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The Korean War

The Korean War

 Table of Contents

War in The Korean War

A War in Three Parts

The first six months of the Korean War witnessed three stunningly successful surprise attacks. Each one nearly led to total victory—first for the North Koreans, then for the Americans, then for the Chinese.

The North Korean Advance

The first great surprise attack of the Korean War was the one that started it—North Korea's sudden full-scale invasion of the South on 25 June 1950. The poorly trained, poorly equipped, poorly organized forces of South Korea's unloved leader Syngman Rhee immediately collapsed under the North Korean onslaught. Kim Il Sung's North Korean Communist army, benefiting from superior training and weaponry provided by the Soviet Union, moved quickly southward through the countryside, expecting to be greeted as liberators by South Korea's rural peasantry. While those hopes largely proved unfounded, several crack units of the South Korean military did defect to the North. And those South Korean police and soldiers who remained loyal to Syngman Rhee devoted nearly as much time and energy to hunting down and murdering Rhee's domestic political opponents—perhaps as many as 100,000 of them, just during the summer of 1950—as they did to defending their country from the North Korean attackers. As a result, the South Korean capital of Seoul fell to Communist forces just four days after the invasion began. In less than a month, North Korean forces gained control of almost the entire country, with South Korean troops (and their American allies, just beginning to arrive in Korea) confined to a small area around Pusan, at the very southern tip of the Korean Peninsula.

But the Communists couldn't quite finish the job. In the first days of August, American and South Korean troops finally managed to establish a firm defensive line—the "Pusan Perimeter"—and halt the North Korean advance. With more and more well-trained, well-armed American soldiers pouring into the Pusan area from overseas, the prospects for North Korean victory began to fade. Throughout August, the Americans—now outnumbering their opponents in manpower, tanks, and artillery, and maintaining a total monopoly in air power—turned back a series of desperate North Korean attacks aimed at ending the war. At the same time, however, the Americans had no success in pushing forward directly into the North Korean lines.

The Inchon Landings

On 25 September, the Americans struck back with a spectacularly successful surprise attack of their own. General Douglas MacArthur—ignoring earlier declarations by figures as powerful as Joint Chiefs Chairman Omar Bradley that "large-scale amphibious operations will never happen again"—organized one of the largest and most successful amphibious attacks in American military history.

MacArthur deployed a huge task force of more than 300 ships carrying nearly 70,000 men to carry out a surprise attack on the port of Inchon, far to the north of the Pusan battle zone. If it could be captured, Inchon, located on the west coast of Korea near the original border between North and South, would offer easy access to the captured South Korean capital of Seoul. More important, a beachhead at Inchon would offer American forces a brilliant opportunity to cut off vital supply lines and routes of retreat for the bulk of the North Korean army, deployed far to the south at the Pusan Perimeter.

MacArthur's gambit to open up a huge new offensive hundreds of miles behind enemy lines caught the North Koreans totally by surprise. The massive invasion force quickly overwhelmed the light defenses left in place by the Communists at Inchon. Within days, American troops liberated Seoul and began wreaking havoc against North Korean forces strung out between Pusan and the 38th parallel. North Korean troops that had held the line for a month at the Pusan Perimeter fell quickly into disorganized retreat, fleeing for the relative safety of North Korean territory. But American and South Korean troops waited along all corridors of retreat, inflicting grave casualties in so-called "mop-up operations" against panicked and disorganized enemy forces. Fewer than half of the 70,000 Communist soldiers deployed to Pusan in August 1950 ever made it back to North Korea. In less than two weeks in the second half of September, the once-fearsome North Korean military virtually ceased to exist as an effective fighting force.

Advance and Reverse

The survival of South Korea now appeared to be all but guaranteed. The only question was whether American forces should push on, moving beyond the 38th parallel to try to liberate all of Korea from Communist control. With the North Korean army in tatters, it seemed that nothing stood in the Americans' way. MacArthur, hoping to cement his reputation as one of the great military geniuses in American history, had no reservations about pushing on to total victory. Truman, hoping to restore his reputation and resurrect his fading presidency by leading the United States to a great triumph over a Communist foe, was just as enthusiastic about taking the fight to the North. On September 27, Truman ordered MacArthur to advance into North Korea, proceeding as long as he did not encounter Soviet or Chinese opposition and he remained confident of victory.

As Truman's orders suggested, the only real danger was that an expansion of American war aims from the rescue of the South to the destruction of the North might cause either Russia or China—enemies vastly more powerful than Kim Il Sung—to intervene directly in the conflict. But neither Truman nor MacArthur thought such a prospect was likely. Soviet or Chinese intervention might have been decisive earlier in the conflict, the Americans reasoned, when it might have allowed Kim to complete his victory before the Americans could organize an effective defense. But if the Chinese and Soviets hadn't come in then, why would they do so now, when prospects looked so bleak and defeat looked so likely? Besides, with American aircraft in total control of the skies over the Chinese-Korean border, any incursion by Chinese forces across the Yalu River would face devastating bombing attacks. When Truman and MacArthur met on 15 October at Wake Island to coordinate strategy for the final phase of the war, the general confidently reported, "We are no longer fearful of [Chinese] intervention. We no longer stand hat in hand."19 There is no evidence that Truman disagreed. The meeting ended with both men confident that total victory in Korea would be achieved within weeks.

Chinese Intervention

What neither Truman nor MacArthur realized, however, was that China's invasion had already occurred; some 300,000 soldiers, trained in guerilla combat, had secretly crossed the border by foot under cover of darkness, then built carefully camouflaged positions in the rugged mountains of North Korea, all but invisible to American planes patrolling the skies above. There they lay in wait for the perfect moment to spring a devastating ambush on their overconfident and overextended American foes.

American troops in the field captured their first Chinese prisoner as early as 26 October, but MacArthur's high command did not realize that this was a sign of a much larger Chinese threat. The Americans continued pushing northward, moving all the way to the banks of the Yalu by late November.

On 24 November, MacArthur publicly announced a grand offensive that he promised would end the war by Christmas. The Chinese had other plans. Two days later, tens of thousands of Chinese soldiers surged across the Yalu and attacked the forward positions of the overstretched American forces. At the same time, the hundreds of thousands of Chinese troops already in North Korea emerged from their hiding places, launching devastatingly successful assaults against the flanks of the American and South Korean lines.

Now it was the Americans' turn to fall into panicked retreat. It took less than three weeks for the Chinese to drive MacArthur's army back south of the 38th parallel. In the process, in fighting conducted in bitter cold and brutal terrain, the Communists captured or killed thousands of American and South Korean troops. In one particularly desperate moment, almost 30,000 Americans nearly found themselves completely encircled by a Chinese force four times as large near the frozen Chosin Reservoir high in the mountains of North Korea. The Americans' narrow escape after days of intense fighting prevented what would have been one of the worst tactical catastrophes in American military history; MacArthur's high command was already considering the use of nuclear weapons against China if needed to prevent the total destruction of those 30,000 men at Chosin Reservoir. Such drastic action, which surely would have instigated World War III, ultimately and fortunately proved unnecessary. Still, deep disagreement between Truman and MacArthur over whether or not to risk starting a wider war in order to recover lost ground in Korea led to a bitter dispute between the two leaