New Jersey Gov. Chris Christie in Orlando on Saturday. (John Raoux/Associated Press)

Paris was for all Americans, but especially for Republicans, a summons to seriousness that should have two immediate impacts on the Republican presidential contest. It should awaken the party’s nominating electorate from its reveries about treating the presidency as an entry-level job. And it should cause Republicans to take another look at Chris Christie, beginning with his speech in Florida the day after the Paris attacks.

Until now, many Republicans have been treating the nominating process as a mechanism for sending a message to Washington. The eruption of war in the capital of a NATO ally is a reminder that the nominating process will potentially send a commander in chief to Washington. This might, and should, hasten the eclipse of Carly Fiorina, Ben Carson and especially Donald Trump. His coarse, vulgar and nasty 95-minute effusion last week in Fort Dodge, Iowa, answered this question: When he begins to fade, will he draw upon a hitherto well-hidden capacity for graciousness, or will he become a caricature of his normal persona, which itself is a caricature of democracy’s most embarrassing possibilities?

Watch Trump on YouTube and consider his manner in light of his stupendously unconservative proposal, made one day earlier, for a federal police force. (It would conduct about 500,000 deportations a month to remove approximately 11.4 million illegal immigrants in two years). Then watch Christie on YouTube and pay particular attention to his affirmation of the foundational conservative belief in the indispensability, the sovereignty and the prerogatives of nationhood.

To the large extent that Trump’s appeal is his forceful persona, no candidate in the Republican field can match Christie’s combination of a prosecutor’s bearing and a governor’s executive temperament. In Florida, Christie sounded a new theme: “There are all too many people in academia and in global business that aren’t really interested in America as a nation-state anymore.”

A day after the Paris attacks, outside the theater that was targeted, a German musician, seated at a grand piano bearing the peace symbol cherished by people who thought the Cold War was not worth winning, played John Lennon’s saccharine “Imagine,” which includes this:

Imagine there’s no countries

It isn’t hard to do

Nothing to kill or die for . . .

Right. Just one big happy caliphate. Lennon, as bad a political thinker as he was a grammarian, never learned this: Countries, meaning nation-states, are, for all their shortcoming and dangers, indispensable for making self-government possible and secure.

Heightened security concerns might be Christie’s opportunity. The more disorderly the world becomes, the less luminous is the one credential that supposedly qualifies Hillary Clinton for the presidency. The credential is not her adequate but unremarkable eight-year Senate career. Rather, it is her four years as secretary of state. Recall the question Ronald Reagan posed to voters at the conclusion of his single debate with President Jimmy Carter a week before the 1980 election: Are you better off today than you were four years ago? The electorate’s answer was emphatic.

In a debate 10 months from now, the Republican nominee will ask a variant of Reagan’s question: Is America safer or more respected today, anywhere in the world, than it was when Clinton became secretary of state? Today, Republican voters need to ask themselves a question: Whom do they want onstage asking that question? It is beyond peculiar, it is political malpractice for Republicans to fritter away time and attention on candidates who, innocent of governing experience, cannot plausibly ask that question with properly devastating effect.

For an example of pluperfect unseriousness, consider this Trump claim, which is amazingly absurd even considering the source: “I got to know [Putin] very well because we were both on ‘60 Minutes,’ we were stablemates, and we did very well that night.” They were not in the same stable; they were not in the same greenroom; they were not on the same continent. Trump was in a “60 Minutes” segment taped in Manhattan; Putin was in another segment, taped eight time zones away in Moscow. Yet somehow Trump “got to know him very well.”

Every day that such errant nonsense sloshes through the Republican nominating contest is a day when the party’s claim to represent what the country craves — adult supervision — becomes less credible. Fortunately, sufficient days remain for Republicans to reshuffle the deck, to relegate Trump’s rampaging to the nation’s mental attic, and to recognize in Christie a serious political talent.

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