Prior to 2016, a video of an avowed Marxist praising a Democratic candidate would have been fodder for attack ads.

But last week, senator and presidential candidate Bernie Sanders tweeted a video endorsement from Bhaskar Sunkara, the editor of the Marxist magazine Jacobin. In it, Sunkara casts the Sanders campaign as not just about 2020 but a broader campaign to remake America along socialistic lines.

“This is a project,” he says, “to remake America and American politics.”

There’s no doubt, between Sanders and superstar Rep. Alexandria Ocasio-Cortez, that socialism is having a moment. The Democratic Socialists of America went from having 8,500 members in fall 2016 to more than 50,000 members in fall 2018. The new socialist movement’s hub in Brooklyn has been the subject of glossy magazine features; its fans, denoted by a red rose emoji in their Twitter handles, are inescapable on the platform.

In this movement, Sunkara is something like a head convener or ideologue. He founded Jacobin in 2011, way before socialism was cool again, in an effort to repopularize the moribund American left. Today, it’s the leading left publication in the country, a place where socialists publish dispatches from across the world and debate proposals for a post-capitalist future.

In an attempt to take this left revival a step further, Sunkara has just published a new book, The Socialist Manifesto. The name makes the ambition of the slim 243-page volume plain: Sunkara’s aim is to write both a history of socialism and a blueprint for its future, a road map to guide activists looking to end capitalism and replace it with something other than Soviet-style communism. The book’s penultimate chapter, “How We Win,” is literally a 15-point plan for a democratic overthrow of American capitalism.

The book is a testament to the self-confidence of the new American socialist movement, a group certain of its rightness and uninterested in compromising on its radical ends. The ambition and excitement of the movement, and its youthful members (Bernie aside), pulses through this and most other new socialist texts.

Yet there is a specter haunting The Socialist Manifesto: the specter of liberalism.

The deep tension between left-liberalism, aimed at reforming capitalist liberal democracy, and socialism, aimed at overthrowing it entirely, has defined the politics of the left for well over a century. Sunkara’s book pores over details of this tension in the past, including debates between reformists and radicals in places ranging from 19th-century Germany to 20th-century America. But it is comparatively muted on the debate’s present and future.

This is a shame. The truth is that liberals, currently at their weakest and most defensive since the end of the Cold War, have a lot to learn from the energy and ideas of socialists like Sunkara. They don’t need to join the socialist movement, but they do need to treat it respectfully — and study what makes it so vital today.

Meanwhile, although socialists have found real success pressuring liberals from the outside, it’s not nearly enough to achieve their ambitious goals. If socialists want to actually help shape policy in the short term, they can’t just write manifestos and mean tweets. They need to form a broad political coalition to work with them on everything from union actions to battles over legislation in Congress.

Liberals and socialists today need each other, whether they like it or not. The question raised by the rise of the modern left is whether the fundamental intellectual tensions between left-liberalism and socialism, together with more than 100 years of historical conflict, can prevent the formation of a new popular front.

Why socialists need liberals

The Socialist Manifesto is an odd book.

It opens with a hypothetical chapter about an idyllic America transformed by a socialist party led by Bruce Springsteen, mostly told from the perspective of a worker at Jon Bon Jovi’s father’s curry pasta sauce bottling plant.

The bulk of what comes after that is not a manifesto at all. It’s mostly a recounting of the socialist movement and its offshoots, from Marx and Engels forward. Sunkara, to his credit, doesn’t shirk from examining the dark times of Stalin and Mao, even conceding that “we cannot claim that the excesses of Maoism had nothing to do with Marxism.”

However, the essential theme of the book is that Marx and the movements he inspired were largely right, and that the Soviet Union and Maoist China were authoritarian deviances from an ideology that is, at its core, democratic and liberatory. “Today there is much talk of ‘democratic socialism,’ and indeed I see that term as synonymous with ‘socialism,’” he writes.

So how does one revive American socialism in the 21st century — and prevent a rerun of the failures of the 20th?

Socialists need to start, Sunkara writes, by electing Bernie Sanders president, then quickly pass policies like Medicare-for-all that push the US toward a more centralized model of social democracy. Other goals include abolishing the Electoral College, rewriting the Constitution to allow for amendments by referenda, and replacing the House and Senate with a “proportionally elected unicameral legislature.”

