When Barack Obama, whose mother was white, identifies himself as black, and when Bill Richardson, whose father was white, identifies himself as Hispanic, who is white?
The U.S. Census Bureau says the country will be majority-minority in 2050 -- that is, the combined number of blacks, Asians, American Indians and Hispanics will put whites in the minority. Texas and California are already there.
The deepest racial divide, between blacks and nonblacks, endures. But there also are identity shifts among African-Americans, as Sen. Obama's success suggests. Some make it into the middle class, where education and social mobility may help shape their identities as much as race does. Others are left behind in increasingly segregated schools and neighborhoods.
They considered Nordic whites, from England, Scandinavia and Germany, the most ethnically desirable and elite, followed by the Alpine whites, from eastern and central Europe, and finally the Mediterraneans. Everyone else was identified as black, red, yellow or brown, which included South Asians.
Whiteness and the privileges that came with it were so closely guarded that in 1912, a House committee held hearings on whether Italians were really Caucasian, says Thomas Guglielmo, a historian at George Washington University. The idea was picked up from Italy, where northern, lighter-skinned Italians, were asking the same questions about the southern, darker-skinned Italians, he says. No one argued seriously that Jews and Greeks, or Irish and Poles -- light-skinned but poor -- weren't white, but whether they were ethnically Caucasian was up for debate, he adds.
In 1922, the Supreme Court decided that a Japanese man had white skin but wasn't ethnically Caucasian, and it denied him citizenship. A year later, it decided a South Asian was ethnically Caucasian but not white, and it denied him citizenship, too.
All of this because whiteness mattered a lot. Until 1943, only blacks of African heritage and whites could become naturalized citizens. Interracial marriage was illegal in some states until 1967, and some Jim Crow laws that protected white jobs, neighborhoods, voting rights and political power didn't fall until the 1970s.
Today, being white still has its privileges, but its meaning is changing now that those who are nonwhite face fewer legal and social barriers.
He sees today's black-white divide becoming a "black/nonblack" gulf.
Intermarriage is now common, blurring racial lines. Demographers estimate that about 8% of the U.S. population is mixed race, and almost one million multiracial children were born since 2000, when "two or more races" became a separate racial category on the Census form.
Opting Out of Whiteness
After the Sept. 11, 2001, terrorist attacks, there was "some sentiment" among non-Arabs for counting Arab-Americans as nonwhite, says David Roediger, a University of Illinois race historian. Since then, the Arab-American Institute in Washington has unsuccessfully lobbied the government for a separate "Middle East and North African" category on the census. snip
Some minorities or multiracial Americans who were once counted as white are opting out of the category. The population calling itself Native American quadrupled when the Census Bureau began asking people to identify themselves by race rather than relying on its own enumerators to do the job.snip.
Mexicans were long counted in the Census as whites because of an 1848 U.S.-Mexico treaty that allowed them citizenship; only whites and blacks could naturalize, so by that logic, Mexicans were white.
But since 1980, Hispanics have had a separate Census category where even intermarried, non-Spanish speakers can include themselves, if they choose. One in eight people in the U.S. does, including Latin American, European and Caribbean Hispanics and their progeny.
Identity groups that once lobbied to be accepted as whites now see advantages in being nonwhite, including college-admission and hiring preferences.
Some African-Americans who fear losing political power to the fast-growing Hispanic population have quietly urged Caribbeans and those of mixed race to identify themselves simply as black.
"Racial categories as we know them are not going to continue to hold for another 50 to 100 years," says Donna Gabaccia, who heads the University of Minnesota's Immigration History Research Center.
Those who try to keep track of race "are always going to be five or 10 years behind where society is" as race becomes more about choice and less about government definition, adds Mr. Butz of the Population Reference Bureau.
The Melting-Pot Effect
Blacks still cannot jump back and forth across those shifting racial lines, which explains why Sen. Obama calls himself black even while he singled out his white grandmother in his speech claiming the Democratic nomination.
That's not likely to change soon. Some demographers predict that within a century, there will be as many Americans who are mixed-race as there will be those whose parents are both of the same race, further blurring color lines. But that "hybridity," as demographers call it, will be concentrated among Hispanics and Asians who marry whites and each other, not among blacks.
Meanwhile, the definition of who is white may change again -- and again. A century ago, Americans faced the same predictions about the loss of the white majority that they do today. Then, with Eastern and Southern Europeans flooding in, it was predicted that Caucasians would fall into the minority by 1950, says the University of Illinois's Dr. Roediger.
Those Italians, Slavs and other immigrants eventually were redefined as white as they assimilated and moved up the economic ladder. "That same thing could happen again," Dr. Roediger says -- this time, with minorities and immigrants changing their racial identities themselves. "Race is malleable in that sense," he says.