Several months ago a slender volume on slavery and the United States Constitution by my friend Sean Wilentz waded ashore in Massachusetts, courtesy of Harvard University Press, found a friendly reception at Harvard itself, fought its way inland, captured a lower hill at The New York Times Book Review, penetrated the swamplands of The Nation, came under withering attack from tanks and airships at The New York Review of Books, returned fire, came under further attack in the letters column, attracted allies, escaped into the hinterlands, and by now has a good prospect (if I judge the reviews correctly, and especially the outcome of the pitched battle at The New York Review, this past June) of planting its flag above the United States as a whole. It may take 20 years, but the result will be salutary.

Wilentz’s book is No Property in Man: Slavery and Antislavery at the Nation’s Founding, and (if I allow my predictions likewise to march hither and yon) the argument it proposes will reshape American thinking on a deep American matter, which hinges on an absurdly simple question, to wit: When the United States was founded, was it fundamentally a center of oppression, pretending to be a progressive advance in human affairs? Or was the United States authentically a progressive advance, disfigured by some inherited traits?

The immediate topic is the several clauses of the Constitution that bear on slavery, and how to interpret them. Those are the barbarous clauses—the clause that distinguishes between “persons” who are “free,” and “persons” who are not, with the latter to be tabulated as three-fifths of the former; the clause mandating that any “person” who is “held to service or labor” in one state and escapes to another state shall be returned; and, among other stipulations, the clause forbidding Congress for 20 years from interfering, except in a small way by taxation, with the “Importation of such Persons as any of the States now existing shall think proper to admit”—which was a delicate reference to the African slave trade.

The clauses were approved at the Constitutional Convention at Philadelphia in 1787, principally on the demand of pro-slavery zealots from the Lower South. And the dispute over how to interpret them began at once, with the pro-slavery zealots taking an expansive view. The clauses, in their interpretation, signified a larger constitutional endorsement of slavery, which rested on respect for slavery’s underlying principle, which was a right to an extreme version of private property, with property deemed to extend to the ownership of human beings.

Wilentz tells us that, after the convention, the pro-slavery zealots launched something of a campaign to sell the world on their interpretation. And the campaign had successes. The leaders of the white South as a whole came to insist on those particular understandings, and Federal judges ended up accepting the interpretation. Eventually the Supreme Court itself agreed and, in the Dred Scottdecision in 1857, imposed a broadly pro-slavery interpretation of the Constitution on America as a whole, and not just on the slave states, as if branding a giant S on America’s forehead.