The American obsession with people who are said to transcend race began long before Barack Obama moved into the White House — long before he even thought about running for president. Affluent, well-educated black people were being appropriated as symbols of racial progress — and held up as proof that racism no longer mattered — back when Mr. Obama was still a youth in short pants.

White Americans have little experience with this brand of appropriation. In general, their personal and professional triumphs are viewed as the product of individual fortitude and evidence that the founding ideals of the nation are alive and well.

Successful African-Americans — whether they are sports stars, entertainers or politicians — are often accorded a more tortured significance. In addition to being held up as proof that racism has been extinguished, they are often employed as weapons in the age-old campaign to discredit, and even demean, the disadvantaged.