Chapters 15 through 30: Vol. 2Over a century ago, the rapid expansion of global overseas trade brought about by the advent of improved steam propulsion and advances in ship design and construction posed new national policy and security questions for the United States. First, to what degree did American economic prosperity depend upon being a major active participant in maritime commerce? Second, what were the naval implications of such action with respect to the extension and defense of important, if not vital, American interests? Third, what role should the U.S. Government play in the promotion of maritime commercial activity andthe creation of the naval forces required to protect American overseas trade? And fourth, what changes, if any, were required with respect to the direction of American foreign policy? In 1890, Captain Alfred Thayer Mahan, a serving officer in the U.S. Navy, published The Influence of Sea Power upon History, 1660-1783. This book provided a comprehensive statement about maritime commerce, naval power, government policy, and international politics that became the theoretical point of departure for almost all discussion of what was widely regarded to be the most important national security problem of the day, both in the United States and around the world.Today, the importance of space as a venue for economic and military activity in certain respects resembles the conditions of maritime commerce and naval power in the late 19th century. These circumstances prompt two questions: first, is a history-based exploration of prospects and possibilities of spacepower, in the manner of Mahan, a viable intellectual proposition? Second, does his work contain ideas that are applicable to spacepower or at least suggest potentially productive lines of inquiry? Addressing theseissues, however, requires a sound foundation-namely, an accurate understanding of Mahan's major arguments and his manner of reasoning. Unfortunately, misunderstanding Mahan is the rule rather than the exception. His writing is rarely read, and the bulk of the critical literature is corrupted by serious interpretive error. What follows is a schematic representation of Mahanian argument that can be related to the consideration of thenature of the theoretical problem of space-power.