Murray Rothbard was arguably the leading anarchist theoretician of the second half of the twentieth century. The classical anarchist movement of the 19th and early 20th centuries included a number of prominent and innovative thinkers: Stirner, Proudhon, Bakunin, Kropotkin, Tucker, Tolstoy, Spooner, and others. Yet the revival of interest in anarchism during the uprisings of the 1960s and 1970s failed to produce many new thinkers of this stature. An exception is Noam Chomsky, but Chomsky is primarily a critic of U.S. foreign policy and neoliberalism who functions as a left-liberal, social-democratic fellow traveler of anarcho-syndicalism. He’s added very little to the actual anarchist canon. Another exception is Murray Bookchin, who attempted to fuse the insights of classical anarchism with the ideas of the New Left, particularly the ecology movement, and eventually abandoned anarchism in favor of a new philosophy he simply called “communalism.” So it was ultimately Bookchin’s rival Rothbard (the two men regrettably didn’t get along) who ended up creating the most innovative and comprehensive body of anarchist theory in the postwar/late 20th century era. Virtually all other “anarcho-libertarian” thinkers of the time mostly copied Rothbard’s system, occasionally adding some ideas of their own: Morris and Linda Tannehill, David Friedman, Sam Konkin, George Smith, Karl Hess, etc.
Strategy was always an issue of primary concern for Rothbard, and he always aligned himself with the anti-state forces of the moment, wherever they were. In the late 1960s, this was obviously the radical Left. It would have been insanity for anarchists to attempt an alliance with conservatives at the height of the Vietnam War, while the Cold War was still raging, and when virtually all right-wingers were cheering on police repression of the antiwar movement. Instead, the natural allies of libertarians for the moment were the antiwar protestors, student rebels, youth counterculture, the black power movement, and other popular radical strands of the time. Rothbard even participated in a coalition with Trotskyists and Maoists under the banner of the Peace and Freedom Party. These efforts worked remarkably well for a time, and the libertarian movement experienced much growth during the late 1960s and early 1970s, due in large part to an influx of countercultural radicals from the New Left.
However, by the early 1990s, two decades later, Rothbard realized that the radical Left of the 1960s had grown up and was in the process of taking power politically, and that the cultural radicalism of the 60s had already become a stagnant cliche that was just as often used as a force for conformity and repression as liberation. Meanwhile, the Cold War had ended and at least some right-wingers were rediscovering their isolationist roots. Hence, the birth of paleoism, and the planting of the seeds for eventual explosion of Ron Paulism 15-20 years later along with the corresponding growth in libertarianism generally.