Franklin D. Roosevelt and his colleagues expected the United States to emerge from the postwar as the greatest power on earth. And after this war, unlike the aftermath of World War I, they were determined to assert American leadership. The apotheosis of the American-vision emerged from the Bretton Woods Conference of 1944. The principal goal at Bretton Woods was the creation of mechanisms for assuring stable-exchange rates. Indeed, Chiang Kai-shek, the Chinese-leader, to the irritation of the Americans, had posted half a million of his best-equipped forces as a barrier to Communist-expansion rather than risk those assets against the Japanese. Roosevelt died and Harry S. Truman became the thirty-third president of the United States. In 1945, Truman went to Potsdam where, amid the ruins of Hitler's Reich, he met with Churchill and Stalin in the last major conference of the war. Truman set sail for home, ordered atom bombs dropped on Hiroshima and Nagasaki, and World War II was over.