A new, 18-hour Vietnam documentary revisits the war. | Wikimedia Commons

The 18-hour documentary series “The Vietnam War” opens with Bob Dylan’s “A Hard Rain’s A-Gonna Fall,” setting the tone of casual American optimism at the outset of the ’60s. But it transitions to an admission of defeat: “America’s involvement in Vietnam began in secrecy,” the narrator intones. “It ended, 30 years later, in failure, witnessed by the entire world.”

This is not a new thesis, but the documentary delivers it in a way nothing has before. The narrator and dozens of interviewees invoke it consistently, and the general arc of the story is familiar: By Episode 6, North and South Vietnam have split, American soldiers are losing optimism, and Lyndon Johnson is begging his advisors, in hapless good-ol’-boy tones, to do something. Anything. The final four episodes follow this tailspin.

The documentary directed by Ken Burns and Lynn Novick began airing on PBS this September, and is available for streaming on the channel’s website. Burns and Novick collected tens of thousands of photographs, videos, and audio from all sides of the conflict to immerse Americans in what he called “a war we have consciously ignored.”

The documentary succeeds stylistically, in classic Ken Burns style: the interviews personal and probing, the music (by Trent Reznor and Atticus Ross) ominously optimistic and harrowing by turns, the images arresting thanks to the “Ken Burns effect,” and the cinematography characterized by the slow pan-and-zoom that has been the director’s trademark since early in his career.

“The Vietnam War” is not a pleasant viewing experience. The original optimism for the war unraveled quickly; in the first few episodes, Vietnam spirals into brutal violence and hatred on both sides. North and South Vietnamese leadership splinters, and Americans find that guerilla warfare is something different than they imagined.

“We think about how many times we get ourselves in scrapes as a nation because we’re always the good guys,” ex-marine Karl Marlantes said. “Sometimes I think if we thought we weren’t always the good guys, we might actually get in less wars.”

Interviews with veterans — doctors, advisers, men on the ground; Americans, French, Vietnamese — give the documentary poignancy and depth. Veterans John Musgrave, Roger Harris, Dennis Stout, and 76 other witnesses of the war share first-person accounts, voice regrets, and likely reopen the war’s wounds. There are no Vietnam scholars; Burns has no time for talking heads.

“My take on the Burns piece is that [the documentary] was highly informative, at the very least, and fairly straightforward and even-handed,” Hillsdale College Professor of History Thomas Conner said. “The biggest benefit I can see in it is that it brought the Vietnamese perspective greatly to light — the politics, and most of all, their suffering. It’s easy for us Americans to point to the terrible toll in blood that we paid — nearly 60,000 dead.  But, to the Vietnamese, the toll was immensely higher, probably to be numbered in the millions, and our focus generally has not been on that.”

In his personal and often provoking interviews of veterans from both sides, Burns leaves — and always has left — space for emotional reactions to and re-creations of defining American experiences. For Burns, this is history: crafting a national narrative of perplexing or overlooked experiences that haunt the cultural conversation. In a September profile of Burns’s career, the New Yorker’s Ian Parker traced the director’s ouevre and found a common thread. Burns’s subjects are classic American themes: baseball, the Civil War, the Brooklyn Bridge in New York. Burns tells America’s stories, for Americans, in the voices of Americans.

Burns proposes no new academic theories, maybe, but he asks for an American reckoning. And the consensus in many of the documentary’s interviews seems to be that American involvement in Vietnam was a mistake. The task for America, through Burns, is to come to terms with the fallout. Burns claims it is time to raise the curtain of taboo, to bring Vietnam into the light of national conversation.

While almost 20 hours of footage deepens our historical understanding, it merely adds another layer to an ongoing conversation: The shadow of Vietnam never moved, haunting for half a century our conversations about the American government’s role in global politics.

For Conner, Burns’s focus on the failings of Vietnam-era leadership is not bias; it’s been an integral part of the debate since the beginning.

“Burns was properly critical of the American government when it most deserved criticism, and as one who lived through that era, I was quite impressed by his effort to portray the Vietnam war for everything that it really was, to all concerned,” Conner said.

Since the 1960s, the debate has raged: Was involvement in Vietnam a mistake, a result of incompetence, or an outworking of American overconfidence and lust for power?

According to the documentary, the answer to those questions seems to be, “Yes. All of the above.” It remains for the American people to voice their regrets and move on, or at least to understand what went wrong in Vietnam, and why.