Counterintuitively, the real message of the 2020 election is that the U.S. remains strong. Voters elected, electors voted, and the transfer of power proceeds apace. A perfect storm—a destructive pandemic, an economic maelstrom, a crisis in race relations, a bitter election campaign and, in the end, the effort of a defeated president to foment all the trouble he could—still couldn’t prevent the constitutional process from taking its course.

But strong as America remains, one cannot call our nation serene. Even as foreign adversaries consider how to exploit U.S. divisions, and allies wonder how the political shenanigans affect their security, it’s important to analyze calmly how far our domestic polarization will undermine the Biden administration’s ability to carry out its foreign-policy agenda.

Here there is cause for concern. The American foreign-policy consensus has grown thin. Hamiltonian and Wilsonian globalists believed that the end of the Cold War gave the U.S. a precious chance to promote a democratic, liberal and capitalist world order. Jeffersonian and Jacksonian nationalists saw the end of the Cold War as an opportunity for America to stop spending so much effort and money on visionary projects overseas and to start focusing more energy and effort on nation building at home. Over time, as ambitious foreign-policy initiatives fell short—from the war in Iraq to the effort to democratize China through economic integration—the nationalist case gained adherents.