In times of crisis—and who can doubt that we are living in one now?—political people ask themselves whether they are about to witness a dramatic ideological realignment and, if so, whether the reconfiguration of the left-to-right spectrum of U.S. electoral contests opens up new possibilities for themselves and the issues that motivate them. We are currently undergoing a major realignment, perhaps as significant as the one that began in World War I and culminated with the 1932 election of FDR and the status quo that Americans have lived with all their lives. In that earlier shift, Democrats abandoned their conservativism and became a liberal coalition of working-class people, labor unions, ethnic minorities, and marginalized identity groups, while Republicans embraced big business, libertarianism, and an aggressive, militaristic, materialistic posture toward foreign policy. In the years following the 9/11 attacks, who could have imagined that—at least in their rhetoric and campaigning, if not in actual governance—Republicans would identify themselves as isolationists and…