But socialists need to go deeper than all that, in Sunkara’s view. “Democratic socialists must secure decisive majorities in legislatures while winning hegemony in the unions,” he writes. To do that, they create “a new generation of nonsectarian socialist organizers,” embed them in “working class” professions like education and health care, and create a new “workers’ party” that pushes Democrats to the left and eventually becomes “a completely independent, democratic socialist ballot line.” Only then, he believes, will it be possible to fully transition from capitalism to a bright socialist future.

Some of these objectives (electing Sanders) are more immediately plausible than others (getting rid of the House and Senate). On the whole, though, enacting this agenda is the work of a generation, if not multiple generations. Yet the problems Sunkara identifies as the motivation for socialism — he claims it can cure poverty, economic exploitation, climate catastrophe, and even nationalist wars — cannot wait decades.

The Affordable Care Act is still under attack, with millions standing to lose their health care. Major climate change action has to happen in the near future to prevent irreversible, devastating warming. The Trump administration is slouching toward war with Venezuela and Iran. Sunkara himself admits some response to this kind of immediate problem is necessary.

“It is possible to achieve certain socialist goals within capitalism,” he says. “Fighting climate change can’t wait until ‘after the revolution.’”

But how are socialists going to achieve those goals when the largest socialist movement in America, a country of 330 million people, is 50,000 strong? How do you fight the immediate battles while still waging the larger war?

The Socialist Manifesto doesn’t have much to say on this question. But there’s an obvious answer: Socialists need to find a way to work with the liberals who dominate the country’s major center-left party. For socialists to achieve their immediate goals, to stave off disaster and start moving the country in their direction, there’s no alternative to some kind of popular front with liberals in a series of immediate, practical fights. It’s not enough to push liberals to the left; you also need to help left-liberals beat the right and muscle broadly left-wing policy ideas through actual legislatures.

But can this alliance really happen?

The deep barriers to a liberal-socialist detente

The modern American left seems to treat “liberals” and “liberalism” as enemies rather than partners. Left Twitter personalities and publications are constantly denouncing the timidity and perfidy of liberals; the need to move “beyond liberalism” is a popular theme (that’s to say nothing of bromides against “neoliberalism,” a separate but oft-conflated beast).

Sunkara’s book is more restrained but still a bit cutting. The book never defines “liberals” or “liberalism” as terms, nor engages with their political tradition in any sustained way. But it’s lightly peppered with derisive references to them. Liberals are castigated for everything from failing to vigorously oppose World War I to watering down the Black Lives Matter movement; liberalism is described as “inadequate” to 19th-century German workers’ needs and decried for its “mendacity” in early-20th-century Russia.

Those good things accomplished under capitalism — the American and European welfare states, most notably — are credited to social democrats, presented as offshoots of the Marxist tradition. But social democracy is, at its core, a movement that marries socialist concerns about the misery caused by capitalism to liberal reformism. What is social democracy if not the left pole of liberalism?

As a liberal myself, I’m tempted to hit back even harder at Sunkara and the rest of modern left’s attacks on liberalism. The world’s most important Marxist states have all descended into authoritarianism, whereas the world’s freest and most egalitarian countries are all liberal democracies. Modern socialist intellectuals and publications — including Sunkara’s Jacobin — have celebrated Hugo Chávez, the late Venezuelan socialist leader whose policies dismantled the country’s democracy and destroyed its economy. The nightmare in Venezuela goes curiously unmentioned in The Socialist Manifesto.

But my impulse here is part of the problem: It’s not just socialists who have a tendency to take gratuitous shots at their natural allies. Punching left is a time-honored tradition among liberals, especially in relatively right-leaning America. It’s partly a way to signal “seriousness” to moderates and conservatives, but only partly. The liberal-socialist disagreement stems from deep-seated philosophical disagreements.

Liberals prioritize individual rights and formal democratic freedoms over economic equality, concerned that the socialist dream of “class warfare” is inimical to a society that depends on mutual cooperation and tolerance. Liberals focus on injustices that they believe undermine the foundational promises of this system, like racism and extreme economic inequality, rather than overturning the economic class system entirely.

Socialists believe that liberals are entranced by “bourgeois democracy,” blind to the ways private ownership of the means of production makes reform inadequate and meaningful democracy impossible. The liberal idea of democracy under capitalism is naive, they say, when inequality inevitably leads to the rich functionally purchasing control of the political system. Society is at its heart a negative-sum contest between classes, where the rising clout of capital invariably ends up hurting the poor and working class.

