The ensuing conflicts were messy and slow. They laid bare the limits of the military instrument and the bankruptcy of conventional doctrine. Vicious, resilient insurgencies unleashed by the Taliban, Iran-backed Shia militias, Al Qaeda in Iraq and, later, the Islamic State have imprinted haunting images on the American psyche.

Trump rode those very waves of fear and angst into the White House. The public’s hunger for closure pales in comparison with its thirst for blood. Over and over again, Trump bewitched voters with promises of consigning ISIS to the fires of hell, without repeating the mistakes of the Iraq War. But evicting insurgents from their strongholds will not suffice. The president cares deeply about optics; he can’t afford for the next ISIS to take root on his watch. Remember when candidate Trump accused Barack Obama and Hillary Clinton of cofounding ISIS? The attack ads would write themselves. Only an enduring victory will do.

IF ANYONE can help the president realize that objective, it’s his national security advisor, Lt. Gen. H. R. McMaster. McMaster first came to prominence in 1997, when he turned his PhD dissertation into a book. In Dereliction of Duty, he excoriates the joint chiefs of the Vietnam War era for not expressing dissent with enough conviction. McMaster always aspired to speak truth to power. The Iraq War turned principle into deed.

It was during the Iraq War that the chain reaction triggered by Petraeus’s ghostwriting reached a climax. Along with James N. Mattis—now Trump’s defense secretary—a cast of erudite field officers and a clutch of civilian intellectuals, McMaster and Petraeus reengineered the way the United States thinks about warfare. They revolutionized a U.S. military culturally predisposed to the status quo. They changed the government’s most obstinate bureaucracy from within. They proved that America’s storied warfighters, peerless though they are in dispatching conventional foes, are alone no match for the insurgencies that have metastasized throughout the Middle East. McMaster, Petraeus and their fellow rabble-rousers were dubbed “COINdinistas,” a tribute to the figurative insurgency they launched in order to teach the U.S. government how to fight literal insurgencies.

The Iraq War was their crucible. It crystallized for them that defeating insurgents rests on a symbiosis between soldier and civilian, between killing and rebuilding. In February, 121 retired flag officers, Petraeus among them, reaffirmed that precise belief in a letter to Congress. They averred their “strong conviction that elevating and strengthening diplomacy and development alongside defense are critical to keeping America safe.” They turned Mattis’s own words against him. As the head of Central Command, he once said, “If you don’t fully fund the State Department, then I need to buy more ammunition.” Historically, that’s a bipartisan sentiment, verging on gospel.

So when the White House announced in mid-March that it aimed to enfeeble the State Department and USAID, and extinguish the United States Institute of Peace, it’s no surprise that national-security pundits across the political spectrum struggled to suppress the invective bubbling beneath the surface. Some tempered their rage to inveigh against the president’s “skinny budget.” Many are summoning the ethos of liberal internationalism. The more compelling rejoinders, though, are speaking to the countless ways in which Trump’s budget would damage America’s cold, hard material interests. Because it would. It would jeopardize what every elected official claims to treasure without reservation: America’s shimmering coffers and legendary warfighters. The sheer symbolism of Trump’s proposal, regardless of its plausibility on Capitol Hill, speaks volumes. Its shockwaves will reverberate and linger.

The White House’s budget outline marks the apex of a string of contradictions. The president’s relationship with the military is perplexing. Retired four-stars head his Homeland Security and Defense Departments, and an active-duty three-star sits atop his NSC. Trump likes being seen in the company of generals, though some suspect he’s using them as props. His ostensible deference didn’t stop him from publicly blaming them for the botched Yemen raid and subsequent death of a Navy SEAL. In the greater Middle East, Trump has empowered his commanders, but hasn’t provided a semblance of strategic vision—what’s the endgame?

The administration’s disconnect between military action and political outcome is palpable. Officers in the field have been authorized to call in air strikes without permission from more senior officials. On April 13, Gen. John W. Nicholson Jr. dropped the “mother of all bombs” on an ISIS tunnel complex in remote eastern Afghanistan. It was the most powerful non-nuclear weapon ever used in combat and, reportedly, employed without White House signoff. But it’s not just Trump who’s guilty of confusing tantalizing explosions with sound foreign policy. Cable news worked itself into a frenzy, obscuring the difference between tactics and strategy, one awestruck chyron after another. Few paused to ask: what’s stopping another hundred ISIS fighters from replacing those killed?

“We have to start winning wars again,” the president exhorted on February 27. Days later, he pledged to “give our military the tools you need to prevent war and, if required, to fight war and only do one thing. You know what that is? Win. Win! We’re gonna start winning again.” The irony is tragic and comedic, in equal measure. A few weeks later, Trump proposed a budget that would deprive the military of the exact tools he promised them. He seeks to cripple the civilian agencies that consolidate combat success into political victory. Military power divorced from diplomacy cannot win conventional wars. In small wars, raw firepower is even less decisive.

If Trump were to succeed in budgetarily castrating the civilian agents of U.S. foreign policy, he would harm national security. In Iraq, where the administration has escalated the fight against ISIS, he would render the efforts of servicemen and women less consequential, their triumphs fleeting. Mosul will fall. What happens the day after? Sunni and Shia, Arab and Kurd, are unlikely to find peace overnight. Killing bad guys does not a foreign policy make. Without a concerted strategy of security, diplomacy and development, popular passions will once again engulf Iraq. Déjà vu of the worst kind—the kind that sucks American soldiers and dollars right back in.

