IN THE MAIL: (Actually, something I ordered for a project I’m working on). Travis S. Taylor et al.‘s book, An Introduction to Planetary Defense: A Study of Modern Warfare Applied to Extra-Terrestrial Invasion.
I had an interesting discussion on this topic with some NORAD guys when I spoke at the Air Force Academy several years ago. The book looks okay, but not as focused as I’d hoped — though admittedly the topic itself is pretty unfocused. The Amazon reader reviews are good.