United Nations Command

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.

When the warring parties signed the Korean Armistice Agreement on July 27, 1953, the UNC delivered the Agreement to the United Nations. In August 1953, the United Nations General Assembly passed a resolution “noting with approval” the Armistice Agreement, a step that was critical for the UN to take the next step of organizing the 1954 Geneva Conference meant to negotiate a diplomatic peace between North and South Korea. The adoption of the Korean Armistice Agreement in the General Assembly underwrites UN Command's current role of maintaining and enforcing the Armistice Agreement.

The role of the United States as the executive agent for the unified command has led to questions over its continued validity. Most notably, in 1994, UN Secretary General Boutros Boutros-Ghali wrote in a letter to the North Korean Foreign Minister that:

the Security Council did not establish the unified command as a subsidiary organ under its control, but merely recommended the creation of such a command, specifying that it be under the authority of the United States. Therefore the dissolution of the unified command does not fall within the responsibility of any United Nations organ but is a matter within the competence of the Government of the United States.[8]

The UN's official position is that the Korean War-era Security Council and General Assembly resolutions remain in force. This was evidenced in 2013 when North Korea announced unilateral abrogation of the Armistice Agreement: UN spokesman Martin Nesirky asserted that since the Armistice Agreement had been adopted by the General Assembly, no single party could dissolve it unilaterally. The UNC continues to serve as the signatory and party of the Armistice opposite the Korean People's Army.

After troops of North Korea invaded South Korea on 25 June 1950, the United Nations Security Council adopted Resolution 82 calling on North Korea to cease hostilities and withdraw to the 38th parallel.[9]

Two days later, the UNSC adopted Resolution 83, recommending that members of the United Nations provide assistance to the Republic of Korea "to repel the armed attack and to restore international peace and security to the area".[10]

The first non-Korean and non-U.S. unit to see combat was the No. 77 Squadron of the Royal Australian Air Force, which began escort, patrol and ground attack sorties from Iwakuni, Japan on 2 July 1950. On 29 June 1950, New Zealand made preparations to dispatch two Loch class frigates,Tutira and Pukaki, to Korean waters;[11] on 3 July, the ships left Devonport Naval Base, Auckland and joined other Commonwealth forces at Sasebo, Japan on 2 August. For the duration of the war, at least two NZ vessels would be on station in the theater.

Resolution 84, adopted on 7 July 1950, recommended that 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".[12]

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) on 15 July 1950:

In view of the common military effort of the United Nations on behalf of the Republic of Korea, in which all military forces, land, sea and air, of all the United Nations fighting in or near Korea have been placed under your operational command, and in which you have been designated Supreme Commander United Nations Forces, I am happy to assign to you command authority over all land, sea, and air forces of the Republic of Korea during the period of the continuation of the present state of hostilities, such command to be exercised either by you personally or by such military commander or commanders to whom you may delegate the exercise of this authority within Korea or in adjacent seas.[13]

On 29 August 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 of Daegu.

Units from other countries of the UN followed: the Belgian United Nations Command, the 25th Canadian Infantry Brigade, the Colombian Battalion,[14] the Ethiopian Kagnew Battalion, the French Battalion, the Greek 15th Infantry Regiment, New Zealand's 16th Field Regiment and Royal New Zealand Artillery, the Philippine Expeditionary Forces to Korea, the South African No. 2 Squadron SAAF, the Turkish Brigade, and forces from Luxembourg and the Netherlands. Additionally, Denmark, India, Iran, Norway and Sweden provided medical units; Italy provided a hospital, even though it was not a UN member.

By 1 September 1950, less than two months before the formation of United Nations Command, these combined forces numbered 180,000, of which 92,000 were South Koreans, with most of the remainder being comprised of Americans followed by the 1,600-man British 27th Infantry Brigade.

During the three years of the Korean War, the following nations were members of the UNC.[15] On 27 July 1953, the day the Armistice Agreement was signed, UNC reached a peak strength of 932,964:

• Combat forces
  • South Korea – 590,911
  • United States – 302,483
  • Canada – 26,791
  • Australia – 17,000
  • United Kingdom – 14,198
  • Thailand – 6,326
  • Ethiopia – 6,007
  • Turkey – 5,453
  • Philippines – 1,468
  • New Zealand – 1,385
  • Greece – 1,263
  • France – 1,119
  • Colombia – 1,068
  • Belgium – 900
  • South Africa – 826
  • Netherlands – 819
  • Luxembourg – 44
• Humanitarian aid (not counted in total above)
  • Denmark (hospital ship MS Jutlandia) – 600
  • India
  • Italy (68th Field Hospital) – 71[16]
  • Norway (NORMASH)
  • Sweden