No White House official is more keenly attuned to this dystopian fate than McMaster. No national-security professional exerts more influence in the new administration. “H. R. knows firsthand the value of diplomacy in bringing conflict to a conclusion favorable to the United States, at the minimum possible cost in lives and dollars,” retired Lt. Col. John Nagl told me. “H. R. knows that in his bones.” Nagl is no ordinary combat veteran. A COINdinista of the highest repute, he possesses unique insight into McMaster and is unencumbered by chain of command. “It must gnaw at his innards,” Nagl said of his friend, “that the administration he is serving is attempting to do this kind of damage to institutions that are so important to the security of our great nation.” He was uninterested in mincing words: “These ideas are asinine.”

And that’s the most confounding paradox of them all: that H. R. McMaster could possibly acquiesce to something so flagrantly antithetical to the American way of war he fought so hard to transform. He knows that “small wars” is a misnomer. When a president fantasizes about short, winnable wars with military-only solutions, young men and women pay for that mistake with their lives, and taxpayers with their wallets. It beggars belief that the strategist of a generation could be complicit in a national-security policy unmoored from common sense.

TWELVE YEARS after decimating an entire Republican Guard tank formation without loss, Herbert Raymond McMaster returned to Iraq. It didn’t take him long to discover that the pitched battles he and John Nagl waged against Saddam Hussein in 1991 had gone the way of the musket. This was a different sort of war.

As the director of Central Command’s advisory group in 2003, McMaster visited every brigade in Iraq. When he came across the 101st Airborne Division in Mosul, he was pleasantly surprised to find Maj. Gen. Petraeus experimenting with counterinsurgency. The two hadn’t spoken in a while. Six years earlier, Fred Kaplan recounts in The Insurgents, McMaster’s intellectual honesty caught Petraeus’s eye. Both officers had written their PhD dissertations on the Vietnam War. Petraeus chose not to publish his for fear of insulting the commanders who held sway over his career; McMaster did not share that compunction. Dereliction of Duty bears the subtitle “Lyndon Johnson, Robert McNamara, the Joint Chiefs of Staff, and the Lies That Led to Vietnam.” Not exactly subtle. Petraeus was an aide to the chairman of the joint chiefs at the time. He called McMaster and instructed him to reach out directly should he ever come under fire for what he’d written. The need never arose, but after reconnecting in Mosul, they stayed in touch. McMaster would experience his own watershed soon enough.

It was the spring of 2005, and Tal Afar was in shambles. Colonel McMaster arrived at the helm of the Third Armored Cavalry Regiment to find the city, thirty-five miles from the Syrian border, beset with sectarian violence. Iraqi and foreign-fighter jihadists, along with elements of the local Sunni population, ran riot. Al Qaeda in Iraq, ISIS’s forebear, targeted the minority Shia with heinous violence, the kind of theatrical brutality all too familiar today. A Shia police force fanned the flames with indiscriminate reprisal killings. In Insurgency and Counter-Insurgency in Iraq, Ahmed S. Hashim recalls that “Tal Afar looked like one of those forlorn humanoid settlements on a distant and barren planet in the outer reaches of the solar system.” On multiple occasions, the U.S. military ousted the insurgents. But each time they came back. The city became an insurgent sanctuary, a convenient support base for launching attacks on Mosul, which markedly deteriorated after Petraeus’s departure.

In the April 10, 2006 issue of the New Yorker, George Packer painted a vivid picture of McMaster’s pioneering operations in Tal Afar. On his own initiative, McMaster employed classic counterinsurgency tactics in a bid to “clear, hold, build.” (Among the books McMaster assigned his regiment before deploying was Learning to Eat Soup with a Knife, by John Nagl. Combatting insurgency is “messy and slow, like eating soup with a knife,” T. E. Lawrence wrote in Seven Pillars of Wisdom.) Clearing and holding went well enough. He collaborated with the Eighty-Second Airborne and special-operations units to dispossess the jihadists of their strongholds. He ordered his soldiers to establish neighborhood outposts and to dismount their armored vehicles while on patrol (shifting the emphasis from protecting themselves to protecting civilians); to curtail gratuitous night raids (which embitter and alienate); to use minimum necessary force when possible (to avoid collateral damage); and to treat the locals with a dose of dignity and compassion. “Every time you treat an Iraqi disrespectfully, you are working for the enemy,” he instructed. Trust yields intelligence, and intelligence saves lives. James Mattis, McMaster’s current counterpart at the Pentagon, adopted a similar philosophy as commander of the First Marine Division in Anbar Province during the early years of the war. Tom Ricks documented Mattis’s “first, do no harm” approach in Fiasco, a 2007 Pulitzer finalist.

Building was another challenge entirely. McMaster worked to restore basic services, stood up a local security force and encouraged municipal workers to return by paying their wages. He rather shrewdly funneled reconstruction funds through tribal sheikhs. Appearances matter; people were more likely to welcome the return of order and infrastructure if they could plausibly deny affiliation with the American occupiers. Sowing trust among the locals proved most daunting. “When we came to Iraq, we didn’t understand the complexity—what it meant for a society to live under a brutal dictatorship, with ethnic and sectarian divisions,” McMaster told Packer. The Jordanian terrorist Abu Musab al-Zarqawi understood the complexity. Under his leadership, Al Qaeda in Iraq had brought Tal Afar to the brink of civil war. Zarqawi’s brand of terror was calculated and effective. McMaster knew that if he couldn’t find a way to end the cycle of revenge killings, his regiment’s progress would evaporate. Taking death squads off the street was but a Band-Aid.

