At her best, popular historian Tuchman tells a good story. At her worst, she can be superficial and banal. An exercise in historical interpretation such as this, tracing a single idea through a set of examples, is structured toward her weaknesses; and they are only too apparent. Tuchman applies the concept of folly to historical "mistakes" with certain features in common: the policy taken was contrary to self-interest; it was not that of an individual (attributable to the individual's character), but that of a group; it was not the only policy available; and it was pursued despite forebodings that it was mistaken. The only way to account for such self-destructive policies, in Tuchman's view, is to label them follies; but that, as she seems unaware, puts them beyond rational explanation. Her three major examples are the aggressive actions of the Renaissance popes that resulted in the Reformation, Britain's loss of the American colonies, and the American debacle in Vietnam. (The Trojan Horse episode serves as an introductory prototype.) One of Tuchman's auxiliary categories is "wooden-headed," which is what she calls the popes who resisted pleas for reform, stuck to their doomed ways, and otherwise lived debauched lives. (On the other hand, "Kennedy was no wooden head," since he avoided making a decision on Vietnam; had he lived, he would presumably either have withdrawn from Vietnam or become another wooden head.) Disavowals notwithstanding, Tuchman cannot escape exercising hindsight. The appearance is inescapable that she has plumbed her cited sources not for their evocation of the mentality of an age but for some good quotes that support the contention of available alternatives. On the American Revolution, for example, her simple account of the Stamp Act and parliamentary debate on the colonies betrays no substantial knowledge of the recent, careful reconstruction of the political understandings of the time. While Tuchman's gaze is squarely fixed on ministers in London trying to implement an unenforceable tax, the real dynamics of colonial rebellion were being played out in America. If there was folly here it was the same as Tuchman's, lying in the ignored political transformation across the ocean. None of the sections work as straight narrative: they are too shallow, and the time covered is too long, for more than an outline of events. Unable to explain the courses of action taken, Tuchman cries folly. That principle of historical interpretation is likely to satisfy very few.