First, why exactly did he choose to fight? Why would someone who publicly professed (as Kerry did as a college student) great skepticism about the war, volunteer–not only to serve, but also to take on one of the Navy’s most hazardous assignments, engaging the Viet Cong in the Mekong Delta? And why, once in theater, did he fight with such boldness that he earned a chest full of medals and the admiration of his more gung-ho colleagues?

In his new book, popular historian Douglas Brinkley provides a wealth of material to intensify this debate. He has mined Kerry’s wartime correspondence; interviewed friends, family, fellow veterans, and the senator himself; and woven together a fascinating (and flattering) tale of Kerry’s Vietnam years. Yet, the book provides no definitive answer to these questions; Kerry’s motives and reasons, then as now, remain complex.

The second big question is why, after having fought the war so energetically, did he go on to protest it with equal vigor? Here, the book gives a much clearer answer: Kerry’s Vietnam experience fully confirmed his earlier suspicions. The particular combat missions his superiors sent him on were–like the war as a whole–ill-conceived, bloody, and pointless.

“I have been thinking a lot about Vietnam and the reasoning of the uncommitted soldiers,” Navy Ensign John Forbes Kerry wrote his parents early in 1968. “How one can oppose the war and still fight it?”

Kerry at the time was serving in the Pacific aboard the destroyer USS Gridley. A few days after writing this to his parents, he learned that his best friend, Dick Pershing, grandson of famed World War I general “Black Jack” Pershing, had been killed in combat in Vietnam. Kerry was devastated, writing to Julia Thorne, who would become his first wife, that he was prepared to do everything he could “to bring to people the conviction of how wasteful and asinine is a human expenditure of this kind.”

Yet instead of rounding out his service in the relative safety of the Gridley, Kerry volunteered to command one of the little boats called Swifts, and so went face-to-face with the Viet Cong. The Navy didn’t offer many assignments more dangerous than that. Why did he do it?

Much of what moved him was straightforward patriotism–“[H]e came to realize that now, more than ever, he had to perform his own duty to his country,” Brinkley argues, “even if it meant dying in the waters off South Vietnam.” Kerry also felt a surge of fury over Pershing’s death. The enemy had killed his friend, “and he was ready to kill them if he had to,” Brinkley says.

But there were yet other reasons. Kerry, notes Brinkley, was a “qualified risk-taker … He enjoyed ‘extreme’ sports before they had the name: downhill racing, surfing, parasailing, full-impact ice hockey, motorcycle riding, you name it,” and also felt, Brinkley believes, “inexplicably drawn to combat.” Like many a young man, he wanted to know how he would react under fire. But what most comes across in Brinkley’s telling is Kerry’s abiding intellectual curiosity. He wanted to know everything he could about war generally, and the Vietnam conflict in particular. He read voraciously, everything from Erich Maria Remarque’s World War I trench warfare novel, All Quiet on the Western Front to the latest Vietnam dispatches from journalists like Neil Sheehan and David Halberstam. He kept a detailed diary of time in the service, often tape-recording his thoughts and observations, with some idea of eventually writing a book about his experiences.

Like his hero, John F. Kennedy, the Brahmin-born Kerry had a passion for small craft, having learned the art of sailing as a teenager along the Cape Cod coast. (Indeed, during his senior year in high school, while dating Jacqueline Kennedy’s half sister, Kerry spent a memorable afternoon watching the America’s Cup race with the president aboard the Kennedy family yacht.) Swift boats bore more than a passing resemblance to the PT boats Kennedy had piloted in World War II. “Although built a generation apart, both crafts were speedy and versatile,” writes Brinkley. “Either could afford the young officer in charge a chance to test his seafaring mettle, without too much supervision–to be of the U.S. Navy, but also apart from it.” Upon seeing a Swift boat for the first time, in Danang harbor, Kerry admitted in a letter to his parents, “I thought jealously of my own desires to have one.”

The parallels between Kerry and Kennedy–both of them JFKs, both Ivy Leaguers, both senators from Massachusetts, both Navy combat heroes–are indeed eerie. But seemingly small differences between the crafts they commanded suggest big differences between the wars they fought. Kennedy’s now-legendary wooden-hulled PT-109 was designed and built with a specific purpose: to torpedo and sink enemy ships, the larger the better. The aluminum-hulled Swift boats, by contrast, were designed and built in a hurry by a company that specialized in water taxis for offshore oil rigs. They were eventually used for combat purposes, for which–despite the addition of three .50-caliber machine guns–they had never been seriously intended.

The Swifts carried a skipper and a crew of five. Kerry commanded two such boats, PCF-44 and PCF-94 (PCF stood for “patrol craft, fast”). The Swifts were first deployed in Vietnam as coastal patrol boats–a not unreasonable function. Kerry saw some of this duty, but it bored him, and he soon volunteered for a more exciting (and hazardous) assignment: taking Swifts into the rivers and canals of the Viet Cong-controlled Mekong Delta.

