The Supreme Court’s decision holding unconstitutional a part of the Voting Rights Act (VRA) is one of most symbolically charged decisions in the court’s history.  First enacted in 1965, the part of the law the Court today struck down today—Section 4—was critical in breaking the back of the massive disfranchisement of African-Americans in the South that had been locked into place since the 1890s.  This part of the Act had created a regime wholly unique in American history.  From 1965, those states and local governments that had massively disfranchised these voters could not make any change at all to any aspect of their voting systems—changes as small as the hours polls were open, to changes as big as how election districts for Congress, the state legislature, and local governments were designed—without getting the federal government’s approval in advance.  In essence, this system froze Southern electoral arrangements into place until the federal government approved any changes.  The federal government then sent federal voter registration officials into the South to take over registering voters, and this system began the process of tearing down discriminatory barriers to the vote.

Over the years, Congress remained the key actor.  The question was how long this regime would remain in place and how it would be adapted over time to changing circumstances. . . . 

More here.