History isn't kind to one-term presidents, at least in the short run.
For most of the last 40 years, Jimmy Carter's presidency has been widely remembered as an epic failure, the cautionary tale of a politician who was soundly rejected by voters when he sought a second term in 1980.
Happily for Carter, 98, who entered hospice care this month, his reputation has since risen, thanks to his admirable post-presidency and biographies that have reassessed his record more favorably.
Carter's presidency, they argue, was better than it looked. He enacted historic environmental legislation, including the first federal funding for renewable energy. He deregulated airlines, making air travel more affordable. He made human rights a central theme of U.S. diplomacy and negotiated landmark peace accords between Israel and Egypt.
But by the time he sought reelection, inflation had soared past 12%, the economy was heading toward recession and voters wanted a change.
After his loss to Ronald Reagan, Carter was a prophet without honor, even in his own party. He was uninvited to Democratic conventions and rarely mentioned by his successors.
Joe Biden witnessed all of it up close. In 1976, Biden, then 33, was a thoroughgoing Jimmy Carter Democrat. He was the first U.S. senator to endorse the former Georgia governor's presidential candidacy. He backed Carter again in 1980, when the then-president faced a bruising primary against the more liberal Sen. Edward M. Kennedy of Massachusetts.
What lessons did Carter's tenure teach Biden, who was already thinking about running for president?
First, politics is important, beginning with managing your own party's coalition. Carter failed spectacularly on that score. He disdained bargaining with members of Congress and often didn't even return their calls.
"Carter thought politics was sinful," his vice president, Walter Mondale, said. "The worst thing you could say to Carter if you wanted him to do something was that it was politically the best thing to do."
Even as a first-term senator, Biden saw that was a problem.
"The president is learning, but not fast enough," he said in 1977. "Nixon had his enemies list and President Carter has his friends list. I guess I'm on his friends list, and I don't know which is worse."
When Carter ran into trouble, he was left with few allies. Democrats in Congress helped kill several of his top legislative priorities, including health care and tax reform bills.
Biden is the opposite — a relentless schmoozer who began his 2020 presidential campaign by knitting his party's moderate and progressive wings together.
In his first two years as president, Biden focused on managing unruly Democratic majorities in Congress and passed major bills on climate change, infrastructure spending and semiconductor production.
Second, Carter's troubles reaffirmed an ancient political truism: In an election year, the economy — especially inflation — trumps every other issue.
Carter signed landmark legislation, but once voters encountered gasoline shortages and inflation soaring above 12%, none of it seemed to matter.
He responded to economic crisis by proposing an austerity budget and appointing an inflation hawk, Paul A. Volcker, to run the Federal Reserve. Volcker pushed interest rates up to 20%, which eventually tamed inflation. But by then, Carter was a private citizen back in Plains, Georgia.
Biden is presumably hoping his Fed chair, Jerome H. Powell, will be gentler as he tries to steer the economy to a soft landing before the 2024 election.
Meanwhile, the president isn't embracing Carter-style austerity. Instead, he's touting his administration's spending on infrastructure and manufacturing jobs.
A third lesson from Carter's fall: Foreign policy success may not help a president's reelection prospects, but foreign policy failures will hurt.
Carter concluded a major nuclear arms agreement with the Soviet Union, normalized diplomatic relations with China and negotiated the Camp David accords, ending the threat of major war between Israel and its Arab neighbors.
But when he ran for reelection in 1980, the only international issue that mattered to most voters was Iran's seizure of 52 American hostages, a problem Carter failed to solve.
Afterward, Carter said he was "one helicopter short" of winning, a reference to the mission's failure. His loss had many causes, but that episode probably doomed his chances.
Biden's biggest foreign policy success — his leadership of a coalition opposing Russia's invasion of Ukraine — doesn't appear to have bolstered his approval ratings; they've been stuck around 43% for the last six months.
But at least Ukraine has displaced the public's memory of the botched U.S. withdrawal from Afghanistan in 2021.
If Biden does run for a second term, as he says he intends, Carter's life may offer one more lesson: The voters' verdict isn't always the last word — win or lose.