This book describes a serious look at defending the planet in the event of an extra-terrestrial invasion. Travis Taylor, et al, have written the definitive book on the defense of earth against a potential alien incursion. Whatever your beliefs on the subject, and despite many of my own popular novels I am agnostic at best, the book also serves as an important primer on the potential future of warfare on every level. It is tightly grounded in current day realities of war and extrapolates thoughtfully but closely about future potentials. It should be on the reading list of anyone who is serious about national security and the future of war.