Kevin Lamarque / Reuters

The left-wing critique of the Obama years goes something like this: Swept into office with an immense popular mandate after President George W. Bush crashed the American economy, President Barack Obama pursued half measures that led to a slow, brutal recovery, setting the stage for the rise of Donald Trump.

To follow the logic of this critique, the next Democratic president would have to be someone willing to pursue broad reforms to the economy and health care, someone like Senator Bernie Sanders of Vermont, or Elizabeth Warren of Massachusetts. Sanders’s unexpectedly strong showing against Obama’s heir apparent, Hillary Clinton, in the 2016 Democratic primary, and Clinton’s subsequent defeat in the general election, was taken as proof that Americans were fed up with the failures of neoliberalism.

Given the strength of this left-wing policy critique, and the affection for Sanders’s ideas among Democratic voters, it may seem puzzling that Obama’s vice president, Joe Biden, now looks poised to secure the nomination. But the caution of the Obama era can be interpreted in two ways. One is the Sanders argument, that wide-reaching changes are necessary, and nothing less is acceptable. The other is that in a country where Obama’s moderate approach sparked a furious counterrevolution that threatens the foundations of the republic, the guy who is promising wealthy Democrats that “nothing will fundamentally change” might be a safer bet to make Trump a one-term president.

The left’s policy critique of Obama has real merit. The stimulus bill prevented a depression, but it was too small. The Affordable Care Act extended health insurance to millions of people, but left millions of others uncovered or undercovered. The Obama administration’s response to the housing crisis was a disaster that prioritized the stabilization of financial firms over keeping Americans in their homes. Obama established a new agency to regulate Wall Street, but was far too deferential to the financial institutions responsible for the 2008 recession. Unaddressed, these lingering issues helped Trump harness anger at the system and direct it at politically weaker targets: Immigrants, Muslims, and black Americans.

Some of these arguments ignore or understate the institutional and political constraints Obama faced. The administration’s housing-stabilization program was a calamity of its own making, but no public option for health care could have earned the votes of Senate moderates at the time, who were likewise spooked by the size of the stimulus. Chief Justice John Roberts’s entirely arbitrary decision to kneecap the Medicaid expansion left millions of the most vulnerable people in the country without coverage. Obama’s failures could not have led to the rise of Trump absent the racist ideological lens that made Trump’s appeals persuasive, which is why black and Latino voters, who were deeply hurt by the recession and slow recovery, were largely immune to them.

For the left, though, the 2020 Democratic primary was an opportunity to test its theory of politics. Sanders emerged as a strong early contender, promising a political revolution, a wave of new young and working-class voters, and a universal health-care system. Warren entered the 2020 race promising a similarly sweeping set of reforms, but struggled to win converts from the Sanders camp, was dismissed as too far left by the party’s moderate wing, and faced the proxy sexism of some primary voters assuming a woman was unelectable. Ultimately Joe Biden emerged as Sanders’s main rival, running on a liberal but not leftist platform, vowing a restoration of the pre-Trump era. Despite a confusing result in Iowa, Sanders won handily in New Hampshire and Nevada and looked as though he might even prevail in a divided field in South Carolina.

Then things went, well, south. First the Democratic establishment coalesced around Biden through a series of key endorsements, and then Democratic voters did, too. The blue-collar, rural white Democrats who backed Clinton against Obama, and then Sanders against Clinton, rushed to Biden this time. What some leftists interpreted as a rising white working class responding to a class-focused agenda in hindsight looks more like conservative Democrats using race and gender as proxies for how left-wing a candidate actually is. The promised surge of young voters for Sanders did not materialize.

The generation gap between Biden’s and Sanders’s supporters remains the most striking demographic distinction in the primary, and I believe it must be understood as not simply a question of ideology, but also fear of counterrevolution. Left-leaning American voters under 40 came to political consciousness during a calamitous Republican administration that led to endless war, economic collapse, and the destruction of a major American city, as well as the subsequent failure of competent, technocratic governance to fully ameliorate those disasters. Older Democrats witnessed decades of conservative ideological dominance of both parties, one that began with a nationwide white backlash to extending the promise of American democracy to all of its citizens.

It is understandable then, that younger voters today are more jaundiced toward compromise than their elders. It is also understandable that older voters, whose memories of counterrevolutions past motivate them to end the Trump presidency before the racial backlash it represents can be measured in decades rather than years, would choose a candidate they believe is best equipped to do so even if he does not precisely share their views. You could argue that the former are hopelessly naive, or that the latter are crippled by fear, but both are acting rationally, given their lessons of their own experiences.