During the course of the war, UNC was led by Douglas MacArthur, Matthew B. Ridgway, and Mark Wayne Clark. After the armistice was signed, John E. Hull was named UNC commander to carry out the ceasefire (including the voluntary repatriation of prisoners of war).[17]

Following the signing of the Armistice Agreement, UNC remained in Korea to fulfill the functions of providing security and stability on the Peninsula, as well as supporting UN efforts to rebuild the war-torn Republic of Korea. Much of the fifties was marked by continuous negotiations in Military Armistice Commission meetings while the international community worked to bolster South Korea's economy and infrastructure. During this period, North Korea maintained economic and military superiority over its southern neighbor owing to Chinese and Soviet support.

The sixties proved a tenuous decade on the Korean Peninsula, punctuated by a period of hostilities often referred to as the "Second Korean War." The period between 1966 and 1969 saw a heightened level of skirmishes in the DMZ as well as major incidents including North Korea's attempted assassination of South Korean leader Park Chung-hee and seizure of the USS Pueblo.

The seventies saw a brief period of rapprochement that later contributed to structural changes to UNC. In 1972, the North and South Korean governments signed a Joint Communique calling for more peaceful ties between the two Koreas. Concurrently, consecutive U.S. administrations (Nixon, Ford, and Carter) sought to decrease the South Korean reliance upon U.S. forces for maintaining deterrent capabilities on the Korean Peninsula. On 7 November 1978 a combined headquarters, the Republic of Korea – United States Combined Forces Command (CFC), was created, and the South Korean military units with front-line missions were transferred from the UN Command to the CFC's operational control. The commander-in-chief of the CFC, a United States military officer, answered ultimately to the national command authorities of the United States and that of South Korea.

From 1978, UNC maintained its primary functions of maintaining and enforcing the Korean Armistice Agreement, facilitating diplomacy that could support a lasting peace on the Peninsula, and providing a command that could facilitate multinational contributions should the armistice fail. UNC decreased in size, and over time, many of the billets assigned to UNC became multi-hatted with U.S. Forces Korea and Combined Forces Command.

The 1990s again saw notable change in UNC. In October 1991, UNC transferred responsibility of all DMZ sectors except for the Joint Security Area to the ROK military. In 1992, UNC appointed a South Korean General officer to serve as the Senior Member to the Military Armistice Commission. This led to the Korean People's Army and Chinese People's Volunteers boycotting MAC meetings. The collapse of the Soviet Union also led North Korea to question the alignment of their choices for the Neutral Nations Supervisory Commission. They no longer recognized Czech or Slovak representatives when Czechoslovakia when the nation split into the Czech Republic and Slovakia, and North Korea expelled the Polish delegation in 1994. Also in 1994, North Korea dismissed the Chinese People's Volunteers from the Panmunjom mission, owing in part to their protest over China's warming ties with South Korea.

Since 1998, UNC has seen a gradual increase of permanent international staff within the command. In between 1998 and 2003, several of the original contributors to the Korean War began deploying personnel to Korea to support UNC's armistice maintenance functions. This internationalization has continued over the next decades. In May 2018,[18] Canadian Lt. General Wayne Eyre became the first non-American to serve as deputy commander of the UNC.[18][19][20][21] Succeeding him was Australian Vice Admiral Stuart Mayer, continuing the trend of non-American leadership in UNC.

To further the September 2018 inter-Korean Comprehensive Military Agreement, UN Command, Republic of Korea Armed Forces, and North Korean People's Army officials met in a series of negotiations to deliberate the demilitarization of the Joint Security Area. The first two meetings in October led to Demining activities within the JSA, de-arming of personnel, and sealing off of Guard Posts. On November 6, 2018, UNC conducted a third round of negotiations with the South Korean military and North Korean People's Army on "Rules of Interaction" which would underwrite a Joint Security Area where both sides of the Military Demarcation Line—the de facto border—would be open to personnel. For undisclosed reasons, the North Korean side refused to meet to finalize these rules and the next step for realizing a demilitarized Joint Security Area.

• United Nations Memorial Cemetery in Busan, where 2,300 casualties from various nations are buried

• Grey, Jeffrey. The Commonwealth Armies and the Korean War: An Alliance Study. Manchester University Press, 1990.