And then the rubber met the road. As Packer observed, “Shiite sheikhs accused the Sunnis of tolerating the presence of terrorists, and Sunni sheikhs accused the Shia of making unwarranted generalizations about them.” McMaster tasked an exceptionally competent squadron commander with reversing Zarqawi’s damage, through diplomacy at the community level. Lt. Col. Chris Hickey had to become an expert in tribal politics overnight—in his words, “to switch the argument from Sunni versus Shia, which was what the terrorists were trying to make the argument, to Iraqi versus takfirin.”

This mismatch is representative of so many failures throughout the occupation. A soldier was forced to play a role better suited to an anthropologist. In The Mission, Dana Priest illustrates how, by the turn of the century, the United States had become over-reliant on its military to carry out a broadening set of objectives, at the cost of the State Department and its “shriveling” resources. In 2006, Praeger reissued David Galula’s 1964 book Counterinsurgency Warfare, with a new foreword by John Nagl. The French counterinsurgent argues that the responsibilities of the soldier, the policeman and the civil servant are drawn into a state of mutual dependence by COIN’s inherently political character.

The position McMaster put Hickey in wasn’t uncommon. Before he was a COINdinista, Peter Mansoor led the First Brigade, First Armored Division. “I was a brigade commander on the ground in 2003–4 and almost never saw a representative of the Coalition Provisional Authority. We desperately needed civilian expertise to help us with reconstruction and to reform the local governments,” the retired colonel told me. “There are certain aspects of counterinsurgency that really only civilians can provide.”

Nagl had a similar experience. “I became a Sunni-Shia religious, cultural and political expert—‘expert’ in quote marks!—on the fly because there was nobody else to do it,” he lamented. “When I was on the ground in Iraq trying to untangle tribal politics, I was despondent that I didn’t have help from the State Department, USAID or anybody. And I became convinced that investment in diplomats would literally have saved my soldiers’ lives.”

Even more comprehensively than Petraeus in Mosul, McMaster supplanted chaos with stability in Tal Afar. His accomplishments were hailed as a wild success. And rightfully so. His was the first systematic counterinsurgency operation of the Iraq War—conducted, as Kaplan points out, “with total independence from headquarters”—at a time when the mere utterance of the “i-word” invited opprobrium. But Tal Afar was one city, and McMaster one man. The insurgents cleared from one town would simply move to another, creating a “balloon-squeezing phenomenon” that prevented security from improving country-wide. It’s what Galula called an “accidental mosaic.” Furthermore, the very nature of military deployments precludes the kind of continuity that might have seen McMaster achieve more in Tal Afar. He got his orders and moved on. On February 22, 2006, Al Qaeda in Iraq blew up the Al-Askari Shia shrine in Samarra. The jihadists got the civil war they wanted.

Back in Washington, the war of ideas Petraeus sparked in 1986 was coming to a head. After years of surreptitious politicking, chain-of-command bending and painstaking intellectual salesmanship, Petraeus and McMaster were finally making inroads. In September 2006, Petreaus installed McMaster and Mansoor into a secret advisory group the joint chiefs had assembled to rethink Iraq. The “council of colonels” was afforded the opportunity to dispense with ceremony and tell the most senior officers in America’s military the hard truths they couldn’t countenance: Iraq was roiled in an insurgency. Clean victory and hasty withdrawal were pipedreams. Killing the enemy would not be enough. Only an injection of new commanders, resources and doctrine could salvage the crisis. Meanwhile, a network of influential experts, scrupulously cultivated by Petraeus, was working to convince President Bush to sign off.

They were on the cusp. Petraeus and his cadre of doctrinal disobedients put pen to paper. On December 15, 2006, they published FM 3-24, the COINdinistas’ true statement of purpose. The paradigm-shifting counterinsurgency field manual, which cites McMaster’s exploits in Tal Afar and Mattis’s in Anbar Province, turned the American way of war upside down. It codified hearts-and-minds COIN. Corporals and lieutenants would have to unlearn much of what the military had taught them. An insurgency’s center of gravity is the civilian population. The public is the prize; win them over and the insurgents lose support. FM 3-24 made its authors look more like agents of change than petulant insubordinates. They had broken free of the fortress-cloister.

Bush finally acceded: America wasn’t going to kill its way out of this morass. A month after the field manual’s release, the president pinned a fourth star to Petraeus’s shoulder, gave him charge of all U.S. forces in Iraq and green-lit the surge. Petraeus named Mansoor his executive officer and tapped McMaster to lead his strategic-assessment team. The COINdinistas were insurgents no longer.

THE SURGE’S abiding relevance lies not in the operational realm but in the conceptual. It drew military and nonmilitary personnel into a state of mutual dependence, made protecting Iraqi civilians a central mandate and confronted the conflict’s political accelerants. Killing insurgents was subordinated to a new directive: making sure their ilk couldn’t return.

“We had a lot of military power on the ground to fight the insurgency,” Mansoor told me. “What we lacked was a robust, complimentary civilian effort to solidify the gains that the soldiers and marines were making on the streets of Iraqi cities and towns.” So General Petraeus and Ryan Crocker, the new ambassador in Baghdad, embedded provincial reconstruction teams (PRT) in combat units, filling their ranks with staff from USAID and the Departments of State, Agriculture and Justice. PRTs deployed to the front lines to tackle the socioeconomic drivers of the conflict. Soldiers and civilians put themselves at risk to secure and rebuild communities.

The surge gave warring factions breathing space, a narrow window for political accommodation. Stop shooting, start talking. But security provision alone couldn’t bring them to the table. In The Counterinsurgent’s Constitution, Ganesh Sitaraman argues that in small wars, the counterinsurgent must initiate reconstruction in the midst of the conflict. “Counterinsurgency embraces a bottom-up approach,” he writes, “that grows organically from the local conditions and context: the population’s capacities and needs, their traditions and preferences. Organic reconstruction reframes warfighting as village-building.” Sitaraman sees reconciliation programs as “weapons of war, instruments of lawfare that can be designed to reduce or even eliminate the insurgency.” At the height of the surge, an Army combat brigade and a civilian organization that Donald Trump now wants to defund put that theory to the test. Together, they weaponized reconciliation in the “Triangle of Death.”

