America's modern struggle with race has proceeded on three fronts. The legal battle effectively ended a half-century ago with the Civil Rights Act of 1964. The second front, the battle against private prejudice, has not been won so decisively, but the experiences of Cliven Bundy and Donald Sterling in the past few weeks confirm a longstanding truth about American society: Expressions of racial prejudice by public figures are punished swiftly and severely.

The third front is different in kind. This campaign is waged not against...