The Korean War (1950-1953) was the first military action of the Cold War. It was triggered by the invasion of South Korea on June 25, 1950 by 75,000 members of the North Korean People’s Army. The line they crossed, the 38th parallel, was created in 1945 to separate the Soviet-backed Democratic People’s Republic of Korea (now North Korea) and the United States-backed Republic of Korea towards South. The Korean War was a civil conflict that turned into a proxy war between superpowers vying for communism and democracy. Between 2 and 4 million people have died, of which 70% are civilians. No peace treaty has ever been signed.
WATCH: The Korean War in HISTORY Vault
What caused the Korean War?
“The Korean War was a civil war,” says Charles Kim, associate professor at the Korean Foundation, Department of History, University of Wisconsin-Madison. Korea was a unified kingdom for centuries before it was annexed by Japan after its victory in the Russo-Japanese War. The Japanese ruled Korea with an iron fist from 1910 to 1945. They used assimilationist tactics like banning the Korean language and de-emphasis of Korean history in favor of Japanese culture to weaken their influence. colony.
When Japan surrendered to the Allies after atomic bombs were dropped on Hiroshima and Nagasaki during World War II, control of the Korean Peninsula passed from Japan to the Americans and the Soviet Union. The superpowers chose to divide Korea among themselves at the 38e parallel, which roughly divided the peninsula. “It didn’t match any political, cultural or field boundaries,” Kim says. The Soviets established a communist government in the north, and the United States helped establish a military government in the south.
The DMZ line in the demilitarized zone between South Korea and North Korea, 1990 (Kurita KAKU / Gamma-Rapho via Getty Images)
“Back then, Korean politics ran the gamut from far-left communism to right-wing nationalists, all vying for power,” Kim says. “There was a lot of disagreement between the Soviet and American occupying forces, and with the polarization of the Korean leadership, it was an unstable situation,” Kim says. “Each considered the other to be illegitimate. The two wanted to invade each other to unify Korea.
Skirmishes dispersed at the borders from 1948 to 1950 simmered tensions. In 1948, the United States called on the United Nations to sponsor a vote for Koreans to determine their future government. When the North refused to participate, the South formed its own government in Seoul under the aegis of anti-Communist Syngman Rhee. In retaliation, Kim Il Sung, a former Communist guerrilla, was appointed Prime Minister of the Democratic People’s Republic of Korea (DPRK).
Il Sung went to Moscow in 1949 and again in 1950 to seek Soviet support to invade South Korea. “He succeeded in convincing Joseph Stalin to pledge his support for the invasion of South Korea. He also got a verbal commitment from China, ”Kim said.
When North Korea invaded South Korea on June 25, 1950, “North Korea was banking on the United States. do not come back, ”Kim says. The North Korean forces were strong; they had the help of experienced veterans of the Chinese Civil War, which had just ended in August 1949. The North Koreans advanced rapidly south. The world watched to see what would happen next.
Why did the United States get involved in the Korean War?
“Initially, the United States did not want to get involved in any invasion. They didn’t want to get tangled up with North Korea, let alone China or the Soviet Union, ”Kim says. Key events on the world stage have caused the United States to change course.
On August 29, 1949, the Soviets detonated their first atomic bomb. Klaus Fuchs, a physicist who had helped the United States build their atomic bomb program, had disclosed the “Fat Man” atomic bomb plan to the Soviets. The revelation stoked Cold War paranoia. Then, on October 1, 1949, communist revolutionary Mao Zedong announced the creation of the People’s Republic of China following the defeat of Chinese nationalists backed by the United States and led by Chiang Kai-shek. “The loss of China” was a phrase used by Republican critics of the Truman administration, ”Kim says.
Thousands of Chinese soldiers have been sent to help the North Koreans. “Mao Zedong was adamant in helping his North Korean allies. He wanted to improve the prestige of China in the communist world by liberating the South Koreans from US imperialist rule, ”Kim said.
President Truman orders US forces in South Korea
WATCH: July 19, 1950: President Truman orders US forces to fight in Korean War
On December 16, 1950, US President Harry Truman declared a state of emergency, proclaiming that “communist imperialism” was a threat to democracy. The following April, Truman received a document entitled National Security Council document number 68 (NSC-68). Created by the Department of Defense, State Department, CIA and other agencies, it advised the president to develop the defense industry to counter what these agencies saw as the threat of world communism. The recommendations cemented Truman’s next move.
On June 25, 1950, President Truman ordered US forces to travel to South Korea to repel the invasion from the North. “The Democrats must have seemed tough on Communism,” Kim said. “Truman used Korea to send a message that the United States will contain communism and come to the aid of its allies.”
The United States has never officially declared war on North Korea. Instead, Truman called the addition of ground troops “police action.” The Inch’on landing of American General Douglas MacArthur on September 8, 1950 turned the tide of the war and allowed the forces of the South to push north beyond the 38e parallel.
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Impact of the Korean War
MacArthur’s efforts were not enough to secure victory. The Korean War Armistice, signed on July 27, 1953, drew a new border between North Korea and South Korea, granting South Korea additional territory and demilitarizing the area between the two nations. A formal peace treaty was never signed.
Over 2.5 million people died during the Korean War. Despite two POW exchanges, Operation Little Switch and Operation Big Switch, 7,800 Americans are still missing in action, while South Korea is still looking for more than 124,000 servicemen.
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“The lack of a definitive conclusion to the Korean War has kept it alive as a major influence on Asian affairs,” says Sheila Miyoshi Jager, professor of East Asian studies at Oberlin and author of Brothers at War: The Endless Conflict in Korea.
She argues that the Korean War directly influenced President Lyndon B. Johnson’s policy in Vietnam: “Here is a prosperous sovereign nation, divided by the Cold War, threatened by its communist neighbor backed by China and the Soviet Union. Korea was now seen as a war that had succeeded in stopping Chinese Communist expansion in Asia.
Sandwiched between World War II and the Vietnam War, the Korean War has been dubbed “the forgotten war”. But for Jager, it is not over: “The Korean War continues to influence events in East Asia,” she said. Tensions between the United States and North Korea continue.