Biden and Sanders each assembled cross-class, cross-racial coalitions, but Biden’s advantages with older black voters—the constituency most familiar with the danger and ferocity of American counterrevolution—gave him the edge. This happened despite the fact that most Democrats, including those in many states where Biden swept Sanders, support a government-run health-care system, Sanders’s signature policy proposal. Biden now possesses a commanding lead in delegates, given the remaining contests, and it is unlikely that Sanders can overtake him.

The Republican Party is not the Democratic Party. The GOP remains overwhelmingly white and Christian. Its homogeneous composition and winner-take-all primary structure left it vulnerable to takeover by a demagogue running on escalating denunciations of out-groups. With no internal constituency for which racial and religious bigotry against minorities was an existential question, Trump paid no political cost within the party for his overt prejudice, and none of his rivals were willing to outbid his promises to use the power of the state against those his base had grown to hate and fear. And, perhaps unsurprisingly, once in office Trump proved more successful at corrupting the executive branch than he has at advancing conservative legislation.

The Democratic Party’s culturally and ideologically heterodox composition, and its proportionate-allocation system, means that any one faction will struggle to dominate the others. The coalitional nature of the Democratic Party makes for less ideological discipline, but it also cultivates qualities necessary for multiracial democracy: tolerance, empathy, and the willingness to share power with those who are different from you. Without those qualities, political parties descend into authoritarianism.

Democratic voters appear to have settled on Biden. This means that the Democratic Party’s likely standard-bearer will be a man who has played a supporting role in every catastrophic mistake the party has made for the past half century. Biden is an architect of mass incarceration, a supporter of Bush’s disastrous invasion of Iraq, and one of the key legislators behind the bankruptcy bill that has contributed mightily to America’s debt crisis. Yet Biden can be moved. The former vice president has always instinctively placed himself in the center of the Democratic Party—to the right of the liberals and to the left of the centrists—for better and for worse. The party has moved left, growing more skeptical of war, the carceral state, and Wall Street, and Biden’s platform has moved with it.

Establishment Democrats believe that by preventing a self-identified democratic socialist from winning the nomination, they are in the best possible position to win back the White House from Trump. But Biden’s decades in public life not only provide the opposition with plenty of vulnerabilities to exploit, they suggest that even if he prevails, he could cripple his own presidency with an instinct to accept half a loaf on principle without even negotiating for the whole.

The failures of this approach, so popular with Democrats of Biden’s generation, are already on display with the COVID-19 pandemic. House Democrats passed a paid-sick-leave bill designed to cushion workers from the inevitable economic shocks that will result from consumers avoiding public places. In order to obtain Republican support, they included exemptions so large, they swallow the entire bill, leaving 80 percent of workers, mostly from big companies, without paid sick leave. House Speaker Nancy Pelosi defended the exemptions, saying she doesn’t “support U.S. taxpayer money subsidizing corporations to provide benefits to workers that they should already be providing.”

This is a ludicrous response; Pelosi might as well call for the abolition of Social Security on the grounds that corporations should be providing more generous pensions. If the Democratic Party cannot argue—even in the midst of an international crisis—that the state should provide for people who will otherwise be abandoned, it might as well be the Republican Party. The challenges the coronavirus poses to American economic and health infrastructure will require more competent leadership than the sycophantic, corrupt cult of personality occupying the White House is able to provide, and bolder thinking than the current Democratic leadership is apparently capable of.

Democratic centrists read the internal politics of their party far better than the left did. But getting the politics right is not the same as getting the policy right, and the Democratic establishment ignores the forces that contributed to Sanders’s rise at its peril. Even now, the robust economic recovery hides a vast affordability crisis. The Affordable Care Act really was not sufficient to fix America’s broken health-care system. The concentration of economic gains at the top really does threaten Americans’ livelihoods—but also democracy itself. The student-loan crisis really is suffocating an entire generation with debt. The inaugural conflict in America’s forever war, the war in Afghanistan, is old enough to vote. Although simply restoring the status quo ante might be a persuasive political argument to a majority of Democrats and perhaps even a majority of Americans, governing from that assumption would leave the country vulnerable to another takeover by an authoritarian demagogue, just as it was in November 2016.

Democrats may believe that they dodged a bullet by avoiding a Sanders nomination. But they should understand that Biden is just as much a roll of the dice.

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