Bryan Snyder / Reuters

A candidate appears on the stage of a Republican primary debate and praises single-payer health care in Canada and the United Kingdom. He upbraids the corruption of American campaign finance. He denounces the Iraq war. He scoffs at banks and bankers—and promises to renegotiate the U.S. national debt. He ranks (or anyway, ranked) first in all the polls for the Republican nomination. It sounds more like a scene from an Aaron Sorkin series than real-world politics. Yet it happened last night on Fox News.

More incredible still: The Fox interviewers hammered this candidate unrelentingly hard—and it is the interviewers, rather than the bold-minded candidate, who have been widely hailed as models of independence and integrity. To most actual Aaron Sorkin fans, meanwhile, the stereotype-smashing candidate himself remains something between a joke and a pariah.

Nor are the Sorkin fans wrong, necessarily. The candidate in question is Donald Trump, after all. But it’s worth thinking about why the man who in many ways qualifies as the most liberal Republican in the race should get so very little acclaim from those who have hailed the party’s great moderate hopes from Jon Huntsman to John Kasich.

Rand Paul did more with less. In 2014, he earned a glowing Time magazine cover by questioning police power, drug laws, and American interventions abroad. You can see why those positions would be congenial to Time. But why isn’t Trump at least “interesting”? His policy preferences are much more unpredictable than Paul’s. Paul is constrained by a coherent ideology, by the preferences of his donors and supporters, and by some internal commitment to consistency and sincerity.

Trump is burdened by none of these things. Like an electron in quantum mechanics, he can materialize almost anywhere in the political universe, obeying only some opaque internal decision-making of his own. No, he’s not “sincere.” No, he’s not “thoughtful.” He’s certainly not consistent. But he’s a genuine and even extreme maverick in a media environment that—one might suppose—relishes mavericks above all.

But he hasn’t received the fawning admiration of the political press corps, and the reason why is not mysterious. Modern liberalism admires three kinds of politics: equality politics, peace politics, and diversity politics.

Equality politics is the politics of wealth and income, of social insurance and retirement security. Peace politics is the politics of war, intervention, and surveillance.

Diversity politics is harder to define. It is the messy complex of issues that involves claims against the historic-American ethnic majority and traditional American gender roles. It’s not always clear in advance what these issues will be. One of Rand Paul’s clever strokes, for example, was to recast the traditional libertarian position on drugs (it’s your body, you should be able to put into it whatever you like, whether that’s cocaine or trans fats) in terms of diversity politics (drug prohibition bears too hard on disadvantaged minority groups). The first position is not “interesting” in the Time magazine sense of "interesting.” The second is.

The usual rule is that peace politics trumps equality politics. (That’s why the very fiscally conservative but intervention-skeptical John Huntsman attracted such favorable coverage in 2012. His stance on climate change helped too.)

But diversity politics trumps them all, as Bernie Sanders—a vociferous practitioner of both equality and peace politics—was reminded to his chagrin at this year’s Netroots Nation convention.

Trump was lofted into first place in the Republican polls by his noisy rejection of all the normal rules of diversity politics. He talked about immigration when few other politicians wanted to—and he talked about it in the way almost no other politician does, by insisting that immigration policy should be based upon the interests of the citizens of the United States first and foremost.

He didn’t talk about the subject very wisely, very well, or very effectively. But he broke the taboo, and that is what has brought him his audience. That is why he survived his ghastly remarks about John McCain and why he very likely will survive his poor performance in Ohio last night.

Trump has been derided as the Conservative Id and worse, and maybe all of that is true. It’s also true that diversity politics is a politics in which one side utterly dominates all conventional—even all legitimate—modes and channels of expression. Yet diversity politics remains politics, which means it remains contested.

If the contest is suppressed, it does not vanish. It erupts in ways that are extra-political and anti-political, led by figures who are half-demagogue, half-clown. We’ve seen that happen in Europe. In Italy, for example, the second-largest party in Parliament—the populist protest Five Star Movement—is led literally by a comedian. Trump is bidding for a similar role in the United States.

Such a project probably won’t work over the long run in the United States, for reasons both institutional and cultural. But in the short run, political energy and political dissent have to go somewhere. Fox News alone can’t get rid of Trump. He can’t be exorcised until the discontents that sustain him are given a better and more responsible way to express themselves.

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