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We may be the better part of two years away from the next presidential election, but the central Democratic narrative of the coming campaign has already come into clear focus. Democrats are poised to employ a two-pronged strategy. First, they’ll speak to the electorate’s festering personal anger with President Donald Trump. Second, they’ll promise a bevy of new benefits, including some combination of Medicare for All, free college for all, the Green New Deal, and reparations.

Here’s my concern. While both these strategies may have something to recommend them, Democrats are missing a crucial third prong. While we are fighting for new rights, we also need to demand a reinvigorated sense of responsibility. We cannot simply promise the country more—we need also to ask more of one another. The Democratic Party is strongest when we challenge the public to give, not just promise the public more of what they get.

That’s not to distract from the challenges of inequality or the demands of social justice. The voters who make up the “Metropolitan Majority” that Democrats will have to win over in future campaigns unquestionably want to rebalance the relationship between the people and the powerful (to borrow Al Gore’s 2000 campaign theme).

Democrats, however, also need to address a crisis bubbling below the surface: the sense that the country is being ripped apart, that red and blue America are alienated from each other, and that America’s higher moral purpose is being shredded by the divisive tenor of the national debate.

At a moment when Americans are in search of a spiritual reawakening, we need to avoid the temptation to speak to voters only in a single dimension. The Democratic Party should offer a vision of citizenship that contrasts with Trump’s celebration of hedonistic consumerism. We should call on the nation’s sense of deep-seated patriotism to rebut his ugly nationalism. We must champion a spirit of unity and purpose that counteracts his self-serving schemes to pit one community against the next.

We can begin by issuing a simple but powerful call: a policy that requires all 18-year-olds to give at least six months of their life to national service. People from different walks of life, with different backgrounds, would serve with one another as a rite of passage. Once young adults graduate high school or reach college age, they would join the military, the Peace Corps, AmeriCorps, or some other service-oriented organization.

Some may recoil at the prospect of having to contribute anything more than they already do. But the Democratic Party’s greatest heroes have not simply extended the social safety net. Their success was born out of the nation’s desire to share in America’s mission to rid the world of tyranny. To beat back the specter of communism. To share the benefits of liberal democracy and free enterprise with societies mired in poverty and dysfunction.

Many may remember Franklin D. Roosevelt primarily for championing the New Deal. But when fascists rose up to threaten the free world, FDR inspired Americans to sacrifice in service to “the arsenal of democracy.” And it was that sense of shared purpose that most defined the character of the members of what came to be known as the Greatest Generation, including Roosevelt’s eventual successor, John F. Kennedy.

JFK, in turn, is often remembered for the famous line he delivered in his 1961 inaugural address: “Ask not what your country can do for you—ask what you can do for your country.” And that rhetorical flourish became a central theme of his administration. In 1961, he established the Peace Corps, a program that has since given 235,000 Americans the opportunity to extend America’s helping hand around the globe.

Subsequent Democratic leaders have thrived when calling on that same spirit of service. Few accomplishments were more meaningful to President Bill Clinton than establishing AmeriCorps, envisioned as a domestic version of the Peace Corps, through which more than a million Americans have now served their own (and often neighboring) communities. President Barack Obama beamed in 2009 while signing a vast expansion of the nation’s service programs two months after assuming office. (The bill was named for JFK’s brother Senator Ted Kennedy.)

Universal national service is not just good politics—it’s good policy. When the Baby Boomers were coming of age, calls to public service often channeled people into running for office. But Millennials have taken a different view, eschewing politics and focusing on community volunteering instead. Hopefully, we can convince future generations that politics is, indeed, an honorable profession. In the meantime, however, a universal national-service program will tap into younger Americans’ desire to serve the greater good. There are a variety of proposals out there, championed by figures such as retired General Stanley McChrystal, which set out the mechanics of how such a program would operate. But the specifics matter less than the principle such a call would reinforce.

No foreign power—not China, not Russia, not the mullahs or the terrorists—will be able to compete with America if we remain unified in our national mission to spread peace, equality, freedom, and prosperity to every corner of the country, and throughout the globe. That should be a key part of the Democratic Party’s approach to governing. And as I’ve seen from the thousands of kids who have participated in service programs such as City Year here in Chicago, that service is not only good for the communities that benefit—it feeds the souls of those giving back as well.

As Muhammad Ali once said, “Service to others is the rent you pay for your room here on Earth.” Trump is undoubtedly more than a disappointment, and America’s working and middle classes are certainly in need of new government protection. But against the backdrop of Trump’s call to consumerism, nationalism, and divisiveness, the third and potentially most powerful leg of the Democratic message should tap into America’s deep-seated patriotism and selfless citizenship. Nothing would stir that underlying sense of common purpose more powerfully than a call to universal national service. Nothing else would so fundamentally challenge Trump’s divisiveness.

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