34 p. The United States has maintained its superpower status since the end of World War II. Today in a unipolar world, its preponderance is often akin to the greatness of the ancient Roman Empire.1 It enjoys natural geographical advantages and remains politically, economically and militarily superior. Its military expenditure alone accounts for 50 percent of total world military spending.2 In 2007, the United States is also estimated to be operating over 700 military bases around the world Master of Science (International Relations)