Twentieth Air Force Bombardment Group, remaining at North Field, Guam as its only operational organization. In 1949, budget reductions forced the realignment and consolidation of Air Force units in the pacific, and the mission of Twentieth Air Force became the defense of the Ryukyu Islands and was reassigned to Kadena AB, Okinawa. It commanded the following units: On 27 June 1950, the United Nations Security Council voted to assist the South Koreans in resisting the invasion of their nation by North Korea. President Harry S. Truman authorized General Douglas MacArthur (commander of the US occupying forces in Japan) to commit units to the
United Nations Command members providing military forces and other assistance to South Korea "make such forces and other assistance available to a unified command under the United States of America". President Syngman Rhee of the Republic of Korea assigned operational command of ROK ground, sea, and air forces to General MacArthur as Commander-in-Chief UN Command (CINCUNC) in a letter (the "Pusan Letter") of July 15, 1950: On August 29, 1950, the British Commonwealth's 27th Infantry Brigade arrived at Busan to join UNC ground forces, which until then included only ROK and U.S. forces. The 27th Brigade moved into the Naktong River line west