Centrism is having a bad year. Just ask the socially liberal, economically conservative Howard Schultz, who has created the least relevant presidential campaign in America – and I say that as someone who shares his basic outlook.

The problem with centrism, to be blunt, is centrists. One of the consequences of today’s polarized political environment, paradoxically, is that it is no longer tenable to claim to be above party politics. If they want their ideas to gain any traction, centrists will have to become more partisan.

It wasn’t always this way. For decades in the middle of the 20th century, the parties were ideologically scrambled, with liberal Republicans and conservative Democrats. Politics was governed by what economists call the median voter theory: When two sets of policies are offered, voters will support whichever one is closest to their personal views. Liberal and conservative voters will tend to support liberal or conservative policies, respectively.

The real battle, under this theory, is for the support of the median voter – the one who stands in the exact center of the electorate. If a liberal (or conservative) policy can just win her support, then it wins the support of everyone to her left (or right) and thus a majority of the electorate.

More recently, however, and especially in the last two decades, the parties have become more ideologically distinct. The median-voter theory doesn’t quite apply anymore. Elections are more like sporting matches than referendums on ideas, with voters supporting their team more than any particular set of policies.

As a result, if a liberal politician enthusiastically embraces a centrist idea, she may bring a handful of “median” voters to her side – but she will alienate even moderate conservatives. It becomes a blue-team idea, and any red-team member who supports it is suspect. This shifts the playing field, ultimately reducing the number of voters who support centrist ideas.

For an illustration of this phenomenon, look no further than the presidency of Barack Obama. In a widely heralded mea culpa, prominent center-left economist Brad Delong apologizes for ever having believed that Republicans could be negotiated with. Obama tried to build a broad coalition with “Mitt Romney’s health care policy, with John McCain’s climate policy, with Bill Clinton’s tax policy, and George H.W. Bush’s foreign policy,” he notes. “And did George H.W. Bush, did Mitt Romney, did John McCain say a single good word about anything Barack Obama ever did over the course of eight solid years?”

DeLong is not necessarily wrong, but he misses the point. For most Republican voters, the provenance of the Affordable Care Act – it was based on ideas originally proposed by the far-right Heritage Foundation – was irrelevant. The crucial fact was that Obama supported it; it was therefore a blue-team idea. Its “centrist” qualities won it few, if any, converts.

Republicans aren’t the only voters who react this way. President Trump’s isolationist rhetoric, for example, should appeal to Democrats, who have traditionally been more wary of U.S. involvement in other countries’ affairs. Yet it has caused support for intervention to soar among Democratic voters. This is although it would presumably be Trump who was managing such interventions.

Strangely, an ideologically tribal world would actually benefit from a president who holds partisan views yet is pragmatic in their execution. Policymaking in such a world is more akin to diplomacy. In the same way that only Nixon could go to China, maybe only Trump can reform the U.S. immigration system. Under this logic, the key to making a deal with the opposing party is not necessarily the details of the agreement; it’s a president’s credibility with his base.

Trump certainly has the intense devotion of the Republican base and a pragmatic, deal-making disposition. He falls short because his pragmatic streak is fickle and erratic. He lurches from promising deals to offering ultimatums with no clear sense of direction.

Nonetheless, the polarized state of U.S. politics means that future presidents are more likely to be cast in Trump’s mold than in Obama’s. To be relevant, political centrists will have to evolve. Their role is not to be high-minded technocrats lecturing less sophisticated extremists. Instead, they will have to embrace the role of humble emissaries willing to do the dirty work of getting their fellow partisans the best terms possible.