At 9:00 p.m. on Sunday, March 31, 1968, Lyndon B. Johnson delivered a televised address to the nation. After discussing his intention to de-escalate the Vietnam War, he soberly declared, “I shall not seek, and I will not accept, the nomination of my party for another term as your president.”

The decision was shocking, coming less than four years after Johnson had won one of the greatest landslide victories in presidential history. The context, however, made it understandable. Johnson confronted intense antiwar opposition, simmering urban violence and growing inflation. He also faced a serious electoral threat from two Democrats challenging his renomination, Sen. Eugene McCarthy of Minnesota and a longtime Johnson adversary, Sen. Robert F. Kennedy of New York. And both were polling close, if not ahead, of him.

This announcement has come to represent the unraveling of Johnson’s presidency, the Democratic Party and postwar liberalism more broadly. The footage of his remarks shows a man psychologically and physically beaten down by the burdens of the office. Yet it also reveals how much the Democratic Party has changed in the past 50 years.

With the Democratic Party once again at a crossroads, this anniversary offers a chance to reflect on Democrats’ uneasy relationship with the legacy of Johnson and the Great Society. While Johnson’s rhetoric lionizing government as the vehicle for solving social problems may have gone out of fashion, his programs, which do just that, have become inextricably embedded in American political life.

More than representing a Democratic Party in disarray, McCarthy and Kennedy’s challenges to Johnson in 1968 reveal the beginning of a shift in the Democratic base. During the 1970s, that base moved away from white southerners and industrial laborers in the North and Midwest and toward many of the voters who supported these insurgents, including white-collar suburbanites, young people and members of underrepresented groups. Beyond simple demographics, this new base questioned the ideological basis of Johnson’s liberalism, especially its faith in the federal government to fundamentally refashion American society.

Despite George McGovern’s landslide loss in the 1972 presidential race, the party continued to gather strength in the 1970s. Called the “Watergate babies,” more than 70 Democrats — including Gary Hart, Jerry Brown, Michael Dukakis and Paul Tsongas — swept into the Capitol and statehouses in 1974, largely because of the white suburban areas that had come out in support of McCarthy and McGovern. These politicians promised to stop the war in Vietnam, end corruption and make government more efficient and transparent.

The group took aim not just at Richard M. Nixon and Republicans, but also the Democratic establishment, which remained embodied by Johnson. James Blanchard, a freshman representative from Michigan, distanced the Watergate babies from the party’s history: “Clearly we don’t see ourselves as New Dealers at all — or proponents of the Great Society.” And while they agreed with Johnson’s commitment to stimulating economic growth, they eschewed the Great Society for increasing bureaucracy.

They also moved away from the Democratic Party’s long-standing relationship with organized labor. Their approach was to bolster the high-tech and postindustrial sectors by forging close partnerships with businesses and corporations. Although not officially a Watergate baby, Jimmy Carter echoed these themes of reducing the size and reach of government, implementing market-oriented ideas such as deregulation in  his campaign and agenda as president.

In the 1980s, a new generation of politicians, notably Bill Clinton and Al Gore, embraced the label “New Democrats” with an explicit goal of “reinventing”  the party and government. Through their newly formed Democratic Leadership Council (DLC), they worked to win the support of moderate swing voters and the white working class. The DLC sought to shift the party’s priorities by redefining the Democrats’ “fundamental mission” as “expand[ing] economic opportunity, not government.”

Whereas Johnson waged his “War on Poverty” with the Office of Economic Opportunity and Community Action Programs, the DLC advocated market-oriented programs such as empowerment zones and welfare-to-work to address poverty and inequality. These ideas animated and shaped Clinton’s presidency as he sought to fulfill his campaign promises to create “a new approach to government” that “offers more empowerment and less entitlement. … A government that is leaner, not meaner; a government that expands opportunity, not bureaucracy.”

This set of ideals and the accompanying policies remade American liberalism and the Democratic Party. During his 2012 State of the Union, Barack Obama channeled Clinton, not Johnson, when he argued that “our government is leaner, quicker and more responsive to the needs of the American people.” It is no coincidence that this claim occurred the same year as his reelection campaign. It epitomized his efforts to appeal to the type of moderate voter that the DLC had decades earlier deemed critical to the party’s success.

But even as Democrats — from Bill Clinton to Obama to Hillary Clinton — have perennially criticized Johnson’s approach and aimed to forge an alternative electoral strategy, they have continued to fight to preserve key aspects of his agenda. Great Society programs — from Head Start and food stamps to Medicare — have remained enduring party priorities. Johnson’s abiding commitment to increasing opportunity, empowering individuals and improving quality of life have also remained core tenets of the Democrats.

The efforts to preserve these bedrock programs and ideals while at the same time promoting pro-market and small-government solutions have created key tensions and contradictions in the party’s platform, dilemmas for its electoral strategy and the government interventions the party still aims to protect. The Democrats confront fundamental challenges as they seek to simultaneously pursue frustrated Republicans and satisfy their now-traditional base of affluent white-collar workers, young people and members of underrepresented groups. These groups want different (and often conflicting) things, which poses the risk of alienating key constituencies. It is notable that while Hillary Clinton had historically high rates of support among white college-educated voters in 2016, turnout rates among African Americans declined, especially in low-income areas.

Fifty years ago, Johnson created a vast opening in the Democratic Party by leaving the presidential race. In his wake, the party made affluent suburban voters its priority and used a message of government efficiency and a faith in the market and public-private partnerships to win them over.

And it seemed to work — until now. Why? Because this approach also created fundamental fissures among the party’s supporters. Unable to provide meaningful and stable assistance to less fortunate people, Democrats struggle to secure their support on Election Day. Until they resolve that tension, bridging the divide opened in 1968, Democrats will continue to squander the opportunities created by a confused GOP.