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The Korean War

Learn about the first hot war in the Cold War: Korea. 

Overview

  • In June 1950 communist North Korea invaded South Korea. The United States came to the aid of South Korea at the head of a United Nations force composed of more than a dozen countries.
  • Communist China joined North Korea in the war in November 1950, unleashing a massive Chinese ground attack against American forces. The Soviet Union also covertly supported North Korea.
  • After three years of fighting, the war ended in a stalemate with the border between North and South Korea near where it had been at the war’s beginning.
  • This was the first hot war of the Cold War, and in it the United States demonstrated its continued commitment to containment (the idea that the US would ultimately defeat communism by containing its spread).

The Korean War begins

When Korea was liberated from Japanese control at the end of the Second World War, the United States and the Soviet Union agreed temporarily to divide Korea at the 38th parallel of latitude north of the equator. This division resulted in the formation of two countries: communist North Korea (supported by the Soviets) and South Korea (supported by the United States).
Map of North Korea and South Korea. The red line indicates the present-day border between the two nations. Map adapted from Wikimedia Commons.
Five years after the country’s partition, the communist leader of North Korea, Kim Il Sung, decided to attempt to reunify Korea under his control. On June 25, 1950, Kim launched a surprise invasion of South Korea.1
Believing that the Soviet Union had backed the invasion, United States President Harry Truman and his advisers followed through on their policy of containment, refusing to allow communism to spread anywhere in the world. Within two days of the invasion, the United States had rallied the United Nations Security Council to declare support for South Korea. An American-led UN coalition deployed to South Korea.2
By August, North Korean forces had swept across almost all of South Korea; American forces held only a small defensive perimeter in the country’s southeast, near Busan. In September, however, under the command of General Douglas MacArthur, the United States launched a bold counter-offensive that included a daring amphibious landing in territory held by North Korean forces at Inchon, on South Korea’s western coast. Soon, US forces drove the North Koreans back to the border at the 38th parallel.

Beyond the 38th parallel

The Truman administration then made the decision to proceed across the 38th parallel into North Korea. But in late November 1950, as American forces neared the Chinese border, leaders in communist China (fearful that the United States might invade) sent tens of thousands of Chinese soldiers streaming into North Korea and drove the American and UN forces southward, back across the 38th parallel.3
Child refugees during the Korean War. Image courtesy Wikimedia Commons.
By spring 1951 the Americans had pushed to the 38th parallel once again. That same spring President Truman fired General MacArthur when MacArthur publicly challenged the administration’s strategy. The next two years saw periods of fierce fighting, but the border held. In 1953, an armistice established a status quo antebellum border near the border that had originally divided North and South Korea.
The heavily armed two-and-a-half mile wide DMZ (Demilitarized Zone) separating North and South Korea exists to this day.
About 36,500 American soldiers died in the war, as well as hundreds of thousands of soldiers and civilians from North Korea, South Korea, and coalition forces.

Korea in the context of the Cold War

In Korea, the United States demonstrated its continuing commitment to key elements of its Cold War strategy. It demonstrated its global leadership by committing its resources and soldiers in the fight against the spread of communism. The United States also confirmed its commitment to a foreign policy based on collective security by mobilizing other countries to support its position both politically and militarily.4
In Korea, the United States demonstrated the ideals expressed in the Truman Doctrine, which promised support for the "free peoples of the world" who wished to keep communist aggression at bay. Although the war ended where it began, the United States and its allies did succeed in preventing communism from overtaking South Korea.

What do you think?

Was the United States wise to fight in Korea? If Truman hadn’t contained communism in Korea what might the consequences have been?
Do you think the United States-led forces ought to have crossed into North Korea?
Who "won" the Korean War?

Want to join the conversation?

  • leaf orange style avatar for user Jeff Kelman
    Was the United States wise to fight in Korea? If Truman hadn’t contained communism in Korea what might the consequences have been?

    It is impossible for us to know with certainty what would have happened. Perhaps all of Korea would have gone communist, but then perhaps later they would have rebelled in unity and had a strong united free Korea today. There is no way to know with certainty, but I do not think it was appropriate for the United States to intervene. If people in South Korea wanted to leave, we should have offered them free access and the means to immigrate to the US, that is the extent of the US foreign policy that I would support. Non intervention and non violence is the only legitimate policy.

    Do you think the United States-led forces ought to have crossed into North Korea?

    I do not think that the United States forces ought to have been in North OR South Korea at all. Thus, this point is secondary to the first point of if the United States had any right to be in Korea, which I believe that they had no right to be in.

    Who "won" the Korean War?

    This is debatable. You could make quite fair arguments on behalf of both the North or the South, or the Russians, or the US for that matter. The fact that many lives were lost and the "border" returned only to the Status quo antebellum is proof to me that this war was another example of states sacrificing the lives of their citizens without reason.
    (23 votes)
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    • duskpin ultimate style avatar for user Harriet Buchanan
      I think it was wise to intervene, but only as part of a UN force...even if most of the force was U.S. We get into trouble when we attack unilaterally.

      Our stated objective when we went in was to drive North Korea back to the 38th parallel. If we had stopped there, we would probably have had the support of China in the north, but instead we pushed on to the Yalu River, and China reacted defensively. Even today China is a major constraint on North Korea going too far. We should appreciate and respect that.
      (20 votes)
  • piceratops ultimate style avatar for user Afiq Azraei
    For question number 2, the US-led forces made a mistake by approaching the Chinese border too fast. They should have already be carrying out negotiations by then.