Mahmudiya District, Baghdad’s ethnically mixed southern doorstep, earned its bleak moniker during the early years of the war. Assassinations, public beheadings, improvised explosive devices and armed banditry punctuated virulent sectarian warfare. “Not one man in a hundred will stand up to a real killer,” James Mattis once remarked to the author Bing West. “It’s ruthlessness that cows people.”

Col. Michael M. Kershaw was told a year ahead of time, far longer than usual, that his brigade would deploy to Mahmudiya. Early on in his preparation, he realized that “this was fundamentally a problem of counterinsurgency.” But it was not, contrary to the assumption I voiced to him during our interview, McMaster’s operations in Tal Afar that brought him to this conclusion. He wasn’t terribly chagrined at my mistake.

Kershaw and McMaster, it turns out, go way back. They were in the same West Point class, where they played rugby together and shared a course on revolutionary warfare. They were both company commanders in Iraq during the Gulf War. When Kershaw attempted to dabble in counterinsurgency in Afghanistan in 2003, McMaster noticed. Kershaw was leading the First Ranger Battalion in Kunar Province and discovered “the futility of trying to pick these guys off.” McMaster flew in and received a briefing from Kershaw’s second-in-command. When McMaster took COIN a few steps further in Tal Afar two years later, Kershaw was tracking his progress.

Kershaw and the Second Brigade of the Tenth Mountain Division arrived in Mahmudiya in August 2006. From the beginning, he said, he was determined to “harness something that would outlast our tour of duty.” The Triangle of Death’s new counterinsurgents manned neighborhood outposts, with an eye toward restoring community security. Special operators killed and captured Al Qaeda and its foreign fighters. Kershaw’s deputy, Lt. Col. John Laganelli, told me he worked to bring agricultural and economic-development capabilities into the region, “to create some form of normalcy for the people.” Meanwhile, the “Awakening” had moved from Anbar Province and was sweeping across Mahmudiya. Local Sunnis began betraying Al Qaeda, electing to supply the U.S. military with intelligence in exchange for pay and promises of safety.

In Kershaw’s telling, plenty of tribal leaders wanted to talk, but the Second Brigade was struggling to consolidate the ink dots of “awakened” locals into a big-picture compromise. There were too many moving pieces, too little trust: “We were trying to navigate an archipelago of societal islands. The campaign was like an island-hopping exercise.” And Kershaw was, by all accounts, the Army’s resident authority on south Baghdad. “I was the Mahmudiya expert,” he said matter-of-factly. “But man, I went to public school in east Texas. I could only scrape the surface. The language barrier. The culture barrier.” Someone in Kershaw’s orbit coined the term “sheikhapalooza” to denote the unproductive theatrics that characterized the military’s sit-downs with tribal leaders.

By the summer of 2007, the Second Brigade had expelled Al Qaeda and bloodied the remaining insurgent groups. A promising, yet tenuous, calm took hold. Fearing regression, Kershaw’s embedded PRT connected him with the United States Institute of Peace, a congressionally funded peacebuilding outfit—which the colonel “knew nothing about,” he’s still embarrassed to say. When he met with USIP staff in the Green Zone, “a lightbulb went off,” he told me. “Their set of capabilities was something we could not get elsewhere. They had Iraqis who could actually run the negotiations between the sheikhs. They could seat Iraqis with Iraqis.”

USIP’s objective, in its view, was to preempt revenge. Orchestrate a reconciliation process capable of suturing the ethnosectarian wounds the jihadists had wrought. Kershaw saw USIP in a utilitarian light: just as he turned to special-operations units to kill and capture irreconcilables, he turned to USIP to reconcile the rest. “Those were desperate times. We were looking for anyone with value added.” Desperate they were. There were almost 2,200 IED incidents during the Second Brigade’s fifteen-month tour. Fifty-four soldiers were killed in action. Kershaw was eager to maximize the returns on his soldiers’ costly investment. He didn’t need FM 3-24 or media-savvy Petraeus to teach him about civil-military innovation. But the new field manual and Petraeus’s public championing of counterinsurgency, Kershaw told me, did give his brigade the cover it needed to engage deeply with the people of his sector and keep Al Qaeda on the ropes. (McMaster actually came down to Mahmudiya during Kershaw’s deployment to visit his old friend and exchange ideas.)

USIP tapped into its reservoir of Iraqi intermediaries, whom the institute had for years been working with and training in conflict management. They worked closely with the Second Brigade to map out Mahmudiya’s intricate fault lines and volatile power centers. Which individuals and which clans were best positioned to convince their tribes to negotiate with bitter enemies? Kershaw’s soldiers went to great lengths to protect and shuttle USIP personnel—one such escort was struck by an IED. Sarhang Hamasaeed, USIP’s current director of Middle East programs, went out of his way to emphasize the complementary dynamic between the institute and the military. USIP wasn’t exactly in a position to rid Mahmudiya of Al Qaeda, he told me, but neither was the Army equipped to rebuild social cohesion.

