You sound like you're looking for something like Jones' The Art of War in the Western World: http://www.amazon.com/Art-War-Western-World/dp/0252069668 Or just go there and follow Amazon "related" links. Jones is of the "very broad" school of military history. It can be a little bit dry, but it certainly tries to be comprehensive: It's like Civilization in that it starts with phalanx and then moves slowly forward through the history of strategy and tactics. You might like the works of John Keegan, another famous military historian who takes a general approach. He's got a History of Warfare that's like a lighter-weight version of Jones -- I might recommend starting with that, actually. His one-volume histories of WWI and WWII are probably decent.…
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