My subject is really three subjects that together constitute a single theme at the heart of American life. First, slavery itself — that form of human relations by which, for more than two centuries, white persons exerted unappeasable power over black persons as if they were tools or livestock. When speaking about this subject, I try to keep in mind an admonition from William Wells Brown, a fugitive from slavery who spoke in the antebellum years to audiences in the North who were eager to hear in lurid detail what he had endured in the South. Most left disappointed. “I would whisper to you of slavery,” he told them. “Slavery cannot be represented; it can never be represented.” Reticence from a man who had known the thing itself should give pause to anyone who presumes to speak of it now. Second, there was — and is — the aftermath of racial subjugation that long outlasted the institution of slavery. For black Americans, that experience extended in space and time far beyond the Jim Crow South, and even many who have attained prosperity or renown still know it today in the form of condescension or contempt. This, too, is something of which no white person can have more than nominal knowledge. And finally there is the question of reparations — our shorthand word for the idea that a decent society must accept responsibility in the present for injustices perpetrated in the past. What this would mean in practice raises a host of moral, political, and personal questions — all of them urgent and none of them simple. What connection should one feel to acts committed or omitted before one was born? How can the cost be calculated of living at the mercy of a person who claims to own you, and of knowing that the same will be true for your children and their children? Even if one could compute the cost, who would fund the reparations, and to whom should they be paid? Would they be subject to means-testing and paid on a graduated scale like a sort of reverse income tax? In a society where identity is increasingly fluid and self-defined, who would decide who qualifies and who does not? Adjudicating these questions — and there are many more — will no doubt open more cracks in our already fractured country. But evading them, as the phrase goes, is not an option. A good place to begin is with Thomas Jefferson, who was both a fervent democrat and an unrepentant slaveowner. As such, he embodied what some would call the tragic paradox of early America and others would call bald hypocrisy. In 1775, when news of revolution in the colonies reached the mother country, Samuel Johnson inquired with acid scorn, “How is it we hear the loudest yelps for liberty among the drivers of Negroes?” Jefferson was at the bullseye of that question, and he knew it. “I tremble for my country,” he famously wrote, “when I reflect that God is just, and [that] his justice does not sleep forever.” His choice of word — “tremble” — tells us that, like many slaveholders, he feared that when justice came, it would come not as reconciliation but as retribution. Some fifty years later, the editors of Freedom’s Journal, America’s first periodical written and published by black people, agreed with him. “National sins,” they wrote, “have always been followed by national calamities.” But no one — neither the enslavers nor the enslaved — could foresee when or at what scale the calamity would come. Just before daybreak on April 12, 1861 — not quite thirty-five years after Jefferson’s death — it came. That morning, partisans of slavery, feeling both enraged and emboldened by the election to the presidency of a man who had promised to place slavery “in the course of ultimate extinction,” launched an artillery assault on Fort Sumter in Charleston harbor. President Lincoln responded by calling up seventy-five thousand volunteers to suppress what he called a “domestic insurrection.” After a three-month lull, the conflict resumed some forty miles from the nation’s capital, at Manassas, Virginia. As so often at the outset of war, both sides expected little more than a carnival show with pop guns. In the North, volunteers waved bits of rope with which they promised to lace up the rebels like trussed hogs. In the South, slaveowners boasted that all the blood to be spilled would barely fill a thimble. We know how those predictions turned out. Over four years of slaughter at places of previously small note — Shiloh, Antietam, Chancellorsville, Vicksburg, Gettysburg, Chickamauga — the scale of the calamity revealed itself. Writing about the first on that grisly list, General Grant recalled that the earth at Shiloh was “so covered with dead that it would have been possible to walk . . . in any direction, stepping on dead bodies, without a foot touching the ground.” Before the war was over, at least three quarters of a million bodies (equivalent to some eight million today) had been put under the ground, including roughly seventy thousand black soldiers who gave their lives fighting for the Union, not to mention countless formerly enslaved persons who, abandoned by their former masters, died of disease or starvation. President Lincoln never formally joined any church, but like most Americans of his time he was a believer. In his second inaugural address, delivered on March 4, 1865, on the steps of our recently desecrated Capitol, he quoted Matthew 18 — “woe to that man by whom the offense cometh” — to say that suffering on such a scale could only be due to the righteous wrath of God. And he was careful to identify the provoking sin not as southern slavery but as “American slavery.” Then he spoke a terrifying sentence, concluding with a line from Psalm 19: “If God wills that [the war] continue until all the wealth piled by the bondsman’s two hundred and fifty years of unrequited toil