The attack upon Korea was an outright breach of the peace and a violation of the Charter of the United Nations. By their actions in Korea, Communist leaders have demonstrated their contempt for the basic moral principles on which the United Nations is founded. This is a direct challenge to the efforts of the free nations to build the kind of world in which men can live in freedom and peace.

Harry S. Truman: Containing the Public Messages, Speeches, and Statements of the President, 1945-53 (ed. 1961)