With the Democratic presidential primary now essentially a three-way race between Joe Biden and the two top progressives candidates, Senators Elizabeth Warren and Bernie Sanders, it seems inevitable that comparisons between the latter two will grow more frequent (and impassioned) as the campaign goes on. Up until now Warren and Sanders have been careful not to criticize each other directly, and at this point the smart thing for them to do would be to team up against Biden, who is lightyears away from both of them politically. Eventually, however, progressive voters will be forced to choose between two solid candidates who share much in common.

Though Sanders and Warren have had nothing but kind words for each other over the past six months, the same can't be said for a vocal minority of their supporters who have engaged in both dumb and disingenuous attacks. Some Sanders supporters have criticized Warren for being registered as a Republican a quarter-century ago (even though she mostly voted Democrat during her Republican years), while some Warren backers have recycled lazy and discredited "Bernie Bro" arguments from the 2016 primaries, basically claiming that people only support Sanders because he is a man (despite the fact that Sanders has more female than male supporters and one of the most diverse — and by far the youngest — bases).

There have also been efforts to inflate the differences between the two progressive candidates, whether it's leftists wielding Warren's "capitalist to my bones" quote to make her out as some kind of neoliberal centrist, or liberals criticizing Sanders for being soft on gun control when he has a D-minus rating from the NRA.

Of course, the opposite is also true. While some exaggerate their differences, others overstate their likeness, as if it is merely a choice between two different personalities with identical politics and interchangeable platforms. The political and philosophical differences between the two aren't quite as trivial as some make them out to be, and their worldviews do diverge in pretty significant ways that are worth exploring. Though both are genuine progressives, Warren and Sanders come from distinct political traditions that go back more than a century, and these traditions end up leading to very different assumptions about the fundamental problems in our society and how to address these problems.

Sanders clearly comes out of a socialist tradition, while Warren's worldview and political style springs from a more progressive populist tradition. Though the latter's comments on being a "capitalist" are somewhat overblown, they do reveal something important about the ideology underpinning her politics. For Warren, capitalism is the best system when it functions as it is supposed to — that is to say, when there are rules that ensure fair competition. "I believe in markets. What I don't believe in is theft, what I don't believe in is cheating," said Warren in an interview last year. "I love what markets can do... They are what make us rich, they are what create opportunity. But only fair markets, markets with rules. Markets without rules is about the rich take it all, it's about the powerful get all of it. And that's what's gone wrong in America."

In March, Warren expanded on her position, stating on CBS's Face the Nation that "it is not capitalism to have one giant that comes in and dominates," and that it's "just wrong" for people to call her a socialist. Though her somewhat idealized vision of capitalism is questionable, she is certainly correct not to call herself a socialist.

In the late 19th and early 20th century, American socialists and populists were both on the forefront of the struggle against the immense power of corporate monopolies, which had come to dominate the U.S. economy. Yet while socialists and populists were allied against the Rockefellers and Vanderbilts of the world, they ultimately saw the economic transformation of the previous 50 years from very different perspectives. The populist movement emerged in rural states across America in the 1880s and 1890s, and was essentially an agrarian revolt against the growing power of corporations and the erosion of the traditional agrarian economy. "The Populist fear," writes Lawrence Goodwyn in his classic study of the movement, was that "corporate concentration would undermine the popular autonomy necessary to the preservation of authentic democratic dialogue." In his influential book The Age of Reform, liberal historian Richard Hofstadter notes that an "agrarian myth" that pictured a land of small, self-sufficient "yeoman" farmers in the past was prevalent in the populist movement.

"The utopia of the Populists was in the past, not the future," observes Hofstadter. "The Populists looked backward with longing to the lost agrarian Eden, to the republican America of the early years of the nineteenth century in which there were few millionaires and, as they saw it, no beggars, when the laborer had excellent prospects and the farmer had abundance, when statesmen still responded to the mood of the people and there was no such thing as the money power."

