“Totalitarianism” is a powerful word rich in historical associations and rebounding in current political usage. The four books under review reflect both the term's range of usage and the enduring fascination with the phenomena it described. Totalitarianism's initial terminological siblings, “nazism” and “communism,” are applied chiefly to the original historical subjects that generated them. A close political cousin, “fascism,” long ago escaped its close ideological family and is applied to everything from brutal police to road hogs. In contrast, “totalitarianism,” formerly confined to a narrow political as opposed to a cultural context, is suddenly in play. In recent issues of the New York Times, David Brooks excoriates Iraqi proponents of “totalitarian theocracy” (5/16/2004); President Bush deplores the terrorists’ “totalitarian ideology” (5/29/05), and Condoleezza Rice abhors Iran as a “totalitarian state” (5/29/2005). A Central Asian despot is characterized as a “fragile totalitarian” in a feature by David E. Sangler (5/29/2005), and the group of army officers (the Military Council for Justice and Democracy) that overthrew President Maouya Sidi Ahmed Taya in Mauritania in August 2005 defend their decision “to put an end to the totalitarian practices of the deposed regime.” Totalitarianism is back, but what does it mean?