USIP marshalled its acute expertise and capitalized on its ambiguous provenance. Despite having “United States” in its name, the institute was able to disassociate itself from the oft-reviled occupation (in Kershaw’s opinion, USIP’s Iraqi-led approach allowed it to function like “an NGO we fund as a front”). All the while, it was leveraging its pedigree in diverse corridors of power. Kershaw was constrained by chain of command; USIP was not. The institute collaborated with the State and Defense Departments to secure buy-in from integral power brokers at the municipal, provincial and national levels. Despite a hostile reception, USIP was able to extract an endorsement from officials in Prime Minister Nouri al-Maliki’s inner circle.

USIP meticulously cultivated a web of local mediators and Triangle of Death stakeholders. The resulting delegation possessed unparalleled insight into the competing interests and hidden motives of the aggrieved parties. USIP and its delegation turned their attention to Mahmudiya’s exiled Sunni leaders. Without them, the entire enterprise would grind to a halt. Post-Saddam Iraq had devastated their livelihoods and forced them to take refuge in Amman, Jordan. They held America responsible. Young firebrands and other radical elements in their tribes vied for influence. Some espoused sectarian warfare. Both Rusty Barber, USIP’s chief of party in Iraq at the time and an architect of the peacebuilding initiative, and Colonel Kershaw described the links between these exiles and Mahmudiya’s insurgents in cryptic terms. At the very least, Barber told me, they “were capable of operating as spoilers to any agreement they were left out of.” They “definitely had blood on their hands,” Kershaw said.

Among the delegates USIP recruited for the Amman mission was Ali al-Mufraji, a thirty-five-year-old general in the Iraqi army. He was the most senior Iraqi military officer in Mahmudiya and, in Kershaw’s experience, “the real power behind the throne,” a reference to the local Shia government. When Sens. Lindsey Graham and John McCain visited the sector, Kershaw suggested that they meet with Mufraji. In Amman, the one-star general’s job was to convince the exiles of the initiative’s viability, especially on security grounds. A Shia married to a Sunni, Mufraji’s pragmatism helped shift the tenor of the talks, which were nearly derailed by suspicion. The most formidable source of agitation was the widespread detention of Sunnis haphazardly branded as terrorist accomplices. Mufraji brandished his laptop, popped open a spreadsheet and revealed the status of tribesmen in custody. His candor and transactional efficiency fostered trust. The exiles accepted the project’s merits and, later, convinced Mahmudiya’s senior tribal leaders to participate in a Hail Mary dialogue. In a letter dated August 23, 2007, Kershaw credited USIP with “creating an atmosphere where real communication could take place” and implored the institute to see the project through.

Months of ground work were to culminate in a conference at Baghdad’s Al-Rashid Hotel. The Army provided organizers and participants with transportation and employed robust measures to protect the hotel itself. Rusty Barber told me that General Petraeus personally redirected funds to the reconciliation process.

The three-day conference began on October 16. USIP crafted the format and agenda. The institute’s Iraqi facilitators conducted the proceedings. They instructed participants in mediation techniques without besmirching their traditions. A few verbal altercations boiled over, but were promptly cooled. By day two, the community leaders had reached consensus on goals and corresponding action items, which USIP channeled into a draft accord overnight. On the third day, pugnacious debate over the final text yielded “Mahmoudiya: Cornerstone for Peace and National Accord,” a concrete framework for the reconstruction of the district. Thirty-one Shia and Sunni tribal leaders, so recently warring, signed the document in view of Iraqi and foreign press. The pact’s symbolic value wasn’t lost on Kershaw. To him, its impact was simple: “It legitimized the ‘Awakening.’” Stop shooting, start talking was officially socially acceptable. Al Qaeda had lost its local base of support.

Violence declined precipitously. The 101st Division’s Third Brigade, which replaced Kershaw’s, lost a single soldier during its deployment. The Army trimmed its presence from a brigade combat team of 3,500 to a battalion of 650. The entire USIP project cost American taxpayers around $1.5 million, roughly the price of a single Tomahawk cruise missile. On February 11, 2009, Petraeus praised “USIP’s on-the-ground peacebuilding efforts” in a letter to the Office of Management and Budget. In it, he singled out the Mahmudiya initiative as “a striking success story.” The pact has endured the Arab Spring and the rise of ISIS. It holds to this day.

THE INTENTION here is not to wax poetic about how the mighty COINdinistas injected thirty thousand troops into Iraq, saved the day and galloped off into the sunset. Petraeus has been mythologized too often. The military historian Douglas Porch, Petraeus’s harshest critic, titled his scathing polemic Counterinsurgency Myths. Even sympathetic observers point to Petraeus’s preoccupation with his own glory and his cunning in spinning self-serving narratives.

Nor is it reasonable to paper over U.S. killing. Brought back to Iraq to oversee strategy during the surge, McMaster was vehement that some insurgents had too much blood on their hands to be politically accommodated. Under Lt. Gen. Stanley McChrystal, Joint Special Operations Command took scores of these irreconcilables, including Abu Musab al-Zarqawi, off the battlefield. But McChrystal opted for the scalpel whenever possible. His kill-and-capture missions were designed to be discriminate. Collateral damage would only breed more terrorists.

Besides, controlling territory is not the jihadist’s only concern. Al Qaeda and ISIS inflict the deepest wounds on the virtual battlefield. A suicide bombing at a market has little military value; it resonates as “propaganda of the deed.” ISIS recruits foreign fighters and radicalizes homegrown terrorists online. Viral, emotive images are its weapons of choice. And as Graeme Wood argues in The Way of the Strangers, ISIS’s weaponization of theology cannot simply be dismissed as a bastardization of Islam.

