The term LEADER AT POTSDAM is referring to Joseph Stalin, the leader of the Soviet Union who attended the Potsdam Conference in 1945. The Potsdam Conference was a meeting between the Allied powers of World War II, including the United States, the United Kingdom, and the Soviet Union. At this conference, the leaders discussed the post-war reorganization of Germany and other issues related to the war. Stalin's presence at the conference was significant as it marked the beginning of the Cold War between the Soviet Union and the Western Allies.