A massive crowd assembled on the National Mall during the March on Washington.Robert W. Kelley / The LIFE Picture Collection / Getty

The 1960s have achieved almost mythic status as a hinge point in American history. Both those who welcomed and those who feared the convulsive changes the decade brought can agree on one thing: Socially, culturally, and politically, the nation was a very different place when the ’60s ended than when they began.

This could be another such moment.

The ’60s watershed moments—the civil-rights campaigns in Birmingham and Selma, Alabama; Martin Luther King Jr.’s March on Washington and the anti-war March on the Pentagon; the outpouring of demonstrations following the shootings at Kent State—can seem in retrospect like towering peaks of transformative activism far beyond any contemporary experience. But history may look back on this period as a comparable transition in the nation’s politics and culture, driven primarily by the largest generation of young Americans since the Baby Boomers who flooded the streets decades ago.

Enormous differences separate the two periods. But they may ultimately prove united by the magnitude of the change they impose.

The 1960s saw the emergence of social movements around civil rights, opposition to the Vietnam War, feminism, Mexican American activism, and environmentalism, as well as the first stirrings of gay rights. The past decade has seen youth-led movements around climate change, gun control, immigration, and inequities of gender (#MeToo) and race (Black Lives Matter).

Seen as one long wave of change, modern activism “has the sweep of the ’60s,” says Todd Gitlin, a historian (and veteran) of those protest movements and a sociologist at Columbia University. And just as the 1960s triggered big changes in American attitudes on issues from premarital sex to trust in authority, the past few years have also witnessed big shifts toward greater support for gay rights; more agreement that human activities are causing climate change; and recognition that systemic racism remains embedded in American life, a consensus that has rapidly solidified since the death of George Floyd in Minneapolis. Young people have been at the forefront of each of these changes.

Today’s long wave of protest shares one other quality with its predecessor: It has changed popular culture and the contours of public opinion more quickly than it has public policy or the nation’s electoral landscape. Now, as then, an electoral system that favors older generations—through structural imbalances that favor rural states with older and less diverse voters—is responding slowly to calls for change from younger Americans.

And yet, just as with the Baby Boomers before them, Millennials, Gen Z, and the generation following them will eventually define the new American mainstream through their priorities and viewpoints, as over time they become a majority of the nation’s population. In that way, the huge number of people on the streets of America’s major cities this month may offer a preview of how profoundly these younger generations may reshape the country’s politics once they vote in numbers that more closely approximate their growing presence in the population overall. “This transition is inevitable,” says Ben Wessel, the executive director of NextGen America, a group that organizes young people for progressive causes. “The question is: How quickly is it going to get here?”

The differences between Baby Boomers and today’s young people are easy enough to see. Younger generations now are far more diverse: White people made up four-fifths of the Baby Boom (defined as those born between 1946 and 1964), but represent only three-fifths of Millennials (born 1981 through 1996) and only a little more than half of Gen Z (tentatively defined as those born from 1997 through 2014).

Allen Matusow, the author of The Unraveling of America, a seminal history of the country during the 1960s, noted another key difference in an email: Back then, many of the protests grew out of an assumption of abundance after two decades of the nation’s post–World War II boom; young people today face more precarious prospects. While the white, college-attending component of the ’60s generation “assumed unending growth, abundant consumption, and good jobs when they were ready to take them,” young people now face “environmental degradation, rising sea level, [and] concentrations of wealth that threaten democracy,” among other challenges, said Matusow, who is also a fellow at the Baker Institute of Public Policy at Rice University. Put another way: One movement was a revolution of rising expectations; the other is a struggle to gain a foothold.

And while the great social movements of the 1960s and early 1970s had clearly identified leaders who became iconic figures—King and Malcolm X for civil rights; Abbie Hoffman, Jerry Rubin, and Tom Hayden for the anti-war and student movements; Cesar Chavez for farmworkers; Betty Friedan and Gloria Steinem for the feminist movement—today’s activism is largely leaderless, notes Kirsten John Foy, the founder of the Brooklyn-based activist group The Arc of Justice. Particularly within the Black Lives Matter network and the broader uprising against discriminatory policing, Foy says, “We have moved beyond this messianic notion of leadership, even in the black community. It has democratized the movement and it has reenergized the movement.”

