Rosa Brooks is a law professor at Georgetown University, a former State Department and Pentagon official and the author of “How Everything Became War and the Military Became Everything.”

Ronan Farrow’s “War on Peace: The End of Diplomacy and the Decline of American Influence” is more an elegy than a work of journalism, more a work of journalism than a history of diplomacy, and more a history than a sustained analysis of the value and effect of U.S. diplomacy. Farrow’s overarching argument is straightforward: America needs diplomats, those “specialized experts trained in the art of hard-nosed negotiation” who can provide “thoughtful, holistic foreign policy analysis, unshackled from military contingencies.” But for decades — beginning, in Farrow’s telling, with the administration of President Bill Clinton and accelerating dramatically under President Trump — America has been overvaluing the military and undervaluing diplomacy, to its own detriment.

Although “War on Peace” doesn’t fully achieve its broadest ambitions, it offers lively writing, astute commentary and plenty of great stories, laced through with passion and outrage. The book’s first half is mostly a wry, extended tribute to the late Richard Holbrooke, for whom Farrow worked as a junior staffer in 2009-10, while Holbrooke served as U.S. special representative for Afghanistan and Pakistan. Famously abrasive and self-centered, on the surface, Holbrooke hardly seemed to exemplify the suave, urbane diplomats of cinematic and literary fantasy. His inappropriateness remains the stuff of legend: Once, determined to get the last word in an argument, he even followed then-Secretary of State Hillary Clinton into a ladies’ restroom in Pakistan.

Farrow’s own job interview with Holbrooke also involved toilets: After a desperate effort to keep up while Holbrooke raced through the State Department’s corridors, barking at aides and taking calls on his BlackBerry, Farrow eventually found himself following Holbrooke into his Georgetown townhouse, where Holbrooke proceeded to grill him about the Taliban while peeing behind a half-closed bathroom door.

And yet, as Farrow’s unsparing but affectionate portrait reminds us, Holbrooke was, for all his bluster, the ultimate practitioner of the dying art of diplomacy, that slow, often tedious project of engaging both with allies and with enemies, and seeking to avoid or resolve conflict. Holbrooke was maddening and obnoxious, but somehow his methods often worked. He was, Farrow concludes, “the rare asshole who was worth it.”

Holbrooke’s signature achievement remains the 1995 Dayton agreement, which brought a negotiated end to the brutal wars that racked the former Yugoslavia in the early 1990s. Like all products of diplomacy, admits Farrow, the Dayton agreement was “an imperfect document.” It ceded “almost half of Bosnia . . . to the Serbian aggressors, essentially rewarding their atrocities.” Still, it “succeeded in ending three and a half years of bloody war.”

The diplomat’s job, as Farrow relates it, is often difficult, tedious and infuriating: “Hammering out deals between governments . . . can sometimes give the job the feel of Thanksgiving dinner with your most difficult relatives, only lasting a lifetime and taking place in the most dangerous locations on earth.” (Farrow has some difficult relatives of his own. The reader is left to imagine the scene and wince in sympathy.) But Holbrooke thrived on “difficult.” No issue was too large or small. When Holbrooke decided that agriculture — particularly, the production of pomegranates — was the key to Afghan stability, Farrow found himself presiding over “dozens of meetings focused on the fruit.” Sometimes, he recalls, Holbrooke would cut him off in the middle of an unrelated sentence, demanding, “Where are we on the pomegranates?”

But U.S. diplomacy isn’t all toilets and pomegranates. In the second half of “War on Peace,” Farrow provides a tour through some of the other highs — and lows — of recent American diplomacy, from Plan Colombia (which, despite an inauspicious start, eventually poured $10 billion into Colombia and helped bring an end to that country’s decades-long civil war) to the Obama administration’s disastrous misreading of Egyptian politics in the wake of the Arab Spring. Farrow’s message throughout is simple: Diplomacy is imperfect and unsatisfying but essential. When we underinvest in it or value military imperatives more highly, we — and the world — suffer.

