Ronald Reagan's victory in the 1980 presidential election marked a watershed moment in the history of the United States, heralding the triumph of the American conservative movement. Once a supporter of the New Deal, Reagan had come to symbolize the union of three diverse forms of conservatism-anti-communism, social traditionalism, and libertarianism-that were increasingly intertwined under the banner of the Republican Party. The unlikely development of this new conservative coalition was based upon the larger impacts of the civil rights movement in reshaping the dynamics of the Democratic and...