Louis Arthur Johnson was a prominent American politician and attorney who served as the second United States Secretary of Defense. He held this position from 1949 to 1950 under President Harry S. Truman, overseeing the military during the early stages of the Cold War. Prior to this, he was the national commander of the American Legion and served as Assistant Secretary of War from 1937 to 1940. His tenure as Secretary of Defense was marked by significant budget cuts to the military, which became highly controversial with the outbreak of the Korean War.