The concern, as articulated by his Democratic rivals and a wave of harsh online commentary, is that Biden sees contemporary America through a distorting haze of nostalgia, that his values and assumptions were shaped by the last generation or even the one before that, that after many years in public life he still lacks the self-awareness or self-discipline to wonder whether modern voters will find his vagrant ruminations about the past as interesting or relevant as he does…

This doesn’t mean, obviously, that older people can’t get elected president. But they typically must find a way to find the fountain of political youth even in a context of advanced chronological age. One way to do that is by offering oneself as the leader of an ideological movement. This is what Ronald Reagan, age 69, did in winning the presidency in 1980, and it is what Bernie Sanders, age 77, hopes to do this year. The other way older people spring to power is by offering their seasoned characters as perfectly suited to the moment, as Churchill did in wartime England upon becoming prime minster at age 65 and as Dwight Eisenhower in winning the presidency in 1952 at the (old by prevailing standards then) age of 62.

Biden, during 48 years on the national scene, has never had an especially strong ideological profile: He’s been a reasonably centrist Democrat for all of them. When he has deviated it was usually in right-leaning directions, as with his opposition to forced busing ing for integration in the 1970s or his support for expanding crimes covered by the death penalty in the 1990s.