On the libertarian side of the Republican coalition, the situation is even more depressing: Republicans such as former Texas Governor Rick Perry, who once offered important support for criminal-justice reform, are lined up behind the atavistic drug-war policies of the president and Attorney General Jeff Sessions, whose big idea on opiate abuse is more death sentences for drug traffickers. Deficits are moving in the wrong direction. And, in spite of the best hopes of the “America First” gang, Trump’s foreign policy has not moved in the direction of Rand Paul’s mild non-interventionism or the more uncompromising non-interventionism of his father, Ron Paul. Instead, the current GOP foreign-policy position combines the self-assured assertiveness of the George W. Bush administration (and many familiar faces and mustaches from that administration) with the indiscipline and amateurism characteristic of Trump.

Some libertarian moment.

Postwar conservatism, under the intellectual leadership of Buckley, Frank Meyer, and their allies, was, famously, a “fusion”—an alliance between social and religious traditionalists, anti-Communists and national-security hawks, and libertarians ranging from ideologues and idealists such as Henry Hazlitt and Ludwig von Mises to Chamber of Commerce types with their more prosaic concerns about taxes and regulation. The libertarians have always been a junior partner in that alliance, but for many years they punched above their weight. Partly that is because libertarianism is an intellectual tendency rather than a cultural instinct, one that benefited from the rigor and prestige of the economists who have long been its most effective advocates. And libertarianism has benefited from the fact that American elites are notably more libertarian in their views than is the median American voter. That dynamic was explored by the economist Bryan Caplan under a typically bold title (“Why Is Democracy Tolerable?”) with a typically needling conclusion: “Democracies listen to the relatively libertarian rich far more than they listen to the absolutely statist non-rich … Democracy as we know it is bad enough. Democracy that really listened to all the people would be an authoritarian nightmare.”

But if libertarianism benefited from its rich friends, it surely benefited even more from its impoverished rivals: the Soviet Union, Castro’s Cuba, North Korea, Mao’s China, and other practitioners of robust étatism. Despite the best hopes of the postwar conservative fusionists, libertarianism has always been more effective in opposition than in government. President Reagan may have called himself a libertarian from time to time, but he also enacted protectionist tariffs, radically expanded the military and the federal police powers, and failed to exhibit a great deal of energy in resisting the deficit-swelling spending bills sent to his desk by Tip O’Neill. The libertarian tendency mainly provided a useful ideological foil, not only to the totalitarian socialist projects of the time but also to more liberal efforts to expand the welfare states in the Western democracies. If you are not moving in the direction of Milton Friedman, the argument went, then you are moving in the direction of Leonid Brezhnev—it’s Chairman Greenspan or Chairman Mao.