"Territorial expansion was the foundation of American power and greatness. From the beginning of history to the present time, no country ever exerted a controlling power over the world until it had acquired a wide extent of territory." - William R. Garrett.

The Constitution of Empire offers a constitutional and historical survey of American territorial expansion from the founding era to the present day. The authors describe the Constitution’s design for territorial acquisition and governance and examine the ways in which practice over the past two hundred years has diverged from that original vision. Noting that most of America’s territorial acquisitions—including the Louisiana Purchase, the Alaska Purchase, and the territory acquired after the Mexican-American and Spanish-American Wars—resulted from treaties, the authors elaborate a Jeffersonian-based theory of the federal treaty power and assess American territorial acquisitions from this perspective. They find that at least one American acquisition of territory and many of the basic institutions of territorial governance have no constitutional foundation, and they explore the often-strange paths that constitutional law has traveled to permit such deviations from the Constitution’s original meaning.

The Bush Administration has notoriously argued that detainees at Guantanamo do not enjoy constitutional rights because they are held outside American borders. But where do rules about territorial legal limits such as this one come from? Why does geography make a difference for what legal rules apply? Most people intuitively understand that location affects constitutional rights, but the legal and political basis for territorial jurisdiction is poorly understood. In this novel and accessible treatment of territoriality in American law and foreign policy, Kal Raustiala begins by tracing the history of the subject from its origins in post-revolutionary America to the Indian wars and overseas imperialism of the 19th century. He then takes the reader through the Cold War and the globalization era before closing with a powerful explanation of America's attempt to increase its extraterritorial power in the post-9/11 world. As American power has grown, our understanding of extraterritorial legal rights has expanded too, and Raustiala illuminates why America's assumptions about sovereignty and territory have changed. Throughout, he focuses on how the legal limits of territorial sovereignty have diminished to accommodate the expanding American empire, and addresses how such limits ought&R to look in the wake of Iraq, Afghanistan, and the war on terror. A timely and engaging narrative, Does the Constitution Follow the Flag? will change how we think about American territory, American law, and-ultimately-the changing nature of American power.