Politics in America are polarized and trivialized, perhaps as never before. In Congress, the media, and academic debate, opponents from right and left, the Red and the Blue, struggle against one another as if politics were contact sports played to the shouts of cheerleaders. The result, Ronald Dworkin writes, is a deeply depressing political culture, as ill equipped for the perennial challenge of achieving social justice as for the emerging threats of terrorism. Can the hope for change be realized? Dworkin, one the world's leading legal and political philosophers, identifies and defends...