the leader of the free world
1. The United States of America, especially in relation to international politics. (Sometimes capitalized.) Ever since the Cold War, America has prided itself on being known as the Leader of the Free World. Some people feel that our country has a responsibility, as the leader of the free world, to help shape the way countries across the globe do business.
2. By extension, the President of the United States of America. (Sometimes capitalized.) Since he was a young boy, Gerald had dreamed of someday becoming the leader of the free world.