(Bill O’Leary/The Washington Post)

When I was growing up in Orangeburg, S.C., the white power structure found a clever way to keep African Americans from having a say in municipal affairs: They engineered the city’s boundaries, annexing white subdivisions but not black ones, so that whites would retain a majority — and blacks would remain, essentially, unrepresented.

Today, a 5 to 4 majority of the Supreme Court shamefully weakened the 1965 Voting Rights Act. Chief Justice John Roberts led the court’s conservative wing in stripping the act of its most effective enforcement tool.

The court is, of course, right in one observation: These days, attempts to disenfranchise African Americans and other minorities are not limited to the South. Burdensome voter ID laws and other restrictions are being imposed in states such as Ohio, Pennsylvania and Arizona. And yes, there are scads of black elected officials in Mississippi.

But most violations of the Voting Rights Act still take place in the states of the old Confederacy. The solution should have been to expand the map of jurisdictions required to seek pre-clearance from the federal government for changes in election laws — rather than erase the map altogether.

I could not be more pessimistic about the prospect that Congress will come up with a new formula and a new map.The rest of the act remains in effect, but we may have to live with the fact that now it will be more difficult to enforce.

But I can’t help but be optimistic in the long term. In last year’s presidential election, black turnout was actually higher than white turnout. Latinos and Asian-Americans, too, continue their rise as powerful voting blocs. The ascendancy of previously underrepresented minorities as full participants in U.S. democracy is a secular trend, and no five men in robes can hold it back.