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All four of my grandparents were sent to prison for their socialist convictions at some point in the 1920s or 1930s. When I was growing up in Europe, democratic countries from France to Italy were ruled by self-declared socialists. As a young activist in the Jusos, the youth organization of Germany’s Social Democratic Party, I sang along wholeheartedly when my comrades would intone “The Internationale” at the end of rallies, rounding off each rendition with a loud shout of “Long live socialism and liberty!”

Given my background, I am baffled by both the fear and the fascination that the socialist label now evokes in the United States. To someone who has grown up in a democracy that provides its citizens with universal health care and (virtually) free higher education, the idea that such policies are dangerously “socialist” is at best question-begging, and the insinuation that they somehow impinge on human liberty is simply bizarre.

But the great differences among the movements and countries that have historically called themselves socialist also makes me skeptical about leftists who think that embracing this label is enough to explain what kind of future they want. Some members of the Democratic Socialists of America, for example, simply want to emulate the rich democracies that provide their citizens with a generous welfare state. But others seek to “abolish capitalism” or sing the praises of the Venezuelan dictatorship.

Anybody who has studied the history of Europe—or, for that matter, Latin America—should know that some socialists crafted systems that left virtually no space to private enterprise and crushed the political freedoms of dissenters, while others combined government benefits with a robust market economy and the rule of law. What mattered was not whether a party or movement called itself socialist, but whether it recognized the danger of autocracy, and carefully formulated limiting principles that would stop it from going down the same path as the Soviet Union. So activists who hope to mainstream socialism in American politics must, at the very least, make clear what, exactly, they mean by the term.

This is why I was very hopeful when Senator Bernie Sanders’s campaign announced that the candidate would hold a major speech on “How Democratic Socialism Is the Only Way to Defeat Oligarchy and Authoritarianism.” After years of using the term about as imprecisely as many of his followers, I hoped that Sanders would finally set out why it holds such importance to him, what role the market would play in the socialist system he promises to build, and how he can protect his political project against the Soviet risk.

I can’t say he met my expectations.

In the most poignant passages of his speech, Sanders rightly argued that a robust welfare state need not be in tension with personal liberty. On the contrary, access to basic social and economic goods is a precondition for being able to make real choices:

Are you truly free if you are unable to go to a doctor when you are sick, or face financial bankruptcy when you leave the hospital?

Are you truly free if you cannot afford the prescription drug you need to stay alive?

Are you truly free when you spend half of your limited income on housing, and are forced to borrow money from a payday lender at 200 percent interest rates?

Are you truly free if you are 70 years old and forced to work because you lack a pension or enough money to retire?

This is a classic leftist critique of unbridled capitalism, and it retains much of the force it had back in the days of Karl Marx. Sanders made a strong case for the universal provision of affordable health care, the regulation of the financial industry, and generous old-age pensions. But he didn’t acknowledge—in this section or elsewhere—the ways in which the suppression of free markets has repeatedly fostered a different kind of oppression over the past century.

Virtually all socialist movements have claimed to embrace democracy, as Sanders did with a perfunctory reference to the Bill of Rights. What separated, say, the Sandinistas in Nicaragua, who ended up crushing political opponents, from the French Socialists, who respected the right to dissent, was in good part their attitude toward markets. Socialists who nationalized large parts of the economy, and severely restricted the functioning of the market, crushed freedom in two ways: First, they made it impossible for citizens to engage in private economic initiative. And second, they quickly started to abuse the power to take away the livelihood of political opponents.

This history makes it all the more important for Sanders to be clear on the kind of role that he envisages for the market in the society he is setting out to create. What forms of private economic initiative would be allowed? After sitting through his 40-minute speech, I was none the wiser about this basic question. Instead of clearing, Sanders’s long-standing ambiguity about the nature of the socialism for which he stands settled over me like a sea of fog.

If Sanders was coy about the details of a “socialist” economy, he was downright disdainful of the notion that a speech on socialism and authoritarianism should seriously grapple with the long history of socialist movements that have ended in dictatorship. In his view, the threat of autocracy comes exclusively from the right. Just as in the 1930s, “America and the world are once again moving towards authoritarianism.” This danger is driven by “right-wing forces of oligarchy, corporatism, nationalism, racism, and xenophobia.” The only answer that will stave off fascism is, you guessed it, “democratic socialism.”

Thus Sanders name-checked Adolf Hitler and Benito Mussolini but remained silent about Joseph Stalin and Mao Zedong. And while he rightly decried the autocratic tendencies of Russia’s Vladimir Putin, China’s Xi Jinping, Saudi Arabia’s Mohammed bin Salman, the Philippines’ Rodrigo Duterte, Brazil’s Jair Bolsonaro, and Hungary’s Viktor Orbán, he neglected to mention leftist autocrats such as Venezuela’s Nicolás Maduro, Cuba’s Raúl Castro, Nicaragua’s Daniel Ortega, Zimbabwe’s Emmerson Mnangagwa, or North Korea’s Kim Jung Un. Indeed, the only connection between socialism and autocracy that Sanders was willing to acknowledge is the one that exists in the feverish imagination of the ignorant right: He decried the “red-baiting” in which Republicans have long engaged.

The implication was obvious. Anybody who was hoping for a clear account of the differences between Sanders’s political ambitions and those of autocratic socialist regimes is a fellow traveler of Richard Nixon, Newt Gingrich, John Boehner, Donald Trump, and the Heritage Foundation.

Over the past few months, Senator Elizabeth Warren has issued a series of ambitious proposals for economic reform. Under her plans, the tax system of the United States would become a lot more redistributive. Americans would enjoy far more generous entitlements. Every resident would be guaranteed access to affordable health care. And the state would become much more active in curbing the formation of monopolies.

But Warren has argued that she is seeking to rescue, rather than bury, capitalism. (She cleverly dubbed one of her most ambitious plans the “Accountable Capitalism Act.”) And she has clearly articulated that the market has an important role to play in the country she hopes to build. In fact, many of her proposals are as much about ensuring that there is true competition in areas like tech as they are about restricting the operation of free markets.

In this regard, Warren is the heir of some of the most successful left-wing movements of the 20th century. Whether they called themselves socialists, social democrats, or progressives, figures such as Germany’s Willy Brandt, Britain’s Clement Attlee, and America’s Franklin Delano Roosevelt were clear about the benefits of markets and forthright about the dangers of left-wing authoritarianism.

Even in the United States, where the horrors of the gulags and the indiscriminate killings of Pol Pot have always felt rather remote, the most eloquent democratic socialists have taken this crucial lesson to heart. For thinkers like Michael Walzer, the label “Democratic Socialist” entailed a deep recognition that the left could be just as vulnerable to autocratic temptation as the right.

A serious speech about socialism and authoritarianism would have built on the political legacy of Brandt and the philosophical legacy of Walzer. The speech Sanders gave was not serious.

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