This introduction presents an overview of the key concepts discussed in the subsequent chapters of this book. The book examines how economic transformation in the United States and the nation's changing role in the global economy factored into the decision to wage war on Spain. It discusses the economic, political, and legal changes enacted by the military governments in Puerto Rico. The book also discusses some of the economic forces and strategic considerations that influenced the formation of colonial policy for Puerto Rico, as well as the other territorial possessions. It also examines the logic and properties of the colonial state that Congress developed and imposed on Puerto Rico. The book investigates how the very process of institutional and economic transformation engendered new complexities that complicated the task of colonial management. It describes the Federacion Libre de Trabajadores and the Socialist Party.