section_path: Government and politics
section_name: Government and politics
paragraph_text: Government and politics
  
  The United States is a federal republic of 50 states and a federal capital district, Washington, D.C. The U.S. asserts sovereignty over five unincorporated territories and several uninhabited island possessions. It is the world's oldest surviving federation, and its presidential system of national government has been adopted, in whole or in part, by many newly independent states worldwide following their decolonization. The Constitution of the United States serves as the country's supreme legal document. Most scholars describe the United States as a liberal democracy.