Why Are There Two Koreas?

After World War II, Korea and Vietnam were liberated from Japanese occupation. Leaders could not agree on how to organize their government, so they split!

Jan 30, 2023By Owen Rust, MA Economics in progress w/ MPA

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The end of World War II brought about independence for many Asian countries that had long been colonies of the Empire of Japan. However, there were often strong disagreements about what type of government and society these newly-independent nations should have. Communism had become popular since the 1920s, and many pro-communist leaders in nations freed from Japanese rule wanted to form states based on guidance from the Soviet Union. Other leaders rejected communism as authoritarian and in violation of cultural and religious traditions, preferring to model states after Western nations. To avoid civil war, both Korea and Vietnam split in half, with pro-communists organizing a government in the North and anti-communists organizing a government in the South.


Setting the Stage: Karl Marx & the Communist Manifesto

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A book cover of The Communist Manifesto (1848), written by Karl Marx and Friedrich Engels, which launched the philosophy of communism, via the World Socialist Web Site (WSWS)


In the mid-1800s, life was often difficult for workers. Conditions were often harsh, the pay was low, and few laws or organizations existed to help those in poverty. Political philosopher Karl Marx wrote a powerful essay on the class struggle between the workers (proletariat) and the capitalist class (bourgeoisie). He advocated for a system of public ownership of all capital to prevent the exploitation of labor. This would mean the elimination of most private property rights, as factories were owned by wealthy private citizens. Although Marx’s philosophies became popular with many workers, they were strongly resisted by the wealthy.


Marx predicted that communism would come to replace free market capitalism in developed nations, such as across Europe and the United States. These nations were industrialized and had large populations of downtrodden factory workers. He argued that long-term profits enjoyed by capitalists were only possible through the exploitation of labor. Although highly controversial, Marx’s theories have been considered some of the most influential of the modern era.


Setting the Stage: The Communist Revolution (1917)

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An image of V.I. Lenin, leader of the Communist Revolution, in front of the red flag of the Soviet Union, via the Foundation for Economic Education


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Unfortunately for Marx, the wave of revolutions did not occur in his lifetime. In 1917, however, the chaos of World War I provided an opportunity for communist reformers in Russia. Plagued with economic problems and weak national leadership, Russia was performing poorly in the War. Germany sent a Russian exile, Vladimir Lenin, back to Russia in 1917 to encourage revolution. The Communist Revolution, also known as the Russian or Bolshevik Revolution, erupted in the autumn of 1917 and quickly overthrew the temporary government that had replaced Tsar Nicholas II.


The resulting Russian Civil War, fought between pro-communist Reds and anti-communist Whites, was eventually won definitively by the Reds in 1922. The Reds founded a new nation, the Union of Soviet Socialist Republics (USSR), commonly known as the Soviet Union, on December 30, 1922. It consisted of Russia and several bordering states. Until the end of World War II, the Soviet Union actively supported the international expansion of communism through its Comintern.


1922-45: Soviet Support for Pro-Communist Leaders

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A photograph of the first North Korean dictator Kim Il-sung, who lived in the Soviet Union during World War II, via PBS


Communist reformers, revolutionaries, and supporters were persecuted before and during World War II by both Nazi Germany and imperial Japan. The Soviet Union supported pro-communist revolutionaries, such as during the Spanish Civil War (1936-39), as well as opponents of its enemies, which included Japan. Hostilities between the Soviet Union and Japan went back to 1904 when the Russo-Japanese War began. As a result, the USSR was supportive of revolutionaries in China who were fighting the Japanese in the late 1930s. One of these revolutionaries happened to be a Korean man named Kim Il-sung, whose military unit defected to the Soviets in 1940 from northern China.


Kim Il-sung received military and political training from the Soviet Union and went on to fight the Japanese during World War II. As the Soviets began liberating territory from the Axis Powers, Germany and Japan, it was able to install hand-picked communist leaders to set up pro-Soviet governments. While this mostly occurred in eastern Europe, it also occurred suddenly in east Asia as the Soviet Union entered the war against Japan at the last minute. By the time of Japan’s formal surrender, the Soviets had occupied northeastern China and northern Korea.


