There can, however, come a point at which the way a politician acts becomes an act, a revival of vaudeville, and a caricature discordant with the demands of the highest offices. Christie, appearing recently on a sports talk radio program, erupted like Vesuvius when asked about a New York sportswriter who had criticized Christie’s friend Rex Ryan, coach of the New York Jets:

“Idiot. The guy’s a complete idiot. Self-consumed, underpaid reporter. . . . The only reason he’s empowered is because we’re spending all this time this morning talking about Manish Mehta, who, by the way, I couldn’t pick out of a lineup, and no Jet fan really gives a damn about Manish Mehta.”

Mehta’s tabloid, the Daily News, filled a page with the words, “Who you calling an idiot, fatso!” Great fun. But who wants to call the person “Mr. President” who calls a sportswriter an “idiot”?

Americans want presidents to understand and connect with ordinary people, but not to be ordinary. Because presidents are incessantly on view in Americans’ living rooms, decorum is preferable to drama. Americans want presidential toughness, which Christie has demonstrated admirably in confrontations with government employees’ unions. But because he has demonstrated it abundantly, he does not need to advertise it gratuitously.