The United States of America is a federal republic on the North American continent. The United States is the co-leader of the Global Coalition, along with France. It is the most powerful nation in the western hemisphere, with the second-largest GDP in the world. The United States was formed in 1788 following the American Revolution and the global collapse of the British Empire. Consisting of 55 states, the nation also holds two puppet states: the Union of Central America and the Caribbean Federation.