This chapter provides readers with an overview of the book, as well as its major argument. It argues that, while historians have traditionally treated war and military issues as temporary issues that affected American society only during wartime and had little impact on society during peacetime, the issues were, in fact, fundamental to political and cultural changes in American society during the first half of the twentieth century. The chapter also outlines how the remainder of the book will support this argument by focusing on how the relationship formed during this time between national security, education, and the cultural conception of “youth” strongly influenced young people’s educational experiences and had significant social consequences that still exist today.