LA JOLLA, Calif. — One of the weirdest aspects of this year's Democratic presidential campaign is that foreign policy, potentially one of President Trump's most vulnerable issues, has been nearly absent from the debate.

Trump is steering the country into a foolish trade war with China that has spooked the stock market, frightened farmers and fueled uncertainty among investors at home and abroad. Without any significant pushback from Democrats, his tariff-driven “America First” agenda is pushing us toward what could be a decades-long cycle of global retreat and economic decline.

Even Trump seems worried about his tariff zealotry, moving Tuesday to delay the latest round from September to December.

China appears to be a strategy-free zone for Trump, but so is most of the rest of the world: His North Korea policy, at bottom, is an often fawning pursuit of a nuclear-armed dictator; his Iran policy is an undeclared economic war that he hopes won’t have kinetic consequences; his key Middle East alliance is the no-questions-asked embrace of a Saudi crown prince who has been jilted even by the neighboring United Arab Emirates; he treats traditional allies such as Germany and France as disposable tissue paper.

Do these issues get discussed in the Democrats’ campaign stumps and televised debates? Not so much. Many Democrats seem scared of sounding like supporters of trade agreements, foreign military commitments or the dreaded evil of “globalization.” Inexplicably, they cede this international ground to Trump. For Democratic presidential rivals, domestic issues take up all the oxygen.

So here’s a modest proposal for Democratic candidates who want to distinguish themselves in what has too often been a lackluster and dispiriting campaign: Make foreign policy an issue. Summon the public not to more senseless wars in the Middle East but to the real global challenge that will define this century — the competition, hopefully peaceful, with a rising China.

The domestic issues that animate Democratic voters come into better focus when we see them as part of this call to combat China. We need better schools, a fairer economy and an inclusive, diverse, welcoming society — not just because these values are morally right but also because they help rebuild our democratic political system so that it works again and, yes, can compete with an autocratic and intolerant China.

Today’s Democrats need a little more of President John F. Kennedy’s call to arms, not on foreign battlefields but at home. We should “pay any price, bear any burden,” as JFK put it during his inaugural address, to make the country stronger internally. The heroes in this version of the new frontier are teachers, farmers, factory workers, tech innovators and even Wall Street bankers.

Trump’s reelection strategy is to inflame identity politics. A successful Democrat will figure out a way to bank those flames by uniting the country to meet a foreign challenge. This should be a “Sputnik moment.” China’s strengths should help us to see our own weaknesses.

At a conference here on the U.S.-China problem sponsored by the University of California at San Diego, there was a consensus about this connection between repairing our domestic politics and regaining coherence internationally. Two former national security advisers, Democrat Thomas E. Donilon and Republican Stephen Hadley, used almost identical language to explain how keeping pace with China begins by fixing domestic problems.

Why aren’t Trump’s anti-trade policies criticized more by Democrats or moderate Republicans? The most likely explanation is that politicians are frightened by angry voters in the wings of both parties. But polls suggest there’s still solid support for free trade and global engagement. People aren’t stupid. They know their futures depend on competing effectively against China in a global market.

One benefit for Democrats of injecting foreign policy into this campaign is that it’s a call to idealism. It evokes a cause that’s bigger than identity-group politics or selfish personal interest. Americans may be mistrustful of elites, but they also want to believe in something larger than themselves. That’s a yearning that Trump can’t answer. He is small-minded selfishness personified.

American internationalism is weak when it’s a project of the coastal elites. It’s powerful when it comes from the heartland. People forget that the architects of postwar American power were people such as President Harry Truman from Missouri, President Dwight Eisenhower from Kansas, Sen. Mike Mansfield from Montana and Sen. J. William Fulbright from Arkansas.

If Democrats stopped running scared on foreign policy, they would see that this is an issue that can unite the country and summon disaffected Americans to a test on which their future livelihoods depend, quite literally. The China challenge could be the best issue the Democrats have, if they would just start talking about it.

Twitter: @IgnatiusPost

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