Gregg Opelka:

It’s time for Donald Trump to tell himself the words he’s most famous for: “You’re fired!”

Amid speculation of a 2024 run and talk of a Grover Cleveland replay, there’s an inescapable drawback looming over a third Trump bid for the White House: obsolescence. Without meaning to, Mr. Trump has proved himself expendable.

Mr. Trump’s candidacy and presidency were, ironically, his 15th season of “The Apprentice.” Intentionally or not, he educated young Republicans in countering Democrats and resisting a predominantly hostile media. Contrast Mr. Trump’s pugnacious 2016 run with the weak-kneed timidity of the McCain and Romney campaigns. It is no wonder a new generation of Republicans found the experience novel and instructive. Unwittingly, Mr. Trump himself became the most persuasive argument for his stepping aside.

You don’t have to be Elizabeth Barrett Browning to count the ways another shot at the White House would be bad for Mr. Trump. His brand will be irreparably damaged if he suffers another loss. He will always claim the 2020 election was stolen and forever maintain his status as a winner. But should he be defeated in the 2024 general election (or, even more embarrassingly, the primary), he can’t cry foul again. Nobody likes a sore loser—especially a two-time loser.

It is much wiser for Mr. Trump to play the role of kingmaker. He can throw his bombastic support behind a younger candidate who shares his Republican bona fides with little risk to himself. Florida Gov. Ron DeSantis is an obvious choice. In 2024, assuming he is re-elected this November, Mr. DeSantis will have six years of political seasoning since his election in 2018.

He is far more palatable than Mr. Trump and unencumbered by the former president’s rough edges, mean tweets and pettiness. Yet Mr. DeSantis has the fortitude to endure harsh criticism without caving in, as his management of the pandemic and the “Don’t Say Gay” controversy demonstrate.

It is hard to think of a more suitable apprentice for Mr. Trump. But there are other capable 2024 flag-bearers, among them Nikki Haley, Gov. Kristi Noem and Mike Pompeo, all consonant with Mr. Trump’s political beliefs but still independent thinkers. Any would be a worthy successor but not a slavish clone.Mr. Trump can win a second term without putting his name on the ballot. No matter which successor gets the nod, it’s time for Mr. Trump to step aside and tell that person, “You’re hired!”

• US politics