Running through the book is the story of Ambassador Robin Raphel, who worked over the course of her distinguished career in trouble spots from Iran and South Africa to Tunisia and Pakistan. Unlike the rough-edged Holbrooke, Raphel was a diplomat from central casting: She had “an aristocratic quality,” writes Farrow, and spoke with “the clipped, mid-Atlantic cadence of a 1940s movie star.” Erudite and tough as nails, Raphel believed in “an old-fashioned diplomatic maxim: you never stop talking.” She favored dialogue with the Taliban, and maintained informal back channels to Pakistani military and intelligence officials even during the tensest moments in U.S.-Pakistani relations.

Her dedication to diplomacy was almost her undoing. In 2014, the Justice Department opened an espionage investigation into Raphel’s activities: An intercepted Pakistani cable apparently referred to her as a “source” of information on classified U.S. plans. The FBI raided her home and office, and she lost her security clearance. But after two years, the Justice Department dropped the investigation, vindicating Raphel’s claims of innocence.

“The FBI investigation flowed from multiple layers of misunderstanding,” writes Farrow. “Anyone who had ever spent five minutes at a dinner party in Islamabad” knew that many “nominally ‘classified’ topics,” such as U.S. drone strikes, “were an unavoidable matter of public debate” in Pakistan. The FBI’s counterintelligence investigators — more familiar with electronic surveillance than with diplomacy — had delayed interviewing Raphel’s State Department colleagues, because they didn’t want to tip her off. When they finally spoke to her colleagues, they were surprised to find that what they saw as Raphel’s “incriminating behavior” with foreign contacts was viewed inside the Foreign Service as “simply old-school, relationship-driven diplomacy.”

In “War on Peace,” Raphel serves both as an examplar of the art of the diplomacy and as a cautionary metaphor: When a nation ceases to understand or value its diplomats, the tools of diplomacy become so unfamiliar as to seem actually criminal.

The Trump administration represents the apotheosis of this trend, and Farrow’s final chapters focus on Trump’s gleeful dismantling of what remains of America’s diplomatic apparatus. Under this president, deep budget cuts and hiring freezes have crippled the already demoralized State Department; the surfeit of military voices in Trump’s Cabinet has sidelined the remaining civilian foreign policy officials; and from NAFTA to the Iran nuclear agreement, many of the alliances and treaties so carefully nurtured by diplomats in prior administrations have been mocked or sent to the shredder. Meanwhile, U.S. global influence is waning, and “Beijing looms large behind a retreating Washington.”

Like Farrow, I’m dismayed by the negligent casualness with which successive presidential administrations have handed ever-larger swathes of U.S. foreign policy over to the military, and disgusted by the Trump administration’s contemptuous devaluing of the dedication and expertise of America’s career diplomats. But Farrow’s conviction that traditional diplomacy is a “life-saving discipline” requires more analysis than he offers.

Was America truly better — richer, more peaceful, more successful on the global stage — when its diplomatic institutions were more robust? Maybe, maybe not: Farrow doesn’t tease out cause and effect, and it is worth recalling that old-school diplomats didn’t manage to prevent two successive world wars, keep the United States out of Korea or Vietnam, or stop the Cold War from fueling vicious internal conflicts throughout Africa, Asia and Latin America. If the United States had more global influence in past decades, was this because of the skillfulness of its diplomatic corps or the strength of its military and economy? Conversely, if U.S. global influence is now declining and the United States has recently plunged “into military engagements that might have been avoided,” is the decline of traditional American diplomacy really the primary cause?

“The point,” asserts Farrow, “is not that the old institutions of traditional diplomacy can solve today’s crises. The point is that we are witnessing the destruction of these institutions, with little thought to engineering modern replacements.” Perhaps it’s this that troubles him most: not nostalgia for a vanishing past but the sheer wanton waste of it all.

“War on Peace” is full of telling anecdotes and wry, witty observations. If it doesn’t entirely hang together as an argument, it still makes for enjoyable and occasionally compulsive reading: Farrow is a natural storyteller, and his empathy and imagination breathe life even into the endless, awkward Thanksgiving dinner that constitutes diplomacy. In the end, “War on Peace” is much like Farrow’s characterization of diplomacy itself: rich, messy and imperfect, but ultimately, more than worth it.

War on Peace

The End of Diplomacy and the Decline of American Influence

By Ronan Farrow

Norton. 392 pp. $27.95