In a country as thoroughly divided as ours, the parties at the heart of our political life spent the past two weeks trying very publicly to overcome the deep fissures in their ranks. Now, having had limited success in smoothing over their intrafamily squabbles, the nominees of those two parties must try to convince us they can bring together one nation.

In the battle between Donald Trump and Hillary Clinton, the one who best convinces us he or she is up to this task will face the iffy chance that unity can be magically achieved. And failure to bring us together may well deepen a grinding gridlock already so extreme that Congress and Barack Obama haven’t agreed on a meaningful piece of legislation in years. That can’t be allowed to happen. This newfound political passion in both parties has to be channeled into progress for the nation.

The divides in the parties are similar yet different, creating struggles that have played out in mirror-image fashion.

A year ago, Trump launched a revolution against every wing of the GOP. This billionaire whose name is synonymous with New York glitz nabbed the nomination of a party whose power base is firmly Southern. He thumbed his nose at the hawkish neocons who led the party’s foreign policy, had little in common with the evangelicals who set the GOP’s anti-abortion, anti-gay moral agenda, never even acknowledged the libertarian wing and savaged the big-business free-traders who have funded Republican politics for decades.

By tapping into boiling anger against crony capitalism, immigrants with dark skin and unfamiliar cultures, the flight of manufacturing jobs and the stifled speech of political correctness, Trump used the fear and insecurities of GOP voters to crush 16 Republican candidates. At the national convention in Cleveland, the man who came closest to beating Trump and had one of the highest political profiles coming into the race, Texas Sen. Ted Cruz, stood up for the hallowed policies of the party, but not the nominee, pointedly telling attendees and the nation to “vote your conscience.” He might have hoped party regulars and delegates would cheer his stand, but they jeered and booed as Cruz scuttled off the stage.

Within the Democratic Party, an equally fiery and not dissimilar insurrection led by Vermont Sen. Bernie Sanders failed. The Brooklyn native took 22 states with a populist form of progressive politics that was built on the deepest societal hopes of generations of liberals, but he could not overcome the party apparatus. More important, Sanders and his followers could not overcome Clinton’s claim that she shared his dreams and her pragmatic argument that she’d do better than him in bringing them to fruition.

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On policies like a higher minimum wage, affordable college, access to health care and combating racism and sexism, any differences between Clinton and Sanders were of degree. The areas in which Sanders really could draw a huge distinction between himself and Clinton were often the same ones that powered Trump’s support against the Republicans he defeated: the piles of Wall Street money behind candidates, their hawkish military tendencies and their support for decades of free-trade agreements that boosted corporate profits but exported middle-class jobs. But in the Democratic Party, unlike the GOP, the grass-roots movement did not carry the day.

Sanders, unlike Cruz, took to the convention stage to tell those on his side of a divided party that they needed to let go and come together. Sanders was cheered by his opponent’s supporters and jeered by some of his own, who felt he had sold out their passion to a compromised candidate working for a meeker vision. But Sanders’ willingness to swing to Clinton and fight wholeheartedly against Trump was rewarded with prime speaking slot for himself and an acceptance speech by Clinton Thursday night that highlighted point after point his run had prioritized.

In November, we will vote in this race and in House and Senate contests that have as much to do with how and whether the nation moves forward. The results of that election could clarify the paths of these two parties, or not. The only clear truth for both is that they cannot remain beholden to moneyed interests that ignore the needs of the people and cling to economic and political principles that don’t apply to a changing world.

Neither candidate or party will get anywhere if it wins with a slim majority and is forced to try to govern against a slightly smaller, enraged minority. It’s the common causes shared by the insurrections in the two parties that must be grasped if we are to advance as one nation. In a healthy United States, the broad majority must prosper and be empowered. Peace and public safety must abound. Where economic and employment realities change, society must soften the harsh impacts of those changes. Excellent education must be available to all.

These are the only ways to quell the fears and insecurities of those who voted for Trump, and the anger and disaffection of those who voted for Sanders. And that’s the only way for our next president to succeed.