United Nations Command operates under the mandates of UN Security Council Resolutions 82, 83, and 84. While the UN had some military authority through Chapter VII of the United Nations Charter, Cold War tensions meant that the forces envisaged in those articles had never become reality. Thus the UN had little practical ability to raise a military force in response to the North Korean invasion of the South. Consequently, the UN Security Council designated the United States as the executive agent for leading a "unified command" under the UN flag. As such, the United Nations exercised no control over the combat forces. However, as this represented one of the first attempts at collective security under the UN system, UN leadership maintained a close relationship with UN Command during the war and for years after hostilities ceased.