Inside the beltway

A politician, lobbyist, or other person who is politically isolated from the rest of the country, due to the royal court type environment of Washington, DC. Refers to I-495, the beltway around Washington, DC. Could also mean someone who literally lives inside I-495, either in Washington, DC proper or one of the inner suburbs (Arlington, Alexandria, Falls Church City, Bethesda, Chevy Chase, etc)