What, then, should we make of Sanders’s decision to embrace a nearly revolutionary label, “democratic socialism,” but define it in terms of American left-liberal politics?

One answer is that as someone who did live and work in left-wing and Marxist circles for much of his adult life, he wants to bring the term itself into the mainstream of American politics. To not just embrace the “socialist” attacks as a badge of honor but to make “democratic socialism” an extension of the New Deal is to make it sound normal, even desirable. More Americans may embrace the label. And because the term still implies a larger set of ideological commitments outside of Democratic Party liberalism, some of Sanders’s followers will become bona fide socialists who want that Debsian transformation of economic relations in the United States. It has already happened, in fact, with the substantial growth of the Democratic Socialists of America since 2016 and an increasing (albeit still small) number of Americans with a positive view of “socialism,” including a bare majority of the youngest adults.

The term does other political work. It distinguishes him from his rivals in the Democratic primary and suggests he wants to go further than his stated views — that he’s also interested in fundamental transformation, even if his program isn’t more meaningfully progressive than that of his closest ideological rival, Elizabeth Warren.

There’s another way to understand Sanders’s rhetoric around “democratic socialism.” For Harold Meyerson of The American Prospect , Sanders embodies the not-always-clear divide between liberals and the left. “In running as a democratic socialist who seeks to complete and update F.D.R.’s agenda,” he writes, “Sanders straddles the very fuzzy border between social democracy and American left liberalism.” In both traditions, democracy is an economic project as well as a political one. Perhaps Sanders is just trying to make that explicit — to once and for all marginalize the centrist Democratic Party politics of the past three decades, in which the economic rights of workers were subordinate to the demands of capital — as well as show Americans how good, effective governance can include left-wing politics. It is the political project of his entire career, from Burlington to the Capitol Building.

One last thought. At the beginning of his speech at George Washington, Sanders took note of the “growing movement toward oligarchy” in the United States and the world at large. He listed the leaders of several governments — Putin in Russia, Xi in China, Mohammed bin Salman in Saudi Arabia, Rodrigo Duterte in the Philippines, Jair Bolsonaro in Brazil and Viktor Orban in Hungry — that “meld corporatist economics with xenophobia and authoritarianism.” I think this analysis, which I’ve written about in the past, can also help us make sense of Sanders’s idiosyncratic use of “democratic socialism.”

In a 1977 essay for Dissent magazine, “Socialism and Liberalism: Articles of Conciliation?,” the socialist writer Irving Howe addressed the “tacit collaboration of right and left extremes in undermining the social and moral foundations of liberalism,” which he described as “a great intellectual scandal of the age.” Those critics failed, he wrote, “to consider what the consequences might be of their intemperate attacks upon liberalism.” To assault the foundations of liberal democracy, he added, “meant to bring into play social forces the intellectuals of both right and left could not foresee.”

In straddling the two sides of the left-wing divide — in tying “democratic socialism” to the legacy of the most important figure in American liberalism — Sanders might be modeling a kind of pragmatism. Not the colloquial “pragmatism” of do what works, but something from the American philosophical tradition, where the truth of the matter is in the doing, not the definitions. He calls himself a “democratic socialist,” others call themselves “liberals,” but in the United States they’re part of a common project, fighting on a united front.

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