Mending social cohesion in Iraqi communities, therefore, is only part of the story. Suffice it to say, the combination of the surge and the “Awakening”—the widespread Sunni uprising against Al Qaeda, underway before Petraeus took over—dramatically reduced violence. From 2004 to mid-2007, more than 1,500 civilians died every month in Iraq. By December 2007, that number plummeted to five hundred. From June 2008 to June 2011, around two hundred civilians died every month.

The military could not occupy Iraq forever. America failed to establish a sustainable political order before withdrawing. Communities lacked closure, and tensions gestated. Maliki’s overt hostility toward the Sunnis stoked discord and violence. ISIS exploited these divisions, co-opted Sunni tribes who once fought alongside the Americans and, in short order, routed the Iraqi army. In June 2014, ISIS declared a caliphate over a broad swathe of territory. At its peak, it controlled 40 percent of Iraq.

In Washington, reluctance to intervene understandably found voice. The Iraq War scarred America. Words like “quagmire” are never far from the lips of those who advocate for retrenchment. The Iraq War is as politically corrosive as ever, a reliable dog whistle that incites rabid denunciations of hegemonic overreach and paternalistic democracy promotion. But Iraq is more than just a trope. The decision to invade, among the worst foreign-policy blunders in U.S. history, and the prosecution of the war are two different things. Conflating counterinsurgency with the neoconservative worldview—just because they have Iraq in common—is reductive. Petraeus and McMaster did, in fact, make common cause with neocon stalwarts like Eliot A. Cohen and Frederick W. Kagan as they labored to convince President Bush to change tack. They were playing the hand they were dealt. Neocons broke Iraq; Petraeus and McMaster were tasked with putting it back together. Trump himself seems amenable to this sentiment. In March, he told Haider al-Abadi, Iraq’s moderate prime minister, “We shouldn’t have gone in, but certainly we shouldn’t have left.”

Jettisoning the lessons of the Iraq War for fear of striking a political nerve would be feckless. Gaslighting the COINdinistas would be cataclysmic.

DONALD TRUMP is in an unenviable predicament. He’s got to defeat ISIS and prevent its resurgence, with a footprint small enough to repel allegations of interventionism. The Pentagon wants to retain U.S. forces in Iraq for years after Mosul is recaptured. “I believe it’s in our national interest that we keep Iraqi security forces in a position to keep our mutual enemies on their back foot,” Defense Secretary Mattis told Senate leaders in late March. “I don’t see any reason to pull out again and face the same lesson.”

The White House has since delegated new authorities to the Defense Department to decide how many troops are deployed in the war against ISIS. Two Pentagon officials made clear to me that Operation Inherent Resolve is a conventional military affair. Adrian J. T. Rankine-Galloway, a Pentagon spokesperson, used some version of “supporting role” five times in our brief exchange. I asked about the day after Mosul falls. “The government of Iraq is responsible for governance and security matters within its territory,” the Marine Corps major responded. A second Pentagon official, this one senior, spoke to me on condition of anonymity. “Once ISIS is defeated, you still have sectarian tensions and divisions. That’s where soft power comes into play,” the official said. Gutting civilian agencies, like Trump has proposed, would “hinder the U.S. ability to prevent insurgencies before they happen.” Surely there’s some middle ground between full-tilt counterinsurgency and what Major Rankine-Galloway referred to as “supporting local partners as those forces liberate territory from ISIS control.”

The lessons the COINdinistas took from Iraq in the 2000s extend beyond that time and place. In Waging Insurgent Warfare, Seth G. Jones conducts an empirical study on the 181 insurgencies that took form between World War II and 2015. Insurgency prevention across the board, he demonstrates, hinges on ameliorating local grievances, “particularly ones associated with low per capita income, ethnic polarization, and religious polarization.” Washington isn’t going to “fix” Iraq in one fell swoop. But Trump cannot afford to defund the organizations doing a measure of good. Michael Singh, managing director at the Washington Institute for Near East Policy, was once responsible for George W. Bush’s national-security policy toward the region stretching from Morocco to Iran. “How we defeat ISIS is just as important as whether we do,” he told me. “We need to leave behind conditions in Iraq both for effective local governance and stable regional geopolitics. It will be worth taking our time to get this right.”

If America is going to prolong putting uniformed men and women in harm’s way, dipping deeper and deeper into the war chest, common sense demands that the administration maximize their impact. If America is going to help Iraq break the endless cycle of sectarian violence—undoubtedly, a prerequisite for hindering an embarrassing ISIS comeback—it will have to find a cost-effective, palatable means of translating battlefield triumphs into political progress. What Trump needs is a force multiplier. Regrettably, the White House’s recent budget proposal sentenced to death an indispensable variable in that equation.

Seven years after Mahmudiya, the United States Institute of Peace executed another unlikely scheme, in the northern city of Tikrit.

Tikrit in 2014 was like Tal Afar in 2005, but worse. Ravaged by calculating jihadists, Saddam Hussein’s ancestral hometown collapsed on itself. ISIS has a vested interest in instability; internecine violence is basically insurgent catnip. Camp Speicher had been home to a few thousand Iraqi military cadets before ISIS weeded out 1,700 Shia, slaughtered them and dumped their bodies into mass graves. It released photos and videos to adorn its sickening propaganda. The Speicher victims represented twenty southern tribes, from nine provinces. By the time a hodgepodge of Iraqi Security Forces and Iran-linked militias ejected ISIS from Tikrit in April 2015, the massacre had been seared into Shia memory.

