Tiếng Việt
The Korean War erupted on June 25, 1950, when around 75,000 troops from the North Korean People’s Army crossed the 38th Parallel—the dividing line between the Soviet-backed Democratic People’s Republic of Korea in the North and the Western-aligned Republic of Korea in the South. This invasion marked the first military action of the Cold War.
By July 1950, U.S. forces had entered the conflict to support South Korea. For American officials, this was not merely a regional war but a battle against international communism. After phases of back-and-forth fighting along the 38th Parallel, the war reached a stalemate, with mounting casualties yielding no clear resolution.
Meanwhile, U.S. officials worked to negotiate a ceasefire with North Korea, fearing that a prolonged conflict could escalate into a full-scale war with Russia and China—or, as some warned, even World War III.
Ultimately, the Korean War ended in July 1953. However, it came at a staggering cost: approximately 5 million soldiers and civilians lost their lives. In the United States, it is often referred to as “The Forgotten War” due to receiving less attention than World War I, World War II, or the Vietnam War.
To this day, the Korean Peninsula remains divided.
North Korea vs. South Korea
“If the best minds in the world had set out to find the worst possible location to fight this damned war,” U.S. Secretary of State Dean Acheson (1893-1971) once remarked, “the unanimous choice would have been Korea.” The Korean Peninsula became a flashpoint for the U.S. almost by accident.
Since the early 20th century, Korea had been part of the Japanese Empire. After World War II, the fate of Japan’s imperial territories was determined by the U.S. and the Soviet Union. In August 1945, two young aides at the U.S. State Department divided the Korean Peninsula into two zones along the 38th Parallel. The North was occupied by the Soviet Union, while the South came under U.S. administration.
Did You Know?
Unlike World War II and the Vietnam War, the Korean War received relatively little attention from the American media. Its most prominent depiction in popular culture is the iconic television series MASH*, set in a field hospital in South Korea. Airing from 1972 to 1983, the show’s finale remains the most-watched episode in U.S. television history.
By the late 1940s, two new states had emerged on the Korean Peninsula. In the South, the anti-communist dictator Syngman Rhee (1875-1965) received reluctant support from the U.S. government; in the North, the communist leader Kim Il-sung (1912-1994) enjoyed more enthusiastic backing from the Soviet Union.
However, both leaders were dissatisfied with controlling only half the peninsula, and border clashes were frequent. Before the war officially began, nearly 10,000 soldiers from both North and South had died in smaller skirmishes.
The Korean War and the Cold War
Nevertheless, North Korea’s 1950 invasion caught U.S. officials by surprise. To them, this was not just a border conflict between two unstable dictatorships on the other side of the globe but the first step in a communist campaign to dominate the world. For this reason, many senior policymakers saw staying out of the conflict as unthinkable.
(In fact, in April 1950, a National Security Council report known as NSC-68 recommended that the U.S. use military force to “contain” communist expansion wherever it emerged, “regardless of the strategic or economic value of the lands in question.”)
President Harry Truman (1884-1972) declared, “If we let Korea fall, the Soviet Union will keep right on going and swallow up one piece after another.” The war on the Korean Peninsula became a symbol of the global struggle between East and West, good and evil, in the context of the Cold War.
As North Korean forces advanced deep into Seoul—South Korea’s capital—the United States prepared to deploy troops, entering a war not only against North Korea but against communism worldwide.
Initially, the war’s objective was defensive: to repel communist forces from South Korea. However, the campaign did not go smoothly for the Allies. North Korea’s army was well-organized, trained, and equipped. In contrast, President Rhee’s South Korean forces were panicked, fearful, and prone to fleeing the battlefield at the slightest threat.
Adding to the challenges, that summer was one of the hottest and driest on record. Thirsty American soldiers were forced to drink water from rice paddies fertilized with human waste, leading to widespread intestinal diseases and other illnesses.
By late summer, President Harry Truman and General Douglas MacArthur (1880-1964), the commander of U.S. forces in Asia, decided to shift the war’s objective. For the Allies, the Korean War now became an offensive campaign aimed at “liberating” the North from communism.
The new strategy initially yielded significant success. The Incheon Landing, an amphibious assault on the city of Incheon, drove North Korean forces out of Seoul and back across the 38th Parallel. However, as U.S. troops crossed this boundary and advanced toward the Yalu River—the border between North Korea and communist China—China grew alarmed about protecting its territory.
“There Is No Substitute for Victory”
This was precisely what President Truman and his advisors desperately wanted to avoid: they believed a full-scale war would trigger Soviet aggression in Europe, the deployment of nuclear weapons, and the senseless deaths of millions. However, for General Douglas MacArthur, anything short of escalating the conflict was “appeasement”—an unacceptable concession to communism.
While Truman sought to prevent war with China, MacArthur did everything possible to provoke it. Finally, in March 1951, he sent a letter to Joseph Martin, a Republican House leader who supported all-out war with China and was known to leak such correspondence to the press. In the letter, MacArthur wrote, “There is no substitute for victory” over international communism.
For President Truman, this letter was the final straw. On April 11, 1951, he relieved General MacArthur of his command for insubordination.
Chinese leader Mao Zedong (1893-1976) deployed troops to North Korea and warned the U.S. not to approach the Yalu River border, lest it face all-out war.
The Korean War Reaches a Stalemate
In July 1951, President Harry Truman and his new military commanders began peace talks at Panmunjom. However, fighting continued along the 38th Parallel as negotiations stalled. Both sides were willing to accept a ceasefire maintaining the boundary at the 38th Parallel, but they could not agree on whether prisoners of war should be forcibly “repatriated.” (China and North Korea agreed, while the U.S. opposed.)
Finally, after more than two years of tense negotiations, the warring parties signed an armistice on July 27, 1953. The agreement allowed prisoners of war to choose where they wished to remain, established a new boundary near the 38th Parallel that gave South Korea an additional 1,500 square miles of territory, and created a 2-mile-wide “demilitarized zone” that still exists today.
Casualties of the Korean War
Though relatively short-lived, the Korean War was one of the bloodiest conflicts in history. Nearly 5 million people perished, with more than half—about 10% of Korea’s pre-war population—being civilians. (This civilian casualty rate exceeds that of World War II and the Vietnam War.)
Nearly 40,000 American soldiers died in combat in Korea, and over 100,000 were wounded. Today, these soldiers are commemorated at the Korean War Veterans Memorial near the Lincoln Memorial on the National Mall in Washington, D.C., featuring 19 steel statues of servicemen. Additionally, in Fullerton, California, the Korean War Memorial—the first of its kind on the U.S. West Coast—honors over 30,000 American soldiers who died in the conflict.
Conclusion
Through this article, Pywar hopes to provide a comprehensive overview of the Korean War—a defining event of the 20th century. From its causes and tense developments along the 38th Parallel to its toll of millions of casualties, the war left not only devastation but also a profound impact on Cold War international relations. Though it ended in 1953, its legacy endures through the demilitarized zone and memorials.
