Racial GerrymanderingTo the civil-rights community, segregated congressional districts are enlightened public policy. 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...