1947-1950: Korean Peninsula Divided at 38th Parallel

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A map of North and South Korea separated at the 38th parallel, via the Royal British Legion


At the end of World War II, the Japanese on the Korean peninsula – which Japan had held as a colony since 1910 – surrendered to the United States in the south and the Soviet Union in the north. On September 9, 1945, the 38th parallel was announced as the dividing line between the American occupation zone and the Soviet occupation zone, with Japanese troops ordered to surrender to whichever power was on their side of the parallel. In November 1947, the United Nations created a task force to hold free elections across Korea to establish a new national government. However, the Soviet Union denied this task force to operate in its zone north of the 38th parallel, thus formalizing a division between free South Korea and communist North Korea.


Between May and August of 1948, the Republic of Korea (ROK, or South Korea) government was established, and the United States recognized the new nation on January 1, 1949. At the same time, a government was also set up in North Korea, with Kim Il-sung taking the position of premier of the Democratic People’s Republic of Korea (DPRK, or North Korea) on September 10, 1948. In December 1948, the United Nations recognized South Korea’s government but not that of North Korea. Between December 1948 and June 1949, both Soviet and American military forces left their respective Koreas, leaving the two new nations as sovereign states.


1950-1953: The Korean War

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An image of UN/US Korean War commander Douglas MacArthur superimposed over a map of a divided Korea, via the Imperial War Museums (IWM)


Although South Korea had been established as a democratic state, it suffered civil unrest in 1948. North Korea, which wished to reunify the peninsula under a single government, likely saw the unrest as a sign of weakness and an opportunity to exploit. In the autumn of 1949, the communists won the Chinese Civil War, turning China into Red China. Now backed by two communist powers, both economically and physically, North Korea was in a position to attempt to seize control of the Korean Peninsula by force. On June 25, 1950, its army stormed across the 38th parallel and into South Korea.


The United Nations sought help to protect South Korea, and the United States responded quickly. The US military led the UN military response, and a score of other countries contributed as well. Between June 1950 and April 1951, the rival armies pushed each other back and forth: Despite almost pushing South Korean forces into the sea by September 1950, the North Koreans were surprised and pushed north by a US amphibious landing at Inchon. After almost being pushed out of the war themselves by November, the North Koreans were saved by a sudden influx of Chinese troops, who drove the US back south. Intense fighting continued, and US commander Douglas MacArthur was controversially removed from his command in April 1951 for aggressively pursuing the war despite US president Harry S. Truman’s hopes to negotiate for peace.


1953: Creation of the Demilitarized Zone (DMZ)

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Representatives from the United States (left) and North Korea (right) sign the cease-fire ending the Korean War on July 23,1953, via the National Museum of the United States Air Force


After the relief of MacArthur in April 1951, the war began to bog down into a stalemate. President Truman wanted to avoid continued high casualties, as did leaders of China. Although North Korea and South Korea appeared willing to fight to the brutal finish, the three large powers backing the different Koreas no longer wished to do so. Talks of a truce began in July 1951. Over the next two years, fighting largely evolved into defensive fortifications, mostly near the pre-war border of the 38th parallel. Eventually, the communists suggested that the two nations return to their pre-war borders, though the UN refused on the grounds that the border was difficult to defend.


Ultimately, the war ended with a new border that was roughly similar to the 38th parallel. A demilitarized zone created in July 1953 replaced the horizontal line of the parallel with a more meandering path. It actually cost North Korea some 1,500 miles in territory but left South Korea’s capital city of Seoul within striking distance of the border. A cease-fire was signed on July 23, 1953, but no peace treaty formally ended the war. The demilitarized zone, known as the DMZ, remains one of the most heavily guarded places on earth. It is two and a half miles wide and 150 miles long, featuring the best soldiers and equipment of both North Korea and South Korea in a show of force.


1953-1991: North Korea Navigates Communist Allies

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A photograph of US Navy sailors being taken into captivity in North Korea following the capture of the USS Pueblo in 1968, via National Public Radio (NPR)


Throughout the Cold War, North Korea remained tightly allied with the Soviet Union and other communist countries. During the Vietnam War, it sent fighter pilots to assist communist North Vietnam. North Korea’s shared border with China forced it to strategically negotiate its support for the Soviet Union and China during the Sino-Soviet split of the early 1960s. As China increasingly distanced itself from the Soviet Union in the 1960s, North Korea shifted its firm support for the Soviet Union to be warmer to China. Over time, it came to formally adopt the philosophy of Juche, or self-sufficiency, in order to be less economically dependent on the two communist powers, from whom it received both economic and military aid.


