Ladwig provides a rewarding theory-driven account of US counter-insurgency in the Philippines, Vietnam before 1963 and El Salvador. He draws interesting conclusions about the value of conditionality in aid, and argues it is the only effective means of generating influence. This book is deeply unsatisfying, however, because it mis-applies principal-agent theory. The idea that US allies, which are sovereign states, are "agents" of American power within their own territory is simply colonialist, and moreover does not really describe Ladwig's cases (the US was never an occupying, sovereign power in any of them). Nonetheless, Ladwig declares America the "principal" without explaining why. To Ladwig, perhaps it is self-evident that the Western "great power" (to use his phrase) is the key actor and its objectives are paramount, especially from Ladwig's "policy" perspective. In fact, its probably better said that the USG is functionally one of several agents of the host nation governments in all the cases Ladwig addresses.