Obviously, these are stylized summaries of profoundly complicated political visions. But at their core, they speak to the ways that cooperative-minded liberals and conflict-minded socialists disagree — and why they see each other as so threatening.

Yet these big-picture disputes aren’t really relevant to the policy debates in America today, even the ones that split the Democratic party.

Medicare-for-all wouldn’t threaten capitalism, as Britain’s National Health Service shows. Raising the marginal income tax rate on top earners up to 70 percent, as AOC has proposed, is just a return to pre-Reagan levels. Even the Green New Deal, the most ambitious set of left-leaning policy proposals in recent history, wouldn’t shake American capitalism to its core.

Moderates and conservative Democrats, like former Vice President Joe Biden, oppose these ideas — but that’s hardly the orthodox liberal position today. Left-liberals like Sen. Elizabeth Warren, a self-described “capitalist,” are on board with these ideas or similar versions of them. Even less left-wing Democrats than Warren, like Sens. Kamala Harris and Cory Booker, have stated their support for some of them.

The bitter tone of the liberal-socialist divide has little do with policy. Outright socialization of the economy isn’t really on the agenda at the moment. Rather, it stems from decades of fighting over first principles, historical grievances, and fundamentally contradictory worldviews — a visceral set of disagreements that limit cooperation even when they share significant immediate political interests.

Why liberals need socialists

But why should liberals care about Sunkara’s book — or the critique from the socialist left at all — given their vast numerical superiority? Twitter isn’t real life, after all, and Biden is beating Sanders by a fairly wide margin in the most recent polls. Why shouldn’t liberals just dismiss Sunkara and his fellow travelers as gadflies?

Well, for one thing, it seems like some of the socialist critiques of mainstream liberalism have been proven right.

Socialists have long argued that the Democratic attempt to appease Republicans by pursuing redistributive ends through market means would neither win stable conservative support nor do nearly enough to tackle entrenched economic inequality in the United States. They were correct on both counts, for reasons best explained by center-left UC Berkeley economist Brad DeLong.

Left-liberals, DeLong concluded, need to give up on the dream of an alliance with the center right, and start building a new policy agenda that can accommodate political visions to its left. This isn’t to say that Democrats should all join the DSA or start deferring to socialists on all policy questions — liberals still tremendously outnumber socialists, after all.

Rather, Democrats ought to make a more social democratic vision their political center of gravity, becoming more comfortable with direct state intervention in the economy instead of ginning up complex market mechanisms for accomplishing left-wing ends. That means more ideas like Medicare-for-all and the Green New Deal, fewer like Obamacare and cap and trade.

Liberals also need to learn from socialists in another, less tangible way.

The truth is that liberalism today is boring. Its exponents tend to be older and its ideas stale, seemingly fighting the same Cold War battles 30 years past their expiration date. This is partly the result of Democratic policy and electoral failures — the 2016 election was a body blow to standard-issue Democratic liberalism — but also a result of its ideological success. Liberalism has so thoroughly defined the Democratic Party for so long that for many people, it’s difficult to get excited about it.

What’s more, liberal intellectuals have entered into a kind of defensive crouch. When faced with a resurgent right — Donald Trump in America and far-right parties in Europe — they tend to speak in generic bromides about the value of bloodless abstractions like the “liberal international order,” or wring their hands and wonder if the right has a point about immigration. Their work too often feels either staid or accommodationist, either mere rearguard defenses of a flawed status quo or worryingly willing to accommodate the raw racism and xenophobia at the heart of the resurgent right.

Socialists, by contrast, are full of energy and confidence. To read The Socialist Manifesto or any other major works of the modern left is to be immersed in a movement sure of its own moral worth, clear on what it believes in and willing to fight for it. Twitter seems filled with socialists not only because they’re disproportionately represented among the kinds of people who tweet, but also because they have a passion for their ideals that so many liberals today seem to lack.

This is what American liberals need to learn from. They need to not shun socialist intellectuals like Sunkara but study them. To learn how they fight for their ideas, and work out a vision of liberalism that feels like it’s worth fighting for. Something that doesn’t bend over backward to appease the right, and has bold and interesting answers for new problems like climate change, mass migration, and the threat that truly grotesque economic inequality poses to democracy.

Liberalism in general, and social democratic left-liberalism in particular, has the most impressive historical track record of any political ideology humans have invented. No other set of political ideas and structures has contributed more to the betterment of human lives, the improvement of human welfare. It’s time liberals start acting like it.