Carlo Allegri / Reuters

Inaugural addresses are, in part, catechisms. The new president signals that he’ll take the country in a new direction. But he casts that new direction as consistent with old and cherished national principles, from which the country has strayed, and to which it must return.

Since Woodrow Wilson, and certainly Franklin Roosevelt, part of the catechism has been America’s mission to defend freedom around the world. For close to a century, incoming presidents have called American power a blessing from God, which the United States must use to assist the cause of liberty in other lands.

But this Friday, Trump may not say that. No president-elect in modern American history has talked less about America’s obligations to the rest of humanity. When it comes to foreign policy, Trump has two primary rhetorical modes. The first is transactional: America is being ripped off by other nations, and must cut better deals. The second is civilizational: America is part of the Judeo-Christian West, which is threatened by “radical Islam.” The former defines the world as a struggle between America and its trading partners. The latter defines the world as a struggle between civilizations. Neither mode suggests that promoting freedom for peoples of all nationalities, races, and religions serves America’s interest. Both are fundamentally zero-sum.

Trump’s aversion to speaking in missionary terms about America’s role in the world helped win him the Republican nomination. His establishment GOP rivals like Marco Rubio and Jeb Bush vowed to mimic Ronald Reagan, extending the frontiers of American power in Eastern Europe and the Middle East, and ostensibly liberating millions along the way. Trump realized that many ordinary Republicans found that prospect unappealing. In the wake of Afghanistan and Iraq, they doubted that America’s imperial exertions benefitted them. And to the extent they felt any obligation to people overseas, it was more civilizational than ideological. George W. Bush often described Al Qaeda as a threat to freedom in the Muslim world. Trump realized that Republican voters were less worried that ISIS would snuff out Middle Eastern democracy than that it would snuff out Middle Eastern Christians.

All of which creates a dilemma for Democrats. Now that Trump has overthrown the missionary class in his own party, what do they do? Democratic foreign-policy elites differ somewhat from Republican ones. They worry more about “stupid wars” and dream more about creating international institutions that solve common global problems like climate change. But they still believe in preserving America’s imperial role—whether in the Baltics, the Persian Gulf, or the South China Sea—and believe that if America abandons it, the world will grow more dangerous and less free. If Barack Obama didn’t make that argument emphatically enough for some, Hillary Clinton appeared poised to do so in stronger terms.

It’s thus possible to imagine a scenario—one can already see it on Russia—in which Democratic leaders pick up the rhetorical mantle that Trump has dropped, and call on America to defend the frontiers of freedom against dictators like Putin. A Democratic presidential candidate in 2020 who spoke that way might even win over some of the Republican hawks who feel uncomfortable in Trump’s GOP (as Bill Clinton did after “neoconservatives” grew alienated from George H.W. Bush in 1992).

The problem with this scenario is that there’s a foreign-policy insurgency in the Democratic Party, too. Grassroots Republicans and grassroots Democrats differ. The former worry more about the world’s influence on America; the latter worry more about America’s influence on the world. Grassroots Republicans want the United States to limit its global burdens by acting more unilaterally. Grassroots Democrats want the United States to limit its global burdens by acting more multilaterally. But progressive Millenials—the people who powered Bernie Sanders’s campaign and will likely power the Democratic candidates to come—are, in their own way, as skeptical of presidential catechisms about spreading liberty as are the Republicans who elected Donald Trump.

Trump wants America to be a “normal country” like China, which focuses on its own economic and civilizational interests. Liberal Democrats want America to be a “normal country” like Sweden, which helps solve common problems, but without telling the rest of the world what to do. America remains the closest thing to an empire in today’s world. Yet in the age of Trump, its foreign-policy debate has taken a strikingly post-imperial turn.

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