The reaction to Ta-Nehisi Coates' magisterial essay on the lingering effects of American racism is polarized around people's reaction to the word "reparations." But much of the story he tells is about something simpler, and completely uncontroversial: the power of compound interest.

You might remember, as a kid, getting this problem on a test: Would you rather have $10,000 per day for 30 days or a penny that doubled in value every day for 30 days?

The answer, of course, is you want the penny that doubles in value every day. If you take the $10,000 you end up with $300,000 after the first month. Take the penny and you end with about $5 million.

What Coates shows is that white America has, for hundreds of years, used deadly force, racist laws, biased courts and housing segregation to wrest the power of compound interest for itself. The word he keeps coming back to is "plunder." White America built its wealth by stealing the work of African-Americans and then, when that became illegal, it added to its wealth by plundering from the work and young assets of African-Americans. And then, crucially, it let compound interest work its magic.

Today, white America is one of the richest and most powerful populations the world has ever known. And it wonders why African Americans just can't seem to keep up. "In America," Coates writes, "there is a strange and powerful belief that if you stab a black person 10 times, the bleeding stops and the healing begins the moment the assailant drops the knife."

Though the sums are gargantuan — using standard government calculations, the theft from slavery alone stretches into the quadrillions of dollars — it's relatively easy for people to think in terms of the compound interest that's accrued to the income stolen from African Americans. But the power of compound interest doesn't just apply to money. It also applies to education and families and neighborhoods and self-respect. And this is where Coates' piece is so devastating. America didn't just plunder what African-Americans earned, or what they had saved. By far the hardest part of the piece to read was this account of what slavery did to black families:

Forced partings were common in the antebellum South. A slave in some parts of the region stood a 30 percent chance of being sold in his or her lifetime. Twenty-five percent of interstate trades destroyed a first marriage and half of them destroyed a nuclear family. When the wife and children of Henry Brown, a slave in Richmond, Virginia, were to be sold away, Brown searched for a white master who might buy his wife and children to keep the family together. He failed: "The next day, I stationed myself by the side of the road, along which the slaves, amounting to three hundred and fifty, were to pass. The purchaser of my wife was a Methodist minister, who was about starting for North Carolina. Pretty soon five waggon-loads of little children passed, and looking at the foremost one, what should I see but a little child, pointing its tiny hand towards me, exclaiming, "There's my father; I knew he would come and bid me good-bye." It was my eldest child! Soon the gang approached in which my wife was chained. I looked, and beheld her familiar face; but O, reader, that glance of agony! may God spare me ever again enduring the excruciating horror of that moment! She passed, and came near to where I stood. I seized hold of her hand, intending to bid her farewell; but words failed me; the gift of utterance had fled, and I remained speechless. I followed her for some distance, with her hand grasped in mine, as if to save her from her fate, but I could not speak, and I was obliged to turn away in silence."

If you believe in the power of strong families to help all their members do better in life — and almost all the research says you should, and almost every American politician says they do — then think about the value of that family, unbroken rather than broken, compounding down through the generations. The same goes for the houses stolen from African-Americans and the educations they wanted but couldn't have and the basic belief in US law and institutions that whites take for granted but does so much to make everyday life easier.

"The popular mocking of reparations as a harebrained scheme authored by wild-eyed lefties and intellectually unserious black nationalists is fear masquerading as laughter," Coates writes. It's also the intellectually unserious response of people who believe that because they never owned slaves or drank from a whites-only water fountain they weren't the beneficiaries of American racism. They may not be the villains of American racism, but they are the beneficiaries of it. The average white southerner in 1832 was far poorer than the average white southerner today, and part of that vast increase in wealth and income and knowledge and social networks is the result of compound interest working its magic on what the slaveowners and the segregationists stole.

It's as simple and clear as a child's math problem. The people who benefitted most from American racism weren't the white men who stole the penny. It's the people who held onto the penny while it doubled and doubled and doubled and doubled.