If the rhetoric is to be believed, there has been a quite dramatic reversal in America's racial thinking. Black people, who used to long for the day when race would matter no more than, say, eye color, now seem intent on elevating it to overarching significance. White people, who perfected both the concept and its discriminatory application, are wondering why black folk keep obsessing over race when they themselves are completely (if belatedly) colorblind.

White people, for example, were quite willing to accept the multiracial lineage of Tiger Woods -- his Thai and Chinese mother and his black, white and Indian father -- or, in the alternative, to forget about his race. It was blacks who excoriated the young golfer -- sometimes for his naivete ("Cablinasian" indeed. He'll wake up when somebody calls him the "n" word.), sometimes for his racial forgetfulness (They make it to the big time and quickly forget where they came from.).

White racists created the absurd notion that blackness could not be diluted away by any amount of whiteness, while a single drop of black blood could render you and your descendants black forever.

And now that white people declare themselves ready to drop such silliness, black people are buying it with a mind-boggling earnestness. What was a badge of dishonor imposed upon a race of slaves is now defended as our essence.

What is this thing we call race? It is color and hair and lips, of course, but it is a lot more -- and a lot less -- than these things.

Two things have me thinking about the peculiar essence of race. One is the forthcoming book, "Half-Jew," by Susan Jacoby, an erstwhile journalistic colleague who played detective well enough to prove that her father was a Jew, though he spared no effort to conceal that fact from his children. He joined the Episcopal Church, married an Irishwoman and created a phony personal history while sending his children to Catholic schools.

The daughter, having proved what she already suspected, now feels moved to identify with the Jewish element of her heritage. But with what, precisely, would she identify? I have always thought of Jewishness as some combination of religion and culture, perhaps with a few identifying physical features that might admit of a racial categorization. But Jacoby lacks these physical features, had no link to a Jewish culture (thanks to her father) and is an atheist. Wherein is the Jewishness she would claim? Is it only the suffering of the Jewish people that makes her think she ought to claim it? If she had been brought up as a cultural but nonreligious Jew, would the discovery that her ancestry was entirely Gentile prompt her to dis-identify with Jewishness?

Here's the other thing that has me thinking these thoughts: A recent issue of the London Sunday Telegraph has a story quoting a leading British geneticist as saying that at least one Briton in five has black genes, making some 11 million ostensibly white Britons the racial kin of Afro-Caribbeans.

"Many people who think of themselves as white -- although they may not want to admit it -- have a black ancestor," said Steve Jones, an academic at University College London. "We have to accept that the rivers of genes which flow through history run into each other all the time."

Supposing Jones has it right, does that mean (as in the American one-drop calculation) that these 11 million Britons are black? Does it mean they would be subject to "outing" if their DNA became known? Or does it, as seems to be the reaction in Great Britain, mean nothing?

Sometimes, of course, it means nothing here. President Clinton's claim of Cherokee ancestry hasn't led anyone to question his whiteness, though Madeleine Albright's misplacement of her Jewish background proved at least a temporary political embarrassment. The more general reaction in both cases, I suspect, was: Who cares?

Has America reached the point where most whites -- where even a significant minority of whites -- really don't care about race? Black Americans would respond with a resounding NO!

Should race be irrelevant -- something we notice, such as eye color, but keep out of our judgments of people? It wouldn't surprise me if a greater percentage of whites than blacks answered that one in the affirmative.

Maybe it's because history has made color such an integral part of who we are and how we see ourselves. Or maybe it's because we don't yet dare to trust people who tell us they are indifferent to race -- whatever race is.