Cass Sunstein, in the New Yorker (May 3, 2004):

... In September of 1953, just before Brown was to be reargued, [Chief Justice] Vinson died of a heart attack, and everything changed. “This is the first indication that I have ever had that there is a God,” [Justice Felix] Frankfurter told a former law clerk. President Eisenhower replaced Vinson with Earl Warren, then the governor of California, who had extraordinary political skills and personal warmth, along with a deep commitment to social justice. Through a combination of determination, compromise, charm, and intense work with the other justices (including visits to the hospital bed of an ailing Robert Jackson), Warren engineered something that might have seemed impossible the year before: a unanimous opinion overruling Plessy. Thurgood Marshall, a principal architect of the litigation strategy that led to Brown, recalled, “I was so happy I was numb.” He predicted that school segregation would be entirely stamped out within five years.

That’s how Brown looked fifty years ago. Not everyone thinks that it has aged well. Many progressives now argue that its importance has been greatly overstated—that social forces and political pressures, far more than federal judges, were responsible for the demise of segregation. Certainly, Brown has disappointed those who hoped that it would give black Americans equal educational opportunities. Some scholars on the left even question whether Brown was rightly decided. The experience of the past half century suggests that the Court cannot produce social reform on its own, and that judges are unlikely to challenge an established social consensus. But experience has also underlined Brown’s enduring importance. To understand all this, we need to step back a bit.

A quiz: In 1960, on the sixth anniversary of the Brown decision, how many of the 1.4 million African-American children in the Deep South states of Alabama, Georgia, Louisiana, Mississippi, and South Carolina attended racially mixed schools? Answer: Zero. Even in 1964, a decade after Brown, more than ninety-eight per cent of African-American children in the South attended segregated schools. As Klarman shows in his magnificent “From Jim Crow to Civil Rights: The Supreme Court and the Struggle for Racial Equality” (Oxford; $35), the Court, on its own, brought about little desegregation, above all because it lacked the power to overcome local resistance.

Not that it made any unambiguous effort to do so. In the 1954 decision, the Court declined to specify the appropriate remedy for school segregation, asking instead for further arguments about it. The following year, in an opinion known as Brown v. Board of Education II, the Court declared that the transition to integration must occur “with all deliberate speed.” Perhaps fearing that an order for immediate desegregation would result in school closings and violence, the justices held that lower-court judges could certainly consider administrative problems; delays would be acceptable. As Marshall later told the legal historian Dennis Hutchinson, “In 1954, I was delirious. What a victory! I thought I was the smartest lawyer in the entire world. In 1955, I was shattered. They gave us nothing and then told us to work for it. I thought I was the dumbest Negro in the United States.” As a Supreme Court justice, Marshall—for whom I clerked in 1980—liked to say, “I’ve finally figured out what ‘all deliberate speed’ means. It means ‘slow.’”

Real desegregation began only when the democratic process demanded it—through the 1964 Civil Rights Act and aggressive enforcement by the Department of Justice, which threatened to deny federal funds to segregated school systems. But Klarman doesn’t claim that Brown was irrelevant to the desegregation struggle. In his view, the decision catalyzed the passage of civil-rights legislation by, in effect, heightening the contradictions: inspiring Southern blacks to challenge segregation—and Southern whites to defend it—more aggressively than they otherwise would have. Before Brown, he shows, Southern politics was dominated by moderate Democrats, who generally downplayed racial conflicts. The Brown ruling radicalized Southern politics practically overnight, and in a way that has had lasting consequences for American politics....