In charge of the campaign, dubbed Operation Sealords, was a figure straight out of Catch-22, Capt. Roy Hoffman. According to Brinkley, Hoffman “sought to convince his Swift boat skippers to do whatever it took to notch splashy victories in the Mekong Delta and thereby get him promoted.” Up until Hoffman’s arrival, Swift boat crews had broken the monotony of routine offshore patrols by dashing up the Mekong Delta distributaries, in areas swarming with Viet Cong, with guns blazing, just for sport. To Hoffman, it was a lot more than that–seeing in such theatrical operations his path to success and glory, he made those hell-for-leather dashes the key part of the little boats’ mission.

Kerry came almost immediately to understand–as did almost everybody assigned to the Swift boats–that there was no point to these mad runs. The boats had no armor to protect them from enemy fire. They were accompanied by no infantry, save for occasional Navy SEALs hitching rides. Without infantry support, there was no chance of occupying Viet Cong territory or running down significant numbers of VC soldiers. The boats’ engines were so noisy that when the wind was right they could be heard coming from three miles away, and, perhaps for that reason, had enormous trouble running down junks and sampans infiltrating weapons to the enemy. “For anyone wanting to smuggle contraband, we actually made the task easier,” Kerry confided in his journal. “All they had to do was hide in a mangrove or in a small canal until we had passed by.” The fact is, Kerry confessed, in all the time he served in his two Swift boats in Vietnam, he and his men never tracked down any contraband–not so much as a single rifle cartridge.

This was the U.S. Navy’s second riverine war, the first being the Civil War, when Gen. Ulysses S. Grant, among others, used river gunboats to soften up Confederate forts and artillery positions. But these were big, powerful boats–175 feet long, 52 feet wide, covered with steel plates almost three inches thick and armed with 13 guns, including 9- and 10-inchers, yet drawing only six feet of water. It is not too foolish to wonder if, with some adaptations (machine guns instead of heavy artillery, and modern engines), Grant’s boats might not have been more suited to the Mekong Delta than the small, unprotected Swifts.

At one point, six Swift boats, Kerry’s included, were ordered to move up to the Bo De River by way of lesser rivers and canals, whence, it was hoped, they could break away to safety. “Nothing I had ever heard of seemed so tactically stupid,” Kerry wrote. The boats were ambushed, took casualties, but still managed to complete the mission, doing nothing to discourage the enemy. It was all part of a pattern.

At one point, Kerry participated in an operational assessment in Saigon presided over by Adm. Elmo Zumwalt, and reports that he asked how, “if our job was ostensibly interdiction of supplies, they could justify offensive operations such as we had been sent on?” Kerry was told the purpose was to show the flag–the American flag. Wouldn’t it be better, he wondered, if we showed the flag of South Vietnam, seeing that was who we were fighting for? Indeed, the newly-elected President Richard Nixon had changed the war’s strategy to one of “Vietnamization.” But Kerry knew the answer. He had seen firsthand how risk-averse and unmotivated the South Vietnamese soldiers and sailors generally were. Vietnamization was nonsense.

Meanwhile, Operation Sealords kept right on going, at an even more frenzied and meaningless pace. In one of the sorties, Kerry, now in command of PCF-94, felt a piece of hot shrapnel from a rocket-propelled grenade dig into his left thigh–the second of his three wounds, none of them life-threatening.

Though he doubted that the war could be won, and by now felt certain his role in it was wasteful and idiotic, he and PCF-94 fought on with astonishing valor and even foolhardiness. In one of the operations, sensing an enemy ambush, he grounded his boat, took off with an M-16 rifle, and ran down and killed a VC trying to arm a B-40 rocket launcher before he could fire. “He (Kerry) saved the day and our lives,” Fred Short, one of his crewmen, said. Kerry won a Silver Star for his valor, pinned on his chest by Admiral Zumwalt himself.

He won a Bronze Star later for reversing his boat, under fire, to pick up an Army officer who had fallen overboard. He got a small piece of a grenade “in my ass” from one of the explosions, earning him his third Purple Heart and a pass to go home.

“By any standard,” says Brinkley, “John Kerry had become a bona fide war hero.” And so he had, in a war he opposed and in a role he thought to be ludicrous. There is no example in American history that I can think of, in which a future presidential candidate fought with such valor for a cause so obviously perverse in his own mind. Maybe Grant, who opposed the war against Mexico but fought in it nevertheless. But then Grant was a West Pointer who took orders as a matter of course. Nothing compares to John Kerry, who came home, shed his uniform, and campaigned against the war with the same passion he had displayed in fighting it.

In spite of the danger and madness of the mission, Kerry in many ways loved the experience. He was a product of an elite boarding school (St. Paul’s) and an elite university (Yale). In his entire life, he had never mingled with such a collection of working-class Americans. The men who served with him came to admire, respect, and, in time, from all indications, love him. They show up with him now on the stump, and their presence animates him. They do represent a band of brothers, and that speaks volumes for his character. Only John Kerry could explain why he fought with so much courage and intensity in a war he despised. Duty, certainly; ambition, perhaps. But so he fought, and we owe him something for it.

James M. Perry was for many years a political writer with The Wall Street Journal. His most recent book is Touched with Fire: Five Presidents and the Civil War Battles that Made Them.

James M. Perry was for many years a political writer with The Wall Street Journal. His most recent book is Touched with Fire: Five Presidents and the Civil War Battles that Made Them.