This path-breaking book reconceptualizes our understanding of political tolerance as well as of its foundations. Previous studies, the authors contend, overemphasized the role of education in explaining the presence of tolerance, while giving insufficient weight to personality and ideological factors. With an innovative methodology for measuring levels of tolerance more accurately, the authors are able to explain why particular groups are targeted and why tolerance is an inherently political concept. Far from abating, the degree of intolerance in America today is probably as great as it ever was; it is the targets of intolerance that have changed. This path-breaking book reconceptualizes our understanding of political tolerance as well as of its foundations. Previous studies, the authors contend, overemphasized the role of education in explaining the presence of tolerance, while giving insufficient weight to personality and ideological factors. With an innovative methodology for measuring levels of tolerance more accurately, the authors are able to explain why particular groups are targeted and why tolerance is an inherently political concept. Far from abating, the degree of intolerance in America today is probably as great as it ever was; it is the targets of intolerance that have changed. George E. Marcus is professor of political science at Williams College and the author, coauthor, or coeditor of seven books, including, most recently, Political Psychology: Neuroscience, Genetics, and Politics .