In 1968, President Lyndon B. Johnson's election exit shocked Americans

In March 1968, President Lyndon B. Johnson was nearly 40 minutes into a speech on the Vietnam War when he closed with a stunning announcement: He would not seek another term.

From the Oval Office, Johnson said he would not “devote an hour or a day of my time” to any duties beyond his current presidency or accept the Democratic Party’s nomination again.

Johnson’s decision, known only to immediate family and a few close advisers beforehand, shocked Americans who heard his speech that night. Now, experts say some of the forces at play during that race - Johnson’s concerns about his own health, discontent over his handling of the war and competition from fellow Democrats - mirror pressures surrounding President Biden as allies publicly questioned his fitness to serve another term. On Sunday, he announced that he would end his campaign for reelection.

After sailing to victory in 1964 to win his first full term, Johnson realized he would likely experience “a difficult primary” four years later, said Kent Germany, a history professor at the University of South Carolina. He faced formidable challengers from within his own party, and a significant portion of the public disapproved of his policies in Vietnam.

“The immediate message that he was receiving was that there’s not going to be a coronation once again,” Germany said.

Johnson, who had a heart attack in 1955, had considered dropping out of a presidential race at least once before.

During the 1964 Democratic National Convention where he would receive his party’s nomination, Johnson told one of his aides he wanted to withdraw. In a reference to former president Woodrow Wilson’s 1919 stroke, Johnson said he did not “want to be in this place like Wilson,” according to a recording from the LBJ Presidential Library.

“Now, there are younger men and better-prepared men and better-trained men and Harvard-educated men, and I know my own limitations,” Johnson told his aide. “I just don’t believe that I have the physical and mental strength to carry them.”

Johnson’s doubts appear to have been short-lived. Two days after the conversation with his aide, he accepted the Democratic nomination. He went on to defeat Republican Barry Goldwater in a landslide victory.

But Johnson’s concerns became more pronounced in 1968 as he considered a second full term. For years, Johnson had been discussing the prospect of not running again with his wife, Lady Bird. As the election drew closer, he considered his health and the contenders he would face for the Democratic nomination - including Sen. Eugene McCarthy (D-Minn.), who had received 42 percent of the vote to Johnson’s 50 percent in New Hampshire’s Democratic primary.

His health also weighed on him. “He was also, I think, concerned that men in the Johnson family didn’t live very long,” said Fredrik Logevall, a history professor at Harvard University.

In the years leading up to the next election cycle, Johnson’s approval rating drastically declined. Historians say Americans’ dissatisfaction with Johnson’s handling of the Vietnam War was the driving factor behind his decision to exit the race.

“He had committed to this policy of escalation in Vietnam several years before and had literally put the blood of Americans into the soil of Southeast Asia,” Germany said.

Ahead of his March 31, 1968, address about de-escalating the conflict, Johnson had written two versions of his speech - one that included his exit announcement and another that didn’t.

In the end, he told Americans that he had decided he “should not permit the presidency to become involved in the partisan divisions that are developing in this political year.”

“With America’s sons in the fields far away, with America’s future under challenge right here at home, with our hopes and the world’s hopes for peace in the balance every day, I do not believe that I should devote an hour or a day of my time to any personal partisan causes or to any duties other than the awesome duties of this office - the presidency of your country,” Johnson said.

Until that moment, many Americans expected Johnson to continue seeking a second term. After he withdrew, his vice president, Hubert Humphrey, announced his candidacy and won the support of enough delegates to become the Democratic nominee at that year’s convention. Republican Richard M. Nixon ultimately defeated Humphrey and George Wallace, a former Alabama governor who ran as an independent, that November to capture the presidency.

The discussions around Biden’s fitness to serve a second term have been far more public than the conversations about Johnson, Logevall said before Biden’s Sunday announcement.

After Johnson’s speech, Logevall said: “I think people said to each other in their living rooms, ‘Did he just say what I think he just said?’ I think there was a degree of shock that, of course, is very different from today.”

The primary concerns are also different for Biden than they were for Johnson. As he debated former president Trump on June 27, Biden at times struggled to complete sentences, spoke haltingly and appeared confused. Democrats responded with alarm about the 81-year-old president’s mental acuity and ability to serve a second term.

“He can’t do anything to make himself more popular by being younger, right?” Germany said after the debate, more than a week before Biden left the race. “Johnson could have changed policies in Vietnam to make himself more popular, but instead he made the decision to withdraw from the race.”

Still, Johnson’s exit appears to have been a game-time decision, an indicator of his ambivalence toward reelection, Logevall said. Earlier on the day of his address, a former aide recalled in a memoir, Johnson still wasn’t sure what he would do.

“I won’t know whether I’m going to do this until I get to the last line of my speech,” the president said, according to the book.