It is worth remembering that when newcomers from Europe flocked to these shores in search of opportunity, they did not automatically see themselves as white. They were French, English, Scottish, Spanish or German, and far from having some identity in common, they were often in contention for the riches of this land. Whiteness was something that had to be learned and earned, particularly for those — Jews, Poles, southern Italians, Hungarians, the Irish — who were regarded as congenitally inferior. They were seen as white, says Painter, but it was a sort of defective whiteness. They were “off white” for want of a better term, and as such, a threat to American values and traditions. And they were mistreated accordingly until, over the passage of generations of assimilation, they achieved full whiteness.

University of Illinois history professor David R. Roediger recounts a telling episode in his book, Working Toward Whiteness. It seems David, a Russian Jew, has come to America seeking refuge from anti-Semitic persecution. He arrives in Georgia and begins working with his cousins as a peddler. But soon there is a problem. His cousins complain that he is too friendly with his black customers. “The schvarters here are like we are in Russia,” they explain. To treat them too well is to risk his own acceptance.

David replies that he cannot bring himself to treat the blacks as he himself was treated in Russia. “It is easy,” he tells his cousin, “for you to forget how to feel and what it is like to be hurt and stepped on when you think of yourself as white today and forget what it was like being a Jew yesterday.”

As Jon Stewart noted recently on The Daily Show, that history is what lends a certain pungent edge to some of the post-election hand wringing among conservatives. Surely, the gods of irony laughed aloud when a television personality named O’Reilly (Bill) and a guest named Goldberg (Bernie) lamented how newcomers were changing “traditional America.”

As whiteness was invented, so was blackness. When Africans were gathered on the shores of that continent to be packed into the reeking holds of slave ships for the voyage to this country, they saw themselves as Taureg, Mandinkan, Fulani, Mende or Songhay — not black. As Noel Ingnatiev, author of How The Irish Became White, has observed, those Africans did not become slaves because they were black. They “became” black because they were enslaved.

But though blackness and whiteness were invented they still, to a remarkable degree, govern perception — and thus, destiny.

Some months ago, my wife Marilyn and I were at dinner with two other couples and somehow, we all got talking about identity. One couple, brown-skinned like Marilyn and me, saw themselves, like Marilyn and me, as black or African American. The other, fair-skinned couple, pointedly declined to define themselves as white. She said she saw herself as Jewish; he defined himself as a first-generation Polish American.

It struck me, not simply because it underlined the ultimate falsity of these identities, white and black, but also because it highlighted what has always struck me as the problematic nature of one of them in particular: white. I’ve often thought the word “white” had a tendency to discomfit the people to whom it is applied, to carry some hint of accusation that is no less real for being unspoken. In my experience, white people are often ill at ease with being referred to as white people.