    Or am I wrong?
    (13 votes)
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  • blobby green style avatar for user champagnevivsgomez237
    To what extent was the Korean War both a victory for the communists as well as democratic nations of the world
    (5 votes)
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    • primosaur ultimate style avatar for user Brian Pak
      I guess you could say that it was a victory for the communists since they showed the world that they could fight if a war were to start. It was also a victory for the democratic nations of the world, since they showed the world that they could protect other free nations across the ocean from falling to communism. Hope this helped!
      (5 votes)
  • blobby green style avatar for user Layne T
    ok so QU? if my mom had me at 14 then here mom had her at 14 then here moms mom had her at 14 then here moms moms mom had her at 14 then here moms moms moms mom had her at 14 then here moms mom mom mom mom had her at 14 then here moms mom mom mom mom mom mom had her at 14 will the all be still alive?
    (1 vote)
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    • aqualine tree style avatar for user David Alexander
      Let's start with you, and assume that you are 10. So, your Mom, who got pregnant at 13, is now 24. Her mom, who also got pregnant at 13, is now 38. HER mom, who also got pregnant at 13, is now 52, and her mom, who (incredible, isn't it) also got pregnant at 13 is 66. The next 14 year old mom is 80. Average life expectancy for women born in Korea in the 1950s was about 50 years old, so the ancestor who would now be 80 probably isn't living any more. Any of those ancestors born after 1960 might still be alive.

      I'd sumise, though, that a string of young pregnant girls that long (pregnant at 13, giving birth at 14) is kind of a family tragedy.
      (11 votes)
  • duskpin ultimate style avatar for user Albus Severus Potter - The Cursed Child?
    Who "won" the Korean War?
    Well this is a battle where there are no winners.This is a lose/lose situation. Innocent citizens lives were lost, thousands of firearms shot, and for what? The UN neither prevented or stalled the complete communist assimilation into North Korea. The UN forces became arrogant and pressed on too quickly and to far and what did that result in? More lives lost, this time from China too. And when the US in particular went too far too quickly, they lost the chance of winning the war. And we are right back where we started, but with more casualties and destruction. War is not a battle between arms. War is not a face-off between good and evil. It is a fight for views, and a regulation of will. Not a restriction of will, but the regulation of it. So, really, everyone lost.
    (5 votes)
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  • blobby green style avatar for user Roger Meraz
    Even though Synyman Rhee was not a "good" person, why does the US support him
    (3 votes)
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    • male robot hal style avatar for user RN
      The same reason the US accuses the USSR of the Gulags, but had institutional racial segregation and a support for slavery not too long ago. It was a political advantage to support a anti-Communist government as a buffer to stop the spread of Communism to the rest of Asia. This was known as the "Domino Theory", where if Communism were to be implemented in one nation- neighboring states would fall to the influence of Communism as well. Therefore the US as a policy of containment supported the South Korean government.
      (5 votes)
  • piceratops ultimate style avatar for user Eli Canham
    1. Yes, if Truman didn't support South Korean forces then North Korea would've been able to force South Korean men to aid them and probably would've taken Japan.

    2. Maybe they shouldn't have because of the losses they should've thought about.

    3. Nobody won the Korean war. An armistice doesn't mean an official end to a war all it means is that they will pull back and stop fighting, in other words they are still in a state of war with no bullets flying.
    (2 votes)
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    • piceratops ultimate style avatar for user Jet Simon
      1. Incorrect. If North Korea united the peninsula there would be no way that they would takeover Japan, think about it. The US had most of its Pacific forces there who were freshly battled hardened soldiers and they would be threatened with a nuke anyways.
      2. Basically what I said in point number 1
      3. True, there was no peace treaty that was accepted by both sides and the two Koreas remain technically at war to this day.
      (7 votes)
  • leafers ultimate style avatar for user Chaba Rogelio
    Why does the article say "The Truman administration then made the decision to proceed across the 38th parallel into North Korea."? This suggests that Truman or his representatives were at fault. In every other account I've read, Truman only wanted the North Koreans pushed back to the 38th parallel; it was General MacArthur who went against orders and tried to push them all the way back to China (hence why Truman fired him). Which way is it, or is there some debate?
    (5 votes)
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    • aqualine ultimate style avatar for user Ben McCuskey
      Pressed by MacArthur, Truman authorized him to pursue the North Korean troops north of the 38th parallel. The United States succeeded in getting a new U.N. resolution. It called for the destruction of the North Korean Army and the reunification of Korea under a democratic government.

      American troops led the offensive beyond the 38th parallel, pushing the North Koreans toward the Yalu River, which separated Korea from Communist China. Despite assurances by the United States that U.N. troops would stop at the Yalu, the Chinese government warned that any foreign forces north of the 38th parallel posed a threat to China's security.


      https://www.crf-usa.org/bill-of-rights-in-action/bria-17-3-b-truman-macarthur-and-the-korean-war.html#:~:text=Pressed%20by%20MacArthur%2C%20Truman%20authorized,in%20getting%20a%20new%20U.N.&text=American%20troops%20led%20the%20offensive,separated%20Korea%20from%20Communist%20China.
      (1 vote)
  • leaf grey style avatar for user Grant Race-car
    wat if koran one the war
    (0 votes)
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  • blobby green style avatar for user Mackenzie Robbins
    Was the United States wise to fight in Korea? If Truman hadn’t contained communism in Korea what might the consequences have been?

    The U.S was wise to fight in Korea because we upheld our promise in the Truman Doctrine to help free allies. If we had not helped communism would have spread further and our credibility as a country would have been lost.
    (4 votes)
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