Balance of power is one of the most enduring concepts in international relations theory. Books have been penned on the subject, articles written, debates held. Scholars foundational to the fi eld have argued that the balance of power is the fundamental dynamic of global aff airs (Morgenthau 1985). Some have argued for the superiority of a particular balance of power over others (Waltz 1979). Still others have called into question whether there really is a balance of power at all, or whether the concept has any power to help understand world aff airs (Nogee 1975; Rosecrance 2003). Despite the ongoing debates about scope conditions and defi nitions, there is widespread acceptance of the notion that the balance of power in the international system has signifi cant eff ects on a state’s foreign policy.