Second, it is no longer mere wishful thinking that Trump either won’t serve out his term or won’t be on the ballot next year. Thursday’s BuzzFeed bombshell that the president directed Michael Cohen to lie to Congress may prove a dud, but there is no question the president’s legal jeopardy is increasing. A Republican who challenges him early could reap benefits in fund-raising and visibility, not to mention personal honor.

Most important, though, is the future of the G.O.P. itself. Every democracy is bound to have a party that represents society’s conservative instincts. The question is: What kind of conservatism? As Jerry Taylor of the Niskanen Center puts it, “The party deserves a choice about whether it wants to continue down the path of Le Pen-style blood-and-soil nationalism or return to its noble origins as the party of Lincoln.”

Larry Hogan isn’t the only Republican who understands the need for that choice. But he is one of the few who can offer a serious and meaningful alternative to the corroded conservatism we have in Washington today. Stepping forward now would mean stepping fully into his father’s shoes.