The best I've read wasn't a strategy book per se. 1776 - http://www.amazon.com/1776-David-McCullough/dp/0743226712 by David McCullough was full of useful insights on General George Washington and how he used his smarts to defeat the enemy. He wasn't a great strategist, but very pragmatic (like counting the number of shoes on the feet of his “army’ to asses their battle readiness) and willing to take risks. It book was also entertaining as Hell.