And this is just one reason why you shouldn’t consider electing eightysomething presidents
By 
Former Vice President Joe Biden’s top advisers and prominent Democrats outside the Biden campaign have recently revived a long-running debate whether Biden should publicly pledge to serve only one term, with Biden himself signaling to aides that he will serve only a single term.
While the option of making a public pledge remains available, Biden has for now settled on an alternative strategy: quietly indicate that he will almost certainly not run for a second term while declining to make a promise that he and his advisers fear could turn him into a lame duck and sap him of his political capital.
According to four people who regularly talk to Biden, all of whom asked for anonymity to discuss internal campaign matters, it is virtually inconceivable that he will run for re-election in 2024, when he would be the first octogenarian president.
“If Biden is elected,” a prominent adviser to the campaign said, “he’s going to be 82 years old in four years and he won’t be running for reelection.”The adviser argued that public acknowledgment of that reality could help Biden assuage younger voters, especially on the left, who are unexcited by his candidacy and fear that his nomination would serve as an eight-year roadblock to the next generation of Democrats.
By signaling that he will serve just one term and choosing a running mate and Cabinet that is young and diverse, Biden could offer himself to the Democratic primary electorate as the candidate best suited to defeat Trump as well as the candidate who can usher into power the party’s fresh faces.
“This makes Biden a good transition figure,” the adviser said. “I’d love to have an election this year for the next generation of leaders, but if I have to wait four years [in order to] to get rid of Trump, I’m willing to do it.”
Another top Biden adviser put it this way: “He’s going into this thinking, ‘I want to find a running mate I can turn things over to after four years but if that’s not possible or doesn’t happen then I’ll run for re-election.’ But he’s not going to publicly make a one term pledge.
What could easily happen instead is that Biden gets elected, shows various signs of accelerating decrepitude during his first term, and decides to run for re-election anyway, triggering a brutal intra-party fight.