Even though Latin American militaries have over the last decade retreated into their barracks, understanding their formation, historic role, internal politics, and self-perception remains important. It is, curiously, American scholars who have made the major contributions to this field, and now McCann has produced a magnificent, detailed, comprehensive tome on Brazil's army, based on a lifetime of study. The great strength of McCann's book is that he aims to see the army from the inside out, in terms of its internal dynamics and powerful figures. He argues that, in the period covered, the military was Brazil's only "national" institution and stood at the core of the developing Brazilian state. The officer corps, in contrast to other Brazilian elites, was nationalist both by definition and by constitutional mandate. In the 1920s, internal rebellion and social change threatened the army's cohesion, but the institution reinvented itself in the 1930s, when it played a critical role in establishing the dictatorship of Getulio Vargas. Such experiences, McCann demonstrates, do much to explain the attitudes of the officers who ruled Brazil from 1964 to 1985.