The love of liberty has nourished our nation since before its founding. Yet classical liberalism, which ought to provide common ground for left and right in the United States, is under attack today by prominent elements of both.

The discontents to which the vilifications of classical liberalism are a response are neither imaginary nor frivolous. But the vilifications obscure the means for reducing the discontents.

A number of well-known progressive politicians suppose that socialism provides the answers to the economic and social injustices with which they believe America is rife. They do not speak of “central planning” and “a command economy” — much less bandy about such terms as alienation, class struggle, and the proletariat’s eventual triumph over the bourgeoisie. But led by Sen. Bernie Sanders, who in 2016 made a decent run at wresting the Democratic presidential nomination from the establishment-anointed Hillary Clinton, and freshman Rep. Alexandria Ocasio-Cortez and her Green New Deal, the left has increasingly embraced socialist ideas. They want to direct the economy from Washington to correct the purported grievous misallocation of resources within the United States that stems, they believe, from the institutionalized privilege of white men. They also favor shifting authority from nations to international institutions to advance a global redistribution of wealth and power.

Meanwhile, noteworthy conservative intellectuals are keen to hitch their movement’s wagon to nationalism to combat what they perceive as the misrule of cosmopolitan elites who scorn local traditions and love of country. These conservatives generally shrug off nationalism’s long and stormy history; the variety of aspirations to which the planet’s diverse peoples have dedicated their collective lives; and the propensity to plunder, conquest, and empire frequently bound up with nations’ sense of their just deserts and appointed destiny. Paradoxically, nationalist conservatives downplay and sometimes despise the classically liberal traditions embodied in America’s founding documents, manners and morals, and political culture. Apparently misinformed about the flexibility that fortifies American constitutional government, they presume that tempering free trade, and opposing open borders and transnational government require the overthrow of classically liberal principles.

But is either socialism or nationalism an effective response to the challenges that confront liberal democracy in America? If taken seriously, do they require Americans to abandon liberal democracy? Or can the legitimate anxieties and objections of left and right be accommodated while remaining true to the principles of liberal democracy?

Thirty years ago this summer in The National Interest, a young State Department official set off a worldwide debate by arguing that the “unabashed victory of economic and political liberalism” in the practical realm encouraged the philosophical conclusion that liberal democracy was reasonable and just because it reflected the unchanging realities, and satisfied the essential requirements, of human nature. If the sensational claim at the heart of Francis Fukuyama’s “The End of History?” were correct, it would follow that all legitimate criticism of liberal democracy in America must be resolvable within the framework of liberal democracy.

With the Soviet Union, under the leadership of Mikhail Gorbachev, only the most prominent example of a wave of democratization sweeping the world in the 1970s and 1980s, observers of world affairs, Fukuyama wrote, “sense dimly that there is some larger process at work, a process that gives coherence and order to the daily headlines.” Notwithstanding the hedging question mark in his title, that larger process, Fukuyama indicated, was “the end of history as such: that is, the end point of mankind’s ideological evolution and the universalization of Western liberal democracy as the final form of human government.”

Fukuyama — three decades later the author of several important books of political analysis and a senior fellow at Stanford’s Freeman Spogli Institute for International Studies — could see perfectly well in the summer of 1989 that international conflict had not ended. And he did not suggest that soon all nations would be holding free and fair elections and protecting individual rights. Rather, he contended that “there are powerful reasons for believing that” liberalism in the large sense — the notion that human beings are by nature free and equal and that legitimate governments protect universal rights based on the consent of the governed — “is the ideal that will govern the material world in the long run.”