"The "national interest" is not a geographical term, except for fairly prosaic matters like trade and environmental regulation. A smaller nation might appropriately feel that its national interest begins and ends at its borders, so that its foreign policy is almost always in a defensive mode. A larger nation has more extensive interests. And large nations, whose identity is ideological, like the Soviet Union of yesteryear and the United States of today, inevitably have ideological interests in addition to more material concerns... No complicated geopolitical calculations of national interest are necessary."