A good book on American history for the last 20 years?

http://www.amazon.com/American-Foreign-Policy-New-Era/dp/0415951003/ref=sr_1_37?s=books&ie=UTF8&qid=1286394359&sr=1-37

Given your parameters, any book by Andrew Bacevich. West Point grad and a poignant observer on American military policy over the last 20 years. Focuses on the relationship between politics and foreign policy, particularly as it pertains to use of military. Thoughtful guy, with a slight bias (his son died in Iraq) but with an important opinion. As a veteran myself, I do not agree with everything he says, but definitely worth listening to.

Ghost Wars