This chapter introduces the study and sets out a framework for investigating counterinsurgency’s intellectual history. I argue late twentieth and early twenty-first century counterinsurgency is a form of conservative, high modern utopianism. It is conservative in aiming to protect a given status quo against revolution or other transformative change. Counterinsurgency is “high modernist” in James C. Scott’s sense: it imagines a linear, schematized world, effacing local difference and resistance—in line with modern ideologies of progress. It is utopian in aiming to (re)make not actually existing systems and practices, but instead the idealized preferences of their elites, shorn of compromise, incidental variation, and historical specificity. Counterinsurgencies are thus conservative worldmaking projects: attempts to reimagine and reorder the world, in response to insurrection. The book’s purpose is the explain how this configuration of armed politics arose. To do so, it focuses on counterinsurgency manuals: the military theoretical and instructional texts designed to make counterinsurgency doable in practice.