This is a thought-provoking book written at what might be viewed as the intersection of political theory, jurisprudence and international relations. The author, a law professor at Yale, makes an important distinction between the traditional "horizontal" approach to international law, in which states are coequal actors, and the "vertical" approach, which is dependent upon the relationship between the state and the individual. The latter, she argues, raises the question of legitimacy. Hence, a state's actions outside its borders must be evaluated in terms of the justification that grants the state the right to operate domestically. The reader is forced to think afresh. Were this reinterpretation of international law ever to be widely accepted, it would transform concepts such as the right of intervention and just war.