In both decades, the fulcrum of change was the emergence of a vast new generation determined to question the rules and priorities that it inherited. Young people were hardly the only voices agitating for change during the 1960s, just as they are not the sole source of activism now. But in each case, the sheer bulk of the rising generation provided a critical mass for social movements.

At its peak in 1964, members of the Baby Boom represented 37 percent of America’s total population, according to Census figures provided by the demographer William Frey. Frey calculates that, at their peak in 2015, Millennials constituted a little less than one-fourth of the population. But Frey projects that, combined, Millennials and Gen Z will exceed two-fifths of the population from 2013 to 2035. They’ll fall only to slightly below that level through 2050. (Surprisingly, there were about 11 million more births during the Gen Z years than during the Millennial years.)

In the ’60s, the huge pool of baby boomers receptive to change provided the infantry for the succession of protest movements. “The rise of organized movements among previously marginalized groups was indeed contagious in these years,” wrote the historian James T. Patterson in Grand Expectations, his sweeping history of America in the first decades after World War II. The visibility and impact of the early movements—those in support of civil rights and against the war—encouraged the development of those that came later: for environmental protection and rights for women, Chicanos and farmworkers, and, finally, the gay community. Each helped clear the path for the next.

Although today’s social movements have largely been viewed as independent, even isolated, efforts, a similar progression is visible over roughly the past decade.

  • The Black Lives Matter movement coalesced in 2013 after George Zimmerman was acquitted for shooting the African American teenager Trayvon Martin, and the movement took a huge leap forward in public consciousness following the fatal police shooting of Michael Brown in Ferguson, Missouri, in 2014.
  • Young people brought to the country illegally by their parents—the so-called Dreamers—have kept up a steady drumbeat of protest throughout the decade to achieve, and then protect, their legal status.
  • The women’s marches against Donald Trump’s administration in January 2017 brought out massive crowds in cities across the country.
  • The #MeToo movement that grew rapidly in fall 2017 after exposés on the sexual-harassment and assault allegations against Harvey Weinstein and other powerful men has forced sweeping changes in Hollywood, the restaurant and fashion industries, and other institutions.
  • Students who survived the mass shooting at Marjory Stoneman Douglas High School in Parkland, Florida, organized mass marches for gun control in Washington, D.C., and hundreds of other cities in March 2018.
  • Protesters likewise turned out that June in Washington and cities across the country to oppose Trump’s family-separation policy at the southern border.

The massive nationwide demonstrations since Floyd’s death in Minneapolis have provided a kind of culmination for these disparate strands of activism. The protests have been notable for the racial diversity of their crowds. A poll released Thursday by the nonpartisan Kaiser Family Foundation found that while young people ages 18 to 29 account for 52 percent of all adults who have protested—more than double their share of the overall population—participants closely tracked the nation’s overall racial breakdown. “All of those things are coming together in this moment,” Foy, a Pentecostal reverend, told me. “You have not just black people on the streets … You have all of diverse America on the streets.”

Despite the legendary status of the ’60s demonstrations, recent protests have likely involved more people. King’s March on Washington attracted 200,000 to 300,000 people to the Lincoln Memorial in August 1963; the anti-war March on the Pentagon brought probably 50,000 to 100,000 people in October 1967. Although exact numbers aren’t available, millions of Americans may have participated in protests since Floyd’s death. In the Kaiser poll, 10 percent of American adults say they have joined in the demonstrations, a result that would translate to some 25 million people.

The women’s marches the day after Trump’s inauguration also brought out millions, but only for a single day. The ongoing Floyd protests may represent the most Americans who have protested in the streets on a sustained basis since the demonstrations that followed the killing of four anti-war protesters at Kent State University in May 1970, when about half the nation’s college campuses erupted in discontent.

