Rosa Brooks is a professor at Georgetown University Law Center and the author of "How Everything Became War and the Military Became Everything."

KNIFE FIGHTS

A Memoir of Modern War in Theory and Practice

By John A. Nagl

Penguin Press. 269 pp. $27.95

In the U.S. military, as in the fashion world, there are trends and fads, and woe betide the poor sap still clad in last season’s styles. Less than a decade ago, counterinsurgency doctrine (COIN, to aficionados) was the hottest thing going in military intellectual circles. But years of inconclusive conflict in Iraq and Afghanistan turned COIN — with its emphasis on population protection and the establishment of legitimate and effective governance structure — into the military equivalent of Benetton sweaters and Guess jeans: expensive, unflattering and more than a little embarrassing.

‘Knife Fights: A Memoir of Modern War in Theory and Practice’ by John A. Nagl (Penguin)

All this makes it a tough moment for the publication of John A. Nagl’s memoir “Knife Fights,” which offers an unapologetic defense of counterinsurgency. Nagl — now a retired lieutenant colonel and the headmaster of the Haverford School — was an early and passionate COIN advocate. Entering West Point in the early 1980s, he joined a post-Vietnam Army determined to avoid messy and ambiguous conflicts. As a young lieutenant in a tank company during the Persian Gulf War, he watched in awe as the U.S. military made short work of the Iraqi Army. “By God, we’ve licked Vietnam syndrome once and for all!” a jubilant President George H.W. Bush declared.

For Nagl, however, the triumph was short-lived: A year after Desert Storm, he found himself at the Army’s National Training Center in California, pitted in a simulated battle against an infantry company from the Alaska National Guard. Nagl’s tankers assumed they would easily prevail against the ragtag Alaskans, many of whom barely even spoke “understandable English.” Instead, the “Nanooks,” as Nagl’s tankers dubbed the Alaskans, “crept up on us from behind, infiltrating through the mountains that protected our flanks and rear from enemy armored vehicles but not from Eskimos. Methodically, one by one, the Nanooks defeated a dug-in tank company. . . . M1A1 tanks that only a year earlier had defeated the world’s fourth largest Army on its home turf” were defeated “by small bands of human enemies whose language we could barely understand but who knew our vulnerabilities.”

The experience left Nagl determined to gain a better understanding of insurgencies and irregular warfare. He went back to graduate school at Oxford, where his 1997 dissertation, “Learning to Eat Soup with a Knife,” focused on counterinsurgency lessons from Malaya and Vietnam. Back in the United States, he struggled to find a publisher: “No one was interested in a book on how armies learn to succeed in counterinsurgency.”

That changed during the Iraq War. Faced with a baffling and unexpected resistance instead of the anticipated cakewalk, many U.S. military officers began to have their own version of Nagl’s epiphany after his defeat by the Nanooks. Suddenly, counterinsurgency was all the rage, and his dissertation, which had finally been published, became an instant COIN classic. In 2006, Nagl was tapped by Gen. David H. Petraeus to help draft the Army’s first counterinsurgency manual. It became an improbable bestseller, garnering a fulsome review in the New York Times and catapulting Nagl onto Jon Stewart’s “Daily Show.”

But COIN’s ascendancy proved as short-lived as the post-Gulf War sense of triumph. The 2008 financial crisis made open-ended U.S. military commitments seem increasingly unaffordable, and President Obama made it clear that his goal in Iraq and Afghanistan was the withdrawal of U.S. combat forces, not an extended counterinsurgency presence. Talk of counterinsurgency soon gave way to talk of counterterrorism drone strikes: a quick, cheap and seemingly risk-free way to get rid of the United States’ enemies.

By 2012, COIN’s moment was over. Its critics declared it too expensive and too uncertain, viewing COIN’s emphasis on protecting the population and building effective governance as a dangerous distraction from the core military task of destroying the enemy. “Counterinsurgency as an operational method . . . has failed miserably,” Army Col. Gian Gentile concluded in 2013. “Counterinsurgency is dead.”

In “Knife Fights,” Nagl offers both a defense of COIN’s core insights and a stern warning that more is at stake here than the latest military fads. “There is no sign that the future holds anything but a continuation of [the recent] trend towards less conventional conflict and more insurgency and counterinsurgency,” he declares, and if today’s military deemphasizes counterinsurgency skills, it does so at its own peril. (To paraphrase Leon Trotsky’s famous aphorism about war, you may not be interested in insurgencies, but insurgencies are interested in you.)

To Nagl, Iraq and Afghanistan are stories of missed opportunities and early mistakes that were never rectified, and COIN’s failures have less to do with COIN than with the military’s dysfunctional culture. In both Iraq and Afghanistan, the United States adopted counterinsurgency approaches only as an afterthought, and COIN remained a shallow overlay on entrenched military training and practices. The military never truly invested in building the “cultural competence, linguistic skills and organizational learning” required for successful counterinsurgency operations, and a rigid, unforgiving personnel and promotion system meant that officers who challenged prevailing assumptions or tried creative new approaches often found themselves routed into dead-end assignments.

Nagl’s fate is instructive: In 2006, with the new COIN manual about to hit the press, the Army assigned him to a non-deployable tank battalion at Fort Riley, Kan. It was “the kiss of death” for his Army career. “I would never leave Kansas in an operational role,” he writes ruefully. “Missing the chance to command in a war that had been the sole focus of the past three years of my life was a blow from which my love of the Army never fully recovered.” In 2008, he did what too many of the Army’s most creative young officers have done: He retired.

Nagl’s implicit warning is clear: If the U.S. military cannot find a way to become more self-reflective and adaptive, it will continue to draw only the most superficial and misleading lessons from the conflicts in which it finds itself. After Vietnam, the military turned its back on counterinsurgency and irregular warfare; the Gulf War then created a false sense of confidence in conventional capabilities. In Iraq and Afghanistan, the pendulum briefly swung back toward COIN and unconventional warfare, before these were again repudiated, this time in favor of a standoff approach to conflict that relies mainly on airpower and high-tech intelligence and surveillance.

Ultimately, “Knife Fights” is a cri de coeur: In an uncertain, dangerous and ever-changing world, the U.S. military stands at a crossroads. It can focus on becoming a genuine learning organization — one that’s flexible, agile and tolerant of ambiguity — or it can stay as it is, continuing to oscillate self-destructively from fad to fad.

Rosa Brooks is a senior fellow at the New America Foundation and a law professor at Georgetown University. From 2009-11, she served as a senior advisor to the undersecretary of defense for policy.

KNIFE FIGHTS

A Memoir of Modern War in Theory and Practice

By John A. Nagl

Penguin Press. 269 pp. $27.95