Why did so many Latin American leftists believe they could replicate the Cuban Revolution in their own countries, and why did so many rightists fear the spread of Communism? Cognitive-psychological insights about people's distorted inferences and skewed interest calculations explain why the left held exaggerated hopes and why the right experienced excessive dread. The resulting polarization provoked a powerful backlash in which the right uniformly defeated the left. To forestall the feared spread of revolution, the military in many countries imposed authoritarian regimes and brutally suppressed left-wingers. Overly worried about the advance of Cuban-inspired radicalism as well, the United States condoned and supported the installation of dictatorship, but Latin American elites took the main initiative in these regressive regime changes. With a large number of primary and secondary sources, this book documents how the misperceptions on both sides of the ideological divide thus played a crucial role in the frequent destruction of democracy. ‘Revolution and Reaction is an excellent book by a leading scholar.’ Scott Mainwaring, Democratization Explains how bold efforts at profound progressive change provoked a powerful reactionary backlash that led to the imposition of brutal, regressive dictatorships. Kurt Weyland utilizes a distinctive theoretical approach that draws on cognitive-psychological insights to elucidate crucial political phenomena. He is the author of four books and approximately fifty journal articles and book chapters. His previous book about waves of democratization, Making Waves, (Cambridge, 2014), won the book award from American Political Science Association's Comparative Democratization section.