In 2020, America elected Joe Biden to be not-Trump—a role for which he seemed well-suited. In 2016, the country voted for burn-it-all-down upheaval. Trump was the tribune of those who felt betrayed and misled and mistreated. Four chaotic years later, alarmed voters fled into the arms of an aging former vice-president and senator—a man they had twice rejected as a presidential contender—who seemed the personification of the steady hand. No one expected Biden to be transformational or extraordinary, but we did need him to be the anti-Trump in the most important ways. We needed him to be sober and responsible,...