Socialists saw the rise of monopolies and growing levels of inequality as a natural consequence of capitalism, and did not share the same kind of nostalgia. Industrialization and economic concentration were painful yet necessary trends in economic development, and the eventual goal was for workers to gain democratic control of the companies they worked for and to move beyond capitalism towards socialism. In other words, socialists looked single-mindedly to the future.

Populists and progressives didn't reject capitalism itself, but the extreme concentration of capital and the growing domination of a few massive corporations over economic and political life, which had ostensibly perverted the true nature of capitalism. Thus, antitrust laws and other regulatory measures were adopted to ensure "fair competition," and later, during the New Deal, further reforms were enacted to reduce extreme levels of inequality and mediate class tensions. Many progressives and New Dealers saw themselves as saviors of capitalism, and today, progressives like Warren and former labor secretary Robert Reich see their political project in a similar light.

Though Sanders is hardly a Marxist, he doesn't have the same faith in capitalism, and his decision to identify as a democratic socialist shows that he believes in moving beyond capitalism in the long run. Of course, both candidates have displayed a kind of nostalgia for the "golden age of capitalism" in the mid-20th century, when labor unions were strong, top marginal income tax rates were high, and inequality was at historic lows. The major difference seems to be that Warren looks back at this time as a period of rule-based capitalism functioning as it was supposed to, while Sanders looks back at this period as a time when America was slowly moving towards socialism after many years of class struggle, before a major capitalist backlash ensued.

How these different perspectives on capitalism translate into policy differences is subtle but noteworthy. Warren's plan to fight climate change, for example, demonstrates her faith in the private sector and the rule-based market, while Sanders' plan displays a fundamental distrust of the private sector to do what needs to be done to combat climate change. As Meagan Day (who openly supports Sanders) observed in Jacobin after last week's CNN town hall on climate change, Warren's solutions rest "heavily on plans to coax and regulate" the capitalist class "into leading the climate effort themselves," while Sanders wants to bring private utilities under public ownership and create millions of public sector jobs.

One of the clearest examples of Warren's approach to creating a fair capitalist economy is laid out in a bill she introduced last year that would establish a "co-determination" system commonly found in European countries like Germany. The bill, appropriately named the Accountable Capitalism Act, would obligate corporations with more than $1 billion in annual revenue to obtain a new federal charter that would require at least 40 percent of the board of directors to be selected by employees and instruct company directors to "consider the interests of all corporate stakeholders." "For most of our country's history," read the press release, "American corporations balanced their responsibilities to all of their stakeholders — employees, shareholders, communities — in corporate decisions. It worked: profits went up, productivity went up, wages went up, and America built a thriving middle class." As usual, Warren's view of the past — and of American corporations — seems to be tinted by rose-colored glasses.

In May, Jeff Stein reported in the Washington Post that the Sanders campaign was devising its own plan to transform American companies. Sanders, according to Stein, is "working on a plan to require large businesses to regularly contribute a portion of their stocks to a fund controlled by employees, which would pay out a regular dividend to the workers." This would potentially give employees more power in corporate governance as shareholders, but Sanders is reportedly also planning to include a measure similar to Warren's that would require corporations to give workers a share of seats on the board of directors (regardless of ownership).

Ultimately, Warren and Sanders would both be transformative presidents, and the fact that Wall Street elites hate them both is proof that either of them would be a good choice for progressives. If Wall Street bankers and corporate executives have to choose, however, there's no doubt that they'll go with Warren, especially if it means avoiding a Sanders presidency. "She's preferable for many reasons," said investment banker and former Obama adviser Robert Wolf in July. "She's been very clear that she believes in fair capitalism. And the idea of promoting socialism I don't think is a winning strategy if the goal is to beat President Trump."

With five months to go before the first primary vote, the best strategy for Sanders and Warren is to continue their tag team offensive against Joe Biden, but eventually, progressives will have to have a debate about whether the goal is to reform or replace capitalism. Warren and Sanders offer two different answers to this question.

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