Governor Mario Cuomo used to ruefully observe that "you campaign in poetry; you govern in prose." Even honorable campaigns that confine their promises to the realm of the possible strive to suggest that a shelf of prosaic plans add up to something greater, something transcendent that justifies the level of emotional investment that even the lowliest volunteers make in a political contest.

That investment is essential to victory, as any losing campaign blamed for lack of the "vision thing" can attest. Races rarely go to the candidate who is best-prepared or most knowledgeable; they frequently go to the candidate who voters come to trust, who gives them reason to believe in them.

For some candidates, veteran legislators in particular, that necessity is maddeningly unfair. But Cuomo's comment was rueful because he was one of those politicians who really would have preferred to govern in poetry, but who was wise enough to know that was impossible.

Which brings me to Marianne Williamson.

Williamson is having her moment precisely because she, more than anyone else, is campaigning unequivocally in poetry — and a brand of poetry with far broader appeal than many media elites may have realized. She recognizes that Trump is a symptom of an American spiritual crisis, and that for a politics to be truly responsive to Trump it will have to be responsive to that crisis as well.

The rhetoric of that response has to operate on a level beyond practical solutions to some of the material problems that have produced that crisis. One of the most resonant moments in the second Democratic presidential debate was Williamson's line: "If you think any of this wonkiness is going to deal with this dark psychic force of the collectivized hatred that this president is bringing up in this country, then I'm afraid that the Democrats are going to see some very dark days."

Without endorsing the literal reality of psychic forces of either the light or dark variety, I think she has a point. At a minimum, it is plain that the most carefully calibrated health-care plan will not win the trust of an electoral college (and Senate) majority sufficiently large to decisively repudiate the Trump years — which is what it would take to make that very plan a practical reality.

But the point of a politics of poetry is, ultimately, to enable a government of prose. Correctly sensing the spiritual needs of the moment can help win the electorate's trust, and thereby build deeper support for a political agenda that addresses those needs. It can even help inform what that agenda might be. But expecting politics to achieve spiritual goals directly is a recipe for disappointment and disillusion.

That's why it worries me that the issue on which Williamson was the most persuasive — and, in fact, the most concrete — was reparations for slavery.

To her great credit, Williamson understands two things about reparations that seem to have eluded many of the other candidates who have nonetheless endorsed the concept in one form or another. First, reparations needs to have a specific meaning as a financial transfer that settles a longstanding debt. Williams has set a figure of $200 to $500 billion, saying those numbers should be politically achievable and anything less than $100 billion would be an insult.

Second, the case for reparations does not rest primarily on its practical utility in addressing social problems. On the contrary, the true purpose of reparations is spiritual, to heal the nation by relieving it of a weight of guilt and resentment over a debt long overdue and still unpaid.

And therein lies the rub. The promise of healing, of spiritual reward, is not one that can be reliably delivered on. Not only because it is unlikely that the people of the United States will truly come together over the question of reparations, but because that's not the way national healing works.

Consider the case of post-war Germany. Germany's immediate objective in the post-war years was to win readmission to the family of nations, and offering reparations to Jewish survivors and the families of victims of the Nazi murder machine was crucial to that effort, as was establishing relations with the new Jewish state. This was only the beginning of the process, however, and the next generation undertook a far more comprehensive effort to come to terms with Nazism and its roots in German culture. It is fair to say that Germany has done more than any other modern nation to reckon with its historic crimes, in very much the way that many advocates of reparations believe America must do. But that has not brought spiritual redemption — indeed, the "problem" of German history will not go away, to the point where in some quarters the whole project of spiritual reconstruction through historical reckoning has come into question.

That doesn't mean reparations are a fool's errand. There's something to be said for doing something simply because it is right. And the impact on the African-American community, spiritual as well as material, cannot be gainsaid. But the spiritual benefits to the nation as a whole that Williamson is promising are likely as evanescent as the medical benefits of visualizing angels in cancer cells.

Williamson is vanishingly unlikely to win the Democratic nomination; so far, she hasn't even qualified for the next debate. But her spiritual message has far broader resonance in the Democratic Party than her candidacy does, as evidenced by the numerous other candidates — including wonky ones — who have embraced unpopular policies in the same of national purification. That's reason enough to listen to what she's saying.