WASHINGTON — Secretary of State John F. Kerry’s career has long been intertwined with Vietnam, and the devastating, divisive war he fought in and against.

After a tour in Vietnam as a young Navy officer, Kerry burst onto the public stage as an antiwar protester in the 1970s. As a senator, he helped create conditions for the normalization of US-Vietnam relations in the 1990s. Next month, he will accompany President Obama to Hanoi, no longer Washington’s foe but an important strategic and economic partner.

Kerry’s past and present will merge once again Wednesday at a Vietnam symposium at the LBJ Presidential Library in Austin. He will preview the Obama trip, and chat onstage with filmmaker Ken Burns about Burns’ upcoming documentary on the Vietnam War.

Some commenters already have taken to social media to criticize the secretary of state’s appearance.

‘‘Are you kidding, you invited John Kerry???? Might as well bring on Hanoi Jane as well!!!!’’ one man wrote after the Vietnam Veterans Memorial Fund posted a notice about the summit on its Facebook page.

‘‘No one cares about Kerry, why invite him?’’ wrote another. ‘‘That alone is a reason to stay away from the Summit.’’

The event is likely to underscore how contentious the conflict remains 41 years after it ended ignominiously with an airlift from the US Embassy rooftop.

‘‘The feelings related to almost everything connected to Vietnam are still very raw,’’ said Jim Knotts, president of the Vietnam Veterans Memorial Fund. ‘‘There are some people who feel as strongly against war today as they did in the late ‘60’s and early ‘70s. There are some who feel just as strongly they never want to be in a room with people who protested against the war.’’

Kerry is not the only participant under criticism. Some students at the University of Texas are calling for pickets to protest Henry Kissinger, who was secretary of state during a particularly bloody stretch in the long war. The event also will include political activist Tom Hayden, who is famous for going to Hanoi with his then-wife, actress Jane Fonda, in 1972 to commiserate with peasants whose dikes had been bombed.

The library has reached out to service organizations, hoping hundreds of Vietnam veterans will attend, not just as participants but as honorees.

A commission established by Congress to commemorate the war will hand out lapel pins to veterans. Lynda Johnson Robb, the older daughter of Vietnam-era president Lyndon B. Johnson and the wife of Vietnam veteran and former Virginia governor Chuck Robb, will help distribute the pins.

Robb said she has been reading the letters her husband wrote her from the war zone, remembering how her father got up in the middle of the night to pray that the fighter jets would return safely. Vietnam, she said, ‘‘destroyed my father’s hopes and dreams for his domestic programs.’’

‘‘This is an opportunity to honor and recognize our Vietnam veterans, who didn’t get the recognition they deserved,’’ she said of the symposium that she and her sister, Luci Johnson, will attend. ‘‘There are a lot of people that are coming to the end of their lives, and we want to thank them for what they did.’’

Knotts said some veterans remain angry with Kerry because of their experiences when they came home from the war.

‘‘It stems from the fact that many of the Vietnam vets when they came home were told to hide the fact they were vets,’’ he said. ‘‘It was to save themselves grief, mistreatment, negative attitudes, not getting hired in jobs, a general community stigma related to the war. They feel that they should have been honored for their service to country regardless of people’s feelings about the war.

‘‘So now they are unfettered. They feel they will not be kept from expressing opinions the way they were when they first came home.’’

Joe Galloway, a former war correspondent who co-wrote a book about a key battle, ‘‘We Were Soldiers Once . . . and Young,’’ said it made sense for Kerry to appear at the event.

‘‘Kerry has all the reason in the world to be there,’’ Galloway said. ‘‘He was a Vietnam vet. He served honorably. He came home, he was against the war. So were a lot of vets.’’

The venue for this particular symposium is both an apt and an awkward fit. President Johnson’s achievements in civil rights legislation, heralded in a similar seminar at the library two years ago, were overshadowed by the grinding war.

When the LBJ Library was dedicated in 1971, Johnson said it illustrated the story of his time in office, ‘‘with the bark off.’’

Said Mark Updegrove, the library’s director. ‘‘If we looked at the triumph of civil rights, we have to look in the same comprehensive, unvarnished way at the trajectory of Vietnam. We are not in the business of hagiography. It was LBJ’s hope that his presidential records would be processed as soon as possible and give people a sense of what he did in the course of his tenure, and make of it what they will.’’

In his speech, Kerry may reprise a theme he repeats often around the world, that diplomacy should be exhausted before young men and women are sent to war.

‘‘The United States and Vietnam have again proven that former adversaries really can become partners, even in the complex world we face today,’’ he said during a visit to Hanoi last year. ‘‘And as much as that achievement matters to us, it is also a profound and timely lesson to the rest of the world.’’