Korean War in 1950 (UNSC)

Educator Overview

Case Overview

Set in September 1950. At the conclusion of World War II, Korea—formerly under Japanese control—was divided at the thirty-eighth parallel into a U.S.-occupied south and a Soviet-occupied north. Although the division was meant to be temporary, by 1948 both countries had declared independence. North Korea became a Soviet-supported communist state; South Korea was supported by the United States. Two years later, North Korea invaded South Korea in an attempt to bring the entire peninsula under its control. After several weeks of fighting, UN and South Korean forces were defending an area called the Pusan perimeter, in the southernmost portion of the peninsula. General Douglas MacArthur, who was commanding U.S. and allied forces as part of a UN mission, was also making plans for a landing at Inchon, near the South Korean capital of Seoul, in order to surprise North Korean troops and recapture Seoul.  

Anticipating the possible success of the Inchon landing, The UN secretary-general has convened the Security Council to discuss the situation in Korea, specifically whether to extend the UN military intervention north of the thirty-eighth parallel in an attempt to unify the Korean Peninsula. Security Council members will have to weigh the risks of such an intervention, and whether intervention offers a better opportunity to form a durable peace than stopping at the thirty-eighth parallel would.

Decision Point

The UN secretary-general has convened the Security Council to discuss the situation in Korea, specifically whether to extend the UN military intervention north of the thirty-eighth parallel in an attempt to unify the Korean Peninsula. The secretary-general has made clear that this decision depends on the success of the Inchon landing and victory in South Korea. Security Council members will need to consider a few critical questions. First, what is at stake in the conflict? Is it just a Korean national issue fueled by north-south rivalry, each side seeking to lead a unified nation, or could the conflict become a major flash point in the Cold War? Second, what are the chances of Soviet or Chinese intervention if UN forces invade North Korea? Finally, does reunifying Korea offer a better prospect of a durable peace than stopping at the thirty-eighth parallel would? 

Learning Goals

CFR Education simulations use a variety of pedagogical tools to create an effective, meaningful, and memorable learning experience for students that builds their global literacy. Students will develop crucial skills such as critical thinking, communication, collaboration, and creativity. Students will complete authentic assessments that feel relevant: instead of five-paragraph essays and book reports, students will write policy memos and participate in a role-play of a meeting of a foreign policy–making body. There are no right or wrong answers in actual policy deliberations, and there are none here, either; students will walk away from this experience with an appreciation for the complexity of policy questions.

In this simulation, students will learn about the UN Security Council, as well as meeting these learning outcomes specific to this simulation:

  • Students will understand the factors that led to the Korean War and what led to the UN Security Council approving military intervention.
  • Students will consider key disagreements within the UN Security Council, particularly regarding the role of the United States and the appropriate response to the war.
  • Students will evaluate the options available to the UN Security Council related to intervention above the thirty-eighth parallel.

Concepts and Issues



  • U.S. support for democratic governance
  • Costs, benefits, and risks of military interventions
  • U.S. interests in East Asia
  • The UN Security Council and the U.S. role at the United Nations
  • Early flash points in the Cold War
  • Security and diplomacy in Northeast Asia
  • Chinese and Soviet support of North Korea

Policy Options: Educator's Guide

Little consensus could be found in the UN Security Council by late summer 1950. Until that point nearly every resolution on the issue had passed unanimously. However,  the Soviet representative’s return to the council in August 1950 and his assumption of the council presidency in the same month brought the council into a new stage of conflict. 

On the one hand were those—above all the United States—who saw intervention above the thirty-eighth parallel to be necessary and imperative to repel Communist aggression. Members of this camp, including the United Kingdom and the Republic of China, interpreted Resolution 83 as an authorization of any and all action that would unify the two countries and reestablish peace on the peninsula. These nations called for a UN resolution authorizing an intervention above the thirty-eighth parallel with the goal of defeating North Korea and holding UN-supervised elections on the peninsula. This view pleased MacArthur. In mid-July, just weeks after the war began, MacArthur told other military leaders, “I intend to destroy and not to drive back the North Korean forces. I may need to occupy all of North Korea.” If this was not possible, the United States and its allies advocated for a resolution that condemned North Korea for continued defiance of the United Nations and called on all states to refrain from assisting the invaders. 

The Soviet Union and its allies were starkly opposed to UN intervention of any nature, let alone above the thirty-eighth parallel. The Soviet representative called the intervention illegitimate, asserting that the Korean War was a civil war and that the United Nations had no right to intervene. More importantly, he maintained that the UN Security Council was becoming a U.S. puppet, arguing that “the United Nations was allowing itself to become the tool of reactionary American ruling classes to suppress national liberation movements in Asia.” Accordingly, the Soviet Union called for an immediate cease-fire and withdrawal of foreign troops. It proposed that once peace was established, Korea should hold a joint north-south election for a national assembly and establish an interim government under observation from a UN committee. 

Between these two poles were countries that called for a peaceful resolution of the conflict. Many had supported the United States initially, but were now wary that the powerful permanent member was wielding too much influence in “shaping the agenda” at the United Nations and would drag the United Nations into a third world war. Others, including France, faced domestic political opposition to the war or were embroiled in their own conflicts abroad. India, a nonpermanent member at the time of the invasion, argued that “every attempt should be made at peaceful settlement before United Nations troops crossed the Parallel.” These governments were staunchly opposed to military operations in North Korea. This was primarily because of the risk of drawing the Soviet Union or Communist China into the conflict. They proposed a variety of policies focused on mediation and negotiation, including cease-fires, the creation of a neutral buffer zone at the thirty-eighth parallel, and multilateral peace talks. 

During this time, much of the disagreement at the council revolved around the role of the United States in the conflict. By the fall of 1950, many UN member states had expressed displeasure at the United States’ apparent monopolization of the UN Command in South Korea. Many of the United States’ allies were extremely cautious of involving Communist China, and repeatedly warned U.S. representatives that “the United Nations was concerned only with the question of Korea, and that it should not under any circumstances become embroiled in the quarrel of the two Chinas.” Security Council members also wanted to emphasize the collective nature of UN action, reportedly requesting changes to resolutions to reduce the number of references to the United States. 

At the time of North Korea’s attack on South Korea, nearly every member of the Security Council shared the view that the invasion was a breach of international peace and security. Many member states had supported Resolutions 82 and 83 with a view to reestablishing the prewar status quo. These member states saw any conflict on the peninsula as incompatible with UN policy toward Korea. As the liberation of South Korea neared, however, members were split on what steps to take next. One thing was certain: any decision made by the Security Council would be enormously consequential for the course of the war.