Civil war seemed inevitable. Shia from the south marched north to avenge their sons. The immediate aftermath of ISIS’s expulsion saw a wave of looting and lynching. Had he been asked, McMaster could’ve scripted the conflagration to come, like an omniscient playwright. In Act One, the Shia conflate every Sunni with a pulse with ISIS and its war crimes. The Sunnis are too busy accusing the Shia of making blatant generalizations to offer nuance. In Act Two, revenge killing begets revenge killing. Tikrit’s displaced locals do not return. No Sunni trusts the overwhelmingly Shia security forces, least of all the militias. In Act Three, the Shia militias use disproportionate force to restore order, falling just short of war crimes. In Act Four, ISIS returns to Tikrit and hoists its black flag. This time, more Sunni tribes than before acquiesce. They’ve come to hate Baghdad more than any jihadist.

McMaster the playwright would’ve been within his rights to anticipate such a bitter tragedy. He knows the motifs inside and out. But in the case of Tikrit, he would’ve been wrong.

Tikrit was the first major Sunni city retaken from ISIS. USIP’s intensive monitoring paid dividends; months before the battle concluded, the institute was already reckoning with the brewing storm. USIP mobilized an intervention team with its network of Iraqi facilitators. Well versed in the fine contours of Tikrit’s tattered social fabric, the team convened a series of meetings in Baghdad. Sarhang Hamasaeed, the institute’s Middle East director, helped design the Tikrit initiative. He likens revenge killing to an improvised explosive device. It hides in plain sight and can detonate at any moment, triggering cascading violence. That violence, he told me, becomes “the cleavage that ISIS exploits,” its fundamental sustenance.

The goal of the dialogue was to dispel notions of collective blame, to introduce nuance. But the situation was “way too hot” to immediately bring the Tikriti Sunnis accused of complicity face to face with the southern Shia mourning their children. USIP dubbed these parties the “inner circle.” What the mediators needed was an “outer circle.” Their homework on local power dynamics bore fruit. They identified viable enablers and probable spoilers. They carefully selected an outer circle of tribal leaders who exerted strong influence over the inner circle. Sunni and Shia a heartbeat away from war gathered under one roof. USIP’s Iraqi facilitators ran the show. (“At the end of the day,” Hamasaeed told me, “you want the Iraqis to have the credibility and the know-how to do this on their own.”) Compelling anecdotes challenged dangerous prevailing narratives. Not every Sunni, it turns out, abetted ISIS. They too lost loved ones. Some Sunni tribes put themselves at risk to protect Shia from the jihadists.

USIP brought crucial stakeholders into the fold. Grand Ayatollah Ali al-Sistani, the most revered Shia cleric in the world, sent two representatives. Sistani’s blessing conferred moderation. The office of the prime minister, meanwhile, cleared four hundred Sunni families of ISIS collusion, allowing them to return home. The disputants struck a bargain virtually unprecedented in tribal tradition. According to the Christian Science Monitor, “In front of more than 30 satellite TV channels, Tikriti tribal leaders denounced the Speicher massacre, blamed IS, and vowed to help Iraqi security forces identify and capture individual culprits within their own tribes, and help identify mass graves.” It was more than a rhetorical coup; the prospect of justice was coming into relief. Bereaved Shia families received moral and financial compensation from Baghdad. In exchange, hundreds of thousands of displaced Tikritis were given a right of return. Monitors were dispatched to the area to deter reprisals.

USIP’s plot was not, alas, a miracle cure for all that ails Iraq. Salahuddin Province and Tikrit, its capital, have recently suffered a number of suicide bombings, in part, the result of ISIS feeling the squeeze in Mosul. And the provincial governor seems to have gone rogue. Under a new policy, authorities are forcibly displacing and detaining hundreds of families accused of ISIS ties. Hamasaeed readily acknowledges USIP’s limits. “We can cut into the communal tensions the militias want to exploit,” he told me. “But we cannot end the militias.”

And yet, in Iraq, “it could be worse” has currency. NPR reported that Tikrit has “confounded expectations,” observing the city center “bustling with life.” The Wall Street Journal described a degree of normalcy and saw “no signs that local resentments are going to turn violent.” Tikrit University has reopened, and most of its twenty-three thousand students, including Shia from the south, are back in attendance. Over 90 percent of Tikritis displaced by ISIS have returned home. And Shia forces are not summarily executing Sunnis with power drills, as was the case during the worst years of the Iraq War. USIP’s follow-up work is ongoing. It has implemented Justice and Security Dialogues in Kirkuk, Baghdad, Karbala and Basra, which are intended to build trust between security forces and the locals they serve.

The real test comes down to resilience. When ISIS or the Shia militias spill blood, are there vehicles of redress strong enough to dissuade victims from reacting violently to attacks designed to provoke just that?

Despite the caricature of a tree-hugging think tank that does nothing but write earnest policy reports, USIP has actionable comparative advantages. In Tikrit, USIP advanced core components of McMaster’s Tal Afar agenda, but with less money. The institute runs lean. Its annual budget of $35.3 million wouldn’t register as a rounding error at the Pentagon. The entire Tikrit project cost around $1 million. In contrast, anti-ISIS operations run the military $11.2 million a day.

John Nagl considers USIP a “combat multiplier,” insofar as its specialists “understand cultures and tribal and local politics more deeply and more instinctually than anyone but the very best and rare American soldiers.” And it’s not restricted by limited deployments. Peter Mansoor lauded the institute’s “staying power.” When the Defense and State Departments move on to the next crisis, he said, “USIP stays behind for a longer-term commitment.” Its longevity allows it to accumulate relationships and granular expertise. Moreover, USIP isn’t beholden to the embassy’s chain of command. Its staff can maneuver around the country to places where neither the State Department nor USAID is permitted.

