If President-elect Biden is serious about healing a divided nation, he will have to take steps that won’t be popular in his own party. For example, he won’t encourage the Justice Department to open investigations that could lead to the prosecution of Mr. Trump. If Mr. Trump’s infamous “lock her up” chant is met with calls to “lock him up,” the country will have taken another step toward the criminalization of political conflict—a hallmark of banana republics.

A Biden presidency that puts healing first will govern from the center, as Ford did. Mr. Biden should lead off his legislative agenda on areas where bipartisan agreement should be possible, such as a national plan to ensure speedy vaccine distribution and adequate supplies of personal protective equipment. He should resist promoting steps, such as a national mask mandate, that are bound to provoke political controversy and constitutional challenges. He can instead work with the National Governors Association and set out constitutionally permissible conditions on states receiving federal funds.

Above all, a healing presidency will regard compromise not as a disagreeable necessity but as an opportunity to acknowledge the legitimacy of competing opinions, interests and principles in a large, pluralistic republic. Legal status for the “Dreamers” is important, and so is border security.