What underlies the strategic thinking of both Barack Obama and Donald Trump—if it is strategic thinking—is the primacy of domestic over foreign affairs. In 2011, Obama rationalized his decision to wind down the surge of U.S. forces to Afghanistan not only by asserting that “the tide of war is receding” but by arguing that “it is time to focus on nation-building here at home.” And when Donald Trump rolled out his formal national security strategy in December, he argued similarly that past presidents “engaged in nation-building abroad while they failed to build up and replenish our nation at home.” Like Obama, he emphasized domestic prosperity before international security. In their very different ways, both men are “America First” presidents.

Connected to the praise of attending to matters at home are second thoughts about the American habit of promoting liberalization abroad. Indeed the Obama-Trump consensus doubts the very legitimacy of that project, asking not about the use of American power for a common political good but “What’s in it for us?” Trump is characteristically blunt: “We can no longer .  .  . enter into a one-sided deal where the United States gets nothing in return.” He said that “his instinct” told him to remove U.S. forces from Afghanistan; in acceding to the recommendations of his national security advisers to keep some troops there, Trump insisted that the mission was restricted to “killing terrorists” and excluded any “nation building.”