Donald Trump’s supporters want an American Caesar. Back in 2016, Paul LePage, then governor of Maine, made it explicit. “We need a Donald Trump to show some authoritarian power in our country,” he declared. Joe Sitt, a major player in New York real estate and an early Trump backer, chipped in: “We don’t have a president, we have a king.” Five years later, January 6 and its aftermath crystalized another reality: Trump found fair and free elections useless. He and his allies had grown weary of democracy. After all, they had lost. The Republican party had a new credo: “Heads,...