Fewer still would make such a tasteless comparison.

Previous presidents have appealed to Americans’ patriotism in wartime. In peacetime, President Kennedy’s 1961 inaugural entreaty — “Ask not what your country can do for you. Ask what you can do for your country.” — inspired an entire generation.

The Trumpian call to duty, however, is a particularly bold — even counterintuitive — choice for a president whose core message has always been that he can save anxious Americans from having to make tough choices, to adapt to economic changes or to face scary cultural shifts. His pledge to Make America Great Again has never been about helping move the nation into the future, but about easing it back into a more comforting past. In his capacity as Strong Leader, he has vowed to take care of everything, and it is all going to be “so easy.”

There is, in fact, no problem so big or so complex that Mr. Trump has not boasted of his ability to fix it quickly and painlessly. Repealing and replacing Obamacare with a better, cheaper system? Easy. Returning domestic manufacturing to its heyday? Easy. Lowering gas prices? Ending the drug problem? Dealing with China? Easy, easy and easy. Restoring cultural and economic security by erecting a big, beautiful border wall that Mexico will pay for? Piece. Of. Cake.

Of all Mr. Trump’s grandiose claims, his pledge to restore lost manufacturing jobs remains among the most heartbreaking. “Don’t move. Don’t sell your houses,” he soothed voters in the Rust Belt town of Youngstown, Ohio, in 2017. “They’re all coming back,” he promised of the jobs and prosperity.

These dreams have not come to pass.

Mr. Trump’s rosy reassurances that trade wars “are good, and easy to win” have proved equally hollow. Farmers are not the only ones suffering. Manufacturers are paying higher prices. The instability is disrupting markets. Small wonder the latest Quinnipiac poll shows only 39 percent of Americans approve of the president’s trade policies.

It’s always possible that the president will confound the naysayers and emerge from what he has called his “little squabble with China” with some big-picture successes. Alternatively, this folly could wind up wreaking global havoc well beyond the economic sphere.

Either way, Team Trump recognizes the immediate political potential of its new messaging. The president’s gift for waging culture war has served him well in keeping his fans riled up and his critics off-kilter. By turning trade into a matter of national pride — a clash of civilizations, if you will — he’s reminding supporters that he is fighting for them against both foreign competitors and “globalists” here at home. This can help distract from whatever economic pain they’re experiencing. At least for now.