Applying strategic theory to outer space and drawing out the implications for international relations Offers a definitive and original vision of space warfare that theorises often-overlooked aspects of contemporary space activities based in the discipline of Strategic Studies. This original research draws out the implications of spacepower for wider debate in grand strategy and IR. Applies the theory in a topical and contentious area within contemporary grand strategy - anti-access and area-denial warfare in the Taiwan Strait between China and America. Key principles are summarised in seven propositions to make the key take-aways of theory applicable and memorable for researchers and practitioners. This book presents a theory of spacepower and considers the implications of space technology on strategy and international relations. The spectre of space warfare stalks the major powers as outer space increasingly defines geopolitical and military competition. As satellites have become essential for modern warfare, strategists are asking whether the next major war will begin or be decided in outer space. Only strategic theory can explore the decisiveness and effects of war in space upon `grand strategy' and international relations. The author applies the wisdom of military strategy to outer space, and presents a compelling new vision of Earth orbit as a coastline, rather than an open ocean or an extension of airspace as many have assumed. Rooted in the classical military works of Clausewitz, Mahan, and Castex to name a few, this book presents comprehensive principles for strategic thought about space that explain the pervasive and inescapable influence of spacepower on strategy and the changing military balance of the 21st century.