In 1968, North Korea tested the patience of its allies by capturing the USS Pueblo in international waters and holding its crew hostage for 11 months. The Soviet Union did not appreciate the provocation during an era of relaxed tensions known as detente, and urged North Korea to release the ship’s crew. North Vietnam, a Soviet ally, also did not appreciate the incident because it likely amplified US activities during the ongoing Vietnam War. As a result of the Pueblo incident, North Korea eventually grew closer to China, which had offered its public support, though it remained ideologically closer to the Soviet Union. The end of the Cold War in 1991 ended generous economic support for North Korea, resulting in turmoil.


1990s-2000s: Inter-Korean Economic Ties & Exploration of Reunification

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A map showing special economic zones in North Korea, featuring cooperation between North and South Korea, via ResearchGate


The end of the Cold War was disastrous for North Korea’s economy, as it meant the end of economic aid. Unlike China and the Soviet Union, which had begun economic reforms in 1979 and 1985, respectively, North Korea had ardently remained a centrally planned command economy. Needing to develop its economy, North Korea began reaching out to South Korea for economic cooperation during the waning days of the Cold War. Special Economic Zones were established beginning in 1991, bringing South Korean industrial investment to the North.


After the Cold War, the reunification of Germany piqued public interest in the potential reunification of Korea. In 2000, the first Inter-Korean Summit was held in June in North Korea’s capital city, Pyongyang. Although there was little concrete reform, both Koreas agreed to the concept of reunification “in an independent way,” meaning not through warfare. Unfortunately, expansion of economic cooperation remained limited during the 2000s, with incidents sometimes reversing progress, such as the shooting of a South Korean tourist by a North Korean soldier in 2008 suspending tourism.


1990s-2010s: Economic Woes & Nuclear Fears Complicate Reunification

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A photograph of farmers in North Korea, via International Crisis Group


Unfortunately, the economic turmoil of the 1990s complicated the path toward reunification of Korea. North Korea needed economic aid and routinely attempted to secure it by dangling its nuclear program as a bargaining chip. Beginning in 1994, North Korea would offer to reduce its plutonium enrichment in exchange for aid. It also went to great lengths to project strength and hide problems, such as the horrific famine believed to have occurred between 1994 and 1998. This meant that North Korea refused to ask South Korea or the West for certain exports, lest it expose that North Korea was not enjoying socialist prosperity.


On October 9, 2006, North Korea tested its first nuclear weapon. This increased tensions on the peninsula, with the possibility that North Korea will use “nuclear blackmail” to win economic aid from South Korea, Japan, and the West rather than negotiate in good faith. Under dictator Kim Jong-il, son of dictator Kim Il-sung, North Korea continued to develop its nuclear capabilities through 2011, when the former passed away. Kim Jong-un took power in 2012 and quickly revealed himself to be a hard-liner like his father and grandfather, further eroding chances that the peninsula would be reunited peacefully.


2010s-2020s: Continued Provocations

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A graphic showing the range of North Korea’s ballistic missiles, via the Center for Strategic & International Studies (CSIS)


Since its first nuclear weapon was detonated in 2006, North Korea has steadily pursued a nuclear arsenal, especially delivery systems like long-range ballistic missiles. While North Korea’s economy remains sluggish and outdated, and its conventional military is relegated to using Soviet-era weaponry, its ballistic missile capabilities have improved. It is believed that North Korea spends much of its GDP on its military and a substantial percentage of the military funding on its nuclear program. Although North Korea’s armor and air power are obsolete, its 1.3 million-strong army and thousands of heavy artillery pieces are a painful threat to South Korea’s capital, Seoul. Combined with nuclear, chemical, and biological weapons, North Korea’s giant army remains a deadly threat to South Korea.


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North Korea display


Over the past decade, North Korea has steadily expanded the range of its ballistic missiles, perhaps even threatening the continental United States with a nuclear strike. It is feared that North Korea may, in the event of a regime-ending crisis, threaten nuclear war to secure enough economic and industrial aid to regain control. Sadly, this makes any political overtures of peaceful reunification of Korea unlikely for the foreseeable future.

Author Image

By Owen RustMA Economics in progress w/ MPAOwen is a high school teacher and college adjunct in West Texas. He has an MPA degree from the University of Wyoming and is close to completing a Master’s in Finance and Economics from West Texas A&M. He has taught World History, U.S. History, and freshman and sophomore English at the high school level, and Economics, Government, and Sociology at the college level as a dual-credit instructor and adjunct. His interests include Government and Politics, Economics, and Sociology.