The Voting Rights Act of 1965 was the crowning achievement of the civil rights movement in the 1960s. Applying primarily to six Southern states, it suspended the literacy tests and other devices used to exclude black voters, empowered federal examiners to help with registration and required the states to get Justice Department approval of changes in voting regulations. The results have been impressive: 3.5 million blacks are registered in the South today, compared with 1 million in 1965. The number of Southern blacks holding elected office has jumped 2,000% to nearly 1,600.
Still, there is much room for improvement. Only 2%...