A superpower's a state with a leading position in the international system and the ability to influence events and its own interests and project power on a worldwide scale to protect those interests; it's traditionally considered to be one step higher than a great power. Alice Lyman Miller (Professor of National Security Affairs at the Naval Postgraduate School), defines a superpower as "a country that's the capacity to project dominating power and influence anywhere in the world, and sometimes… (More on Superpower)