The institute has shed the baggage of the American occupier, and is respected among Iraqis for not having an agenda. Michael Knights is a foremost expert on Iraqi security affairs. Although he’s distinctly military-centric in his analysis—“I’m not a soft-security person,” he told me—he considers USIP “very credible in Iraq.” I spoke to him not long after he delivered Senate testimony on the future of U.S. policy in Iraq. Visibly disillusioned by inefficient foreign-aid delivery, he sees in USIP a potential viable model: “If the U.S. government could throw some resources at some genuine Iraqi-led organizations—even if USIP were the conduit—it could have a big impact.”

USIP also maintains access to the highest levels of the Iraqi government. “When you come to Washington and you see that thing,” Knights said of USIP’s glassy, Lincoln Memorial–facing headquarters, “you know that you’re somewhere powerful. It has prestige, and prestige matters a lot in a place like Iraq.” In the past seven years, the institute has hosted Iraq’s prime ministers on each of their visits to Washington.

By the end of our interview, Nagl was effusive. “USIP prevents wars from happening and ends them sooner, on terms more favorable to the United States. It keeps American soldiers alive,” he annunciated slowly. “USIP understands how wars end.”

“WE’RE DOING very well in Iraq,” President Trump recently extolled. “Our soldiers are fighting, and fighting like never before.” In March, U.S.-led air strikes killed more civilians than in any other month since the anti-ISIS campaign began in 2014. A single March 17 attack reportedly killed as many as two hundred Mosul residents, and the U.S. military “probably had a role.” Razing ancient cities with women and children still inside—not what most would consider “doing very well.” Rubble and cinder play well both in jihadist propaganda and on CNN, but for inverse reasons. Not to worry: the president has assigned Jared Kushner the Iraq portfolio.

Incoherence is a staple of the administration’s foreign-policy messaging. UN Ambassador Nikki Haley, for instance, declared that Washington would not “focus on getting Assad out” ten days before telling Jake Tapper, “There’s not any sort of option where a political solution is going to happen with Assad at the head of the regime.” In the interim, Trump fired fifty-nine Tomahawk cruise missiles at a Syrian air base in retaliation for the regime’s gruesome chemical attack on civilians.

U.S. policy in Iraq is equally discordant. “As a coalition, we are not in the business of nation-building or reconstruction,” Secretary of State Rex Tillerson recently said. “We must ensure that our respective nations’ precious and limited resources are devoted to preventing the resurgence of ISIS and equipping the war-torn communities to take the lead in rebuilding their institutions and returning to stability.” Empowering Iraqis to take the lead is fine and good. But passing the buck on reconstruction is a sure-fire way to guarantee an ISIS resurgence. “A short-term approach to long-term problems,” Colonel McMaster wrote of America’s post-9/11 wars in 2008, “generated multiple short-term plans that often confused activity with progress.”

The president’s bomb-only approach belies echoes of Sisyphus. Trump may inadvertently sentence America to a lifetime of boulder pushing. Higher and higher the military rolls the insurgent boulder up the hill. Just when the summit is in sight, the boulder falls to the bottom. And so on, for eternity.

A few glimmers of hope, however, may be squeezing through the cracks. Weeks into his presidency, Trump replaced his ethically challenged national security advisor, Michael J. Flynn, with a man once responsible for rooting out corruption in Afghanistan. McMaster now appears to be wresting control of the National Security Council from the White House’s toxic ideologues. Steve Bannon’s permanent seat on the Principals Committee has been revoked, while the director of national intelligence and the chairman of the joint chiefs have had theirs restored. McMaster has relocated Flynn’s deputy, K. T. McFarland, to Singapore. He’s poached Dina Powell, one of the few Trump aides with government experience. Most encouraging, he’s hired a scholar named Nadia Schadlow. Both John Nagl and Peter Mansoor sang her praises, independently and unprompted. Schadlow’s new study hit the bookshelves right around the time Trump was releasing his draconian budget blueprint. The subtitle of War and the Art of Governance is alone cause for cautious optimism: “Consolidating Combat Success into Political Victory.”

It would be a mistake of epic proportions to purge counterinsurgency’s underlying principles for fear of conjuring images of failed nation building. Yes, a full-blown counterinsurgency do-over is as unviable as it is imprudent. But throwing out the baby with the bathwater would be folly. USIP is but one example of diplomatic effort complementing military sacrifice. Good policy need not be bad politics. At bare minimum, Trump has an obligation to uphold his campaign promises to protect core U.S. interests in Iraq, which he has, more or less, reduced to “ISIS bad. Iran bad.” Emboldening moderates in Iraq is consistent with one of the president’s favorite talking points—hedging against Iranian subterfuge. Like ISIS, Iran feeds on sectarian strife and political dysfunction. Michael Singh, the former NSC official, made an emphatic point of this. “An unstable, conflict-ridden Iraq,” Singh told me, “will inevitably be a vector for Iranian power projection, just as Syria, Lebanon and Yemen have been.”

If he had the incentive, Trump could advance a deft Iraq policy without violating the nebulous tenets of “America First.” He could don a veneer of pragmatic national-security ethos and proclaim, with something approximating conviction, that ISIS will never again be allowed safe haven. If he were to revise his “skinny budget,” he’d have at his disposal a blend of military and nonmilitary assets uniquely equipped to render Iraq inhospitable to the insurgents who have cast such an indelible shadow over the American homeland. By funding that recipe’s civilian ingredients and disabusing himself of a “bomb the shit out of ’em” mentality, the president could secure lasting bang for a shoestring buck. In other words, H. R. McMaster must teach Donald Trump how to eat soup with a knife.

Zach Abels is an assistant managing editor at the National Interest.

Image: U.S. Army soldiers in Mosul, Iraq. Flickr/U.S. Army

Note: This article has been updated since its original posting.