Blacks should know their place, the media seem to think. Increasingly, they are leaving their natural habitat — the inner city — and wandering into residential areas where lots of non-blacks live, the Washington Post and other media outlets report with obvious distress. The black population is shrinking in urban congressional districts and swelling in suburban ones, they note. Indeed, looking at the newest census numbers, the 15 districts with the greatest black-population growth are all in the suburbs. Conversely, the African American population in eight of the top ten majority-black districts dropped by an average of more than 10 percent. There goes the neighborhood — that is, the black ghetto. It isn’t yet gone, but it’s going.

One might see that as excellent news. It’s not, the mainstream media tell us. Residential segregation has long been considered the most important sign of miles to go on the road to racial equality, but the escape of blacks to the suburbs will make the creation of majority-black legislative districts harder to achieve. And yet such districts are essential to the integration of black politics, the conventional wisdom runs. Racial fairness makes them mandatory, those who interpret and enforce the 1965 Voting Rights Act have long believed. Where demography is not propitious, the statute demands that, to the extent possible, state legislators draw gerrymandered districting lines to ensure safe black seats in numbers proportionate to the minority population. But if blacks keep scattering, as they are doing, black representation by black officeholders will inevitably become harder to ensure.

A possible Justice Department response to the new, worrisome demographic picture is to insist on even more imaginative racial gerrymandering to recapture black voters who have fled cities for greener pastures, but a majority on the Supreme Court has voiced dismay over tortured race-driven lines. The Court’s discomfort arises from constitutional concerns, but quite another question can also be asked: When black voters have been able to choose the traditional path of upward mobility and settle in a suburb, should the law be working to reunite those voters with the communities they made great efforts to escape?

It seems legitimate to assume (although I know of no survey data confirming the point) that minority families who leave central cities don’t necessarily identify with their former, less prosperous neighborhoods. Surely, they acquire new interests tied to schools, as well as other institutions and organizations in the area where they now live. And thus we may wonder why legislators drawing new maps insist on stereotyping blacks as fungible members of a cohesive group and, on the basis of that assumption, place them in bizarre districts that often resemble (as one federal judge has put it) “a microscopic view of a new strain of disease.”

The media have been treating the residential dispersion of black voters as another American racial tragedy in the making. From a number of perspectives this is an odd view. It ignores some basic history. The mass migration of blacks to northern cities a century ago created the black ghettos, and their racial isolation increased as their numbers expanded dramatically in the years from World War I to the 1960s. But the movement of African Americans to the suburbs is no recent phenomenon; it began four decades ago.

This powerful trend has been recently accelerating, the newly released 2010 census data show. In the first decade of the new century, residential segregation (by the standard measure) dropped in 92 of the 100 largest metropolitan areas. Heavily black neighborhoods have not disappeared, but the typical African American today lives in a census tract in which blacks are not an actual majority.

Both in cities and in suburbs, America is thus becoming increasingly multi-ethnic — a picture we should surely celebrate. And yet, while residential segregation is widely viewed as evidence of continuing racial pathology, the deliberate drawing of electoral districts to segregate whites from minorities is, ironically, considered positively enlightened public policy.

It is not, in fact. Race-conscious districts, particularly in the South, were appropriate in the years in which few southern whites would vote for black candidates regardless of their qualifications. But they come with substantial costs that are bound to grow as America keeps maturing racially. By now, those costs outweigh any possible benefits.

Separating voters on the basis of race, Justice O’Connor wrote in 1993, threatens “to stigmatize individuals by reason of their membership in a racial group.” Black spokesmen themselves often talk about African Americans as a racially defined group apart. If you’re black, you “share common values,” the NAACP’s Hilary Shelton recently said. And of course Jesse Jackson memorably stated in 2009, “You can’t vote against health care and call yourself a black man.” Do we really want statutorily mandated districting maps that reinforce the black-nationalist notion that ethnic groups each have their own distinctive culture?

Cass Sunstein — a Harvard law professor currently on leave to serve the president — has identified a related problem. Across the political spectrum, Sunstein has argued, when people talk only with those who are of like mind, they end up with more extreme views than they would hold otherwise. The point can be logically extended: Most voters in a district drawn for the sole purpose of maximizing black representation will generally talk politics only with people who share their left-leaning, race-conscious values. And aspiring politicians who seek office in such settings have every incentive to run on their racial identity — defining themselves as “authentically” black. “Post-racial” has no appeal in such contexts, with the result that very few members of the Congressional Black Caucus have a voting record that would attract white support, except in reliably liberal jurisdictions.

Members of the CBC who won their seats in majority-black districts by defining themselves as racially authentic have acquired secure seats but no experience building biracial coalitions. Thus, they’ve been traveling on a road going nowhere. In 2000, incumbent Bobby Rush handily defeated challenger Barack Obama for a seat in the U.S. House of Representatives by emphasizing his racial bona fides, his commitment to representing black interests, and his leftist politics. Imagine if Obama had managed to defeat Rush. As one more member of the Congressional Black Caucus (which won’t even admit a white elected from a majority-black district), he would most likely have found the presidency an impossible dream.

The majority-black districts to which the civil-rights community and its allies in the media and the academy are so committed also appear to act as a brake on black political participation. A number of first-rate scholars have found that safe black districts dampen electoral turnout; why bother to vote when the outcome will surely be the election of one black candidate or another — all likely to support the same policies once in office? In addition, racially gerrymandered lines that wander all over the landscape may bring black families under one majority-black political roof, but they make organized political activity more difficult. A townwide civic organization, for instance, will find it harder to campaign for an issue or candidate if it has to mobilize in separate congressional districts arbitrarily drawn to further black officeholding.

In 2011, does black political inclusion really still depend on protecting black candidates from white competition in race-based districts? When black families pursue the American dream and move from city to suburb, do they need to be kept in their old majority-black congressional district? Once upon a time, treating all blacks as members of a “community” made sense; white racism obliterated social class and other distinctions. But today? Is real racial progress a figment of the conservatives’ misguided imagination?

“An American dilemma,” Gunnar Myrdal once called race in America. The phrase has stuck, but it’s dated. An American muddle would be more accurate. Why can’t we think straight about the nation’s most important domestic issue?

— Abigail Thernstrom is the author, most recently, of Voting Rights — and Wrongs: The Elusive Quest for Racially Fair Elections. She is an adjunct scholar at the American Enterprise Institute and vice chair of the U.S. Commission on Civil Rights.