Statement by the President Announcing the Designation of General MacArthur To Lead the Allied Military Forces in Korea
The Security Council of the United Nations in its resolution of July 7, 1950, has recommended that all members providing military forces and other assistance pursuant to the Security Council resolutions of June 25 and 27 make such forces and other assistance available to a unified command under the United States.
The Security Council resolution also requests that the United States designate the commander of such forces, and authorize the unified command at its discretion to use the United Nations flag in the course of operations against the North Korean forces concurrently with the flags of the various nations participating.
I am responding to the recommendation of the Security Council and have designated Gen. Douglas MacArthur as the Commanding General of the military forces which the members of the United Nations place under the unified command of the United States pursuant to the United Nations' assistance to the Republic of Korea in repelling the unprovoked armed attack against it.
I am directing General MacArthur, pursuant to the Security Council resolution, to use the United Nations flag in the course of operations against the North Korean forces concurrently with the flags of the various nations participating.
Harry S Truman, Statement by the President Announcing the Designation of General MacArthur To Lead the Allied Military Forces in Korea Online by Gerhard Peters and John T. Woolley, The American Presidency Project https://www.presidency.ucsb.edu/node/230952