Just two weeks ago, many Democrats were anticipating a harmonious end to their party’s unexpectedly prolonged presidential primary. They envisioned a scenario in which the forces of division within the party, which had recently intensified, might collapse under the weight of enormous historical forces.

Back then, though Hillary Clinton’s lead in California primary polls was an imposing 10 percent, her head-to-head lead in general election polls over Donald Trump had vanished. Trump had consolidated Republican support more rapidly than seemed possible after clinching his party’s nomination, and the notion that Democrats needed to put their primary behind them before Trump claimed the lead had taken on new urgency.



A resounding Clinton victory in the country’s most populous blue state, on the same night that she was projected to eclipse the number of delegates required to win the nomination, seemed like just the jolt the party would need to form a consensus behind her candidacy, against a surging Trump. With the nomination out of reach, Bernie Sanders might even concede defeat, while declaring a moral victory for a rising progressive wing of the Democratic Party.

It was never going to be quite so smooth. Around the same time, I argued that as a matter of political horse-trading, Democrats were going to have a harder time unifying their party after Clinton finally vanquished Sanders than they did in 2008, when Barack Obama defeated her. Unlike Clinton and Obama, Clinton and Sanders have substantial ideological differences, and substantially different theories of how the political system responds to public sentiment. When Obama beat Clinton, Democrats were desperate for a path out of the political wilderness; eight years after the George W. Bush presidency ended, it stands to reason that some of them have become frustrated by the Democratic establishment’s many inadequacies.

The events of the last two weeks have made unity more challenging still. The way the Clinton-Sanders race came to an end, amid signs that Trump’s general-election campaign will be a convulsive disaster, will only amplify the forces keeping the party divided. And the longer it remains divided between Clinton and Sanders supporters, the more marginalized and alienated Sanders’s supporters will grow, and the more attenuated Sanders’ influence—and the left’s—within Democratic politics will become.