"What is new about the emerging world order is that, for the first time, the United States can neither withdraw from the world nor dominate it. America cannot change the way it has perceived its role throughout its history, nor should it want to. When America entered the international arena, it was young and robust and had the power to make the world conform to its vision of international relations. By the end of the Second World War in 1945, the United States was so powerful (at one point about 35 percent of the world’s entire economic production was American) that it seemed as if it was destined to shape the world according to its preferences. John F. Kennedy declared confidently in 1961 that America was strong enough to “pay any price, bear any burden” to ensure the success of liberty. Three decades later, the United States is in less of a position to insist on the immediate realization of all its desires. Other countries have grown into Great Power status. The United States now faces the challenge of reaching its goals in stages, each of which is an amalgam of American values and geopolitical necessities. One of the new necessities is that a world comprising several states of comparable strength must base its order on some concept of equilibrium— an idea with which the United States has never felt comfortable."