Here's something interesting on Google Books; it's titled Military Geography for Professionals and the Public, written by a US Army colonel named John Collins in 1998. Here's a review. Excellent basic stuff, full of things you've never thought of (check out the chapter on war in space), though 1) it's riddled with typos, poorly edited, and includes several words used with the wrong meaning and 2) the basic ideas in the human geography chapter are good, but a lot of the examples are lousy and a few are incorrect. I could fix this thing in ten hours, and they should have paid somebody like me to do so before publishing it.

They want sixty bucks at Amazon for a print copy of this.