Morganthau is a good start. But if I understand your interest correctly, I think you also might want to look into Games Theory. I'd recommend The Strategy of Conflict by Thomas C. Schelling. Of particular interest, and a topic not generally covered well (if they even admit its existence) in poli sci, is the concept of the irrational player. i.e. "One of us has to be reasonable, and it won't be me."

More to follow.