Nor have the current protests shown any sign of flickering out. Foy’s group, for instance, is organizing motor caravans in 33 cities on Juneteenth to demand independent investigations into people who have died at the hands of law enforcement and call for sweeping reforms in police procedures. One distinctive element of the project is that the local groups will also be encouraging participants to register to vote.

That latter focus represents one of the biggest uncertainties about the current wave of protest. The ’60s movements were divided between those who wanted to influence elections and engage with elected leaders (an instinct strongest within much of the civil-rights movement’s leadership) and those who disdained traditional politics as unlikely to produce fundamental change (a tendency strongest in the initial years of the anti-war and student movements). “There were very few people who came out of the new left who were ready to plunge into electoral politics,” says Gitlin, who served as president of Students for a Democratic Society during the ’60s and later wrote a classic history of the period, Years of Hope, Days of Rage.

Reporters following the current protests have found no shortage of local activist leaders equally suspicious of mainstream electoral organizing. One of the pivotal questions of American politics over the next decade may be how quickly, if at all, the young people now protesting in the street develop electoral clout comparable to their numbers. While the Baby Boomers changed social attitudes and popular culture relatively quickly, they did not elect one of their own as president until Bill Clinton, in 1992. In fact, with only one four-year interruption (Jimmy Carter), Republican presidents who largely positioned themselves against the cultural changes that the ’60s unleashed occupied the White House from 1968 until Clinton’s victory.

While the ’60s movements contributed to important changes in law on issues from civil rights and voting rights to the environment and decriminalizing private sexual behavior, their supporters’ failure to win subsequent presidential elections is the reason why Gitlin summarized their impact this way: They were “a great political defeat and a great cultural success. That’s how we ended up with the left marching on the English department while the right took Washington.”

The next decade could produce a similarly bifurcated outcome for Millennials, Gen Z, and the even younger (and more diverse) cohort following them. Their preferences already dominate popular culture, and their tolerance of diversity has lit the path for broader changes in social attitudes, such as public support for gay marriage.

But their electoral impact remains less defined. There’s widespread agreement among activists and observers alike that the election of Trump—a candidate who overtly defined himself in opposition to racial and cultural change—has created a sense of embattlement that’s fueled the expanding protest. “We are seeing those accomplishments, the things that people died for, Martin Luther King and Malcolm X died for, literally being stripped from us,” Foy said.

But, despite their animosity toward Trump, only about half of eligible Millennials and Gen Zers voted in 2016. And while turnout among younger voters was much higher in 2018 than in the previous midterm election, in 2014, many surveys have found only modest enthusiasm among them for presumptive Democratic nominee Joe Biden. Significant numbers of younger voters say they are considering either voting for a third-party candidate or not voting at all.

The energy coursing through the current protests—as well as Trump’s decision to position himself against them—might offer Biden a new opportunity to engage younger voters who have been cool to him so far. The payoff would be enormous if he can: Frey calculates that Millennials and Gen Z will comprise almost exactly as large a share of eligible voters in November as Baby Boomers and their elders do now (just under two-fifths in each case). By 2024, that balance will tip toward the younger generations, and the gap will widen steadily after that.

“Millennials are a bridge between the white-baby-boom-dominated culture of the past and the diverse America that will define the nation in the 21st century,” Frey told me. “I think these protests, made up of multiethnic Millennials and Gen Zers, are the tipping point of this shift.”

While the past decade’s social movements focus on discrete issues, all of them, as Wessel notes, are drawing on “the same frustration: We have an unequal society that benefits the few—the old, the white—over the many: the young, people of color. That is the crux of all these conversations.” Trump’s political strategy relies on mobilizing the Americans on the winning side of that contrast. Like the Baby Boomers during the 1960s, the younger generations dissatisfied with those arrangements have demonstrated, year after year, that they can fill the streets in protest. Their next test is to do what the baby boom could not: tip the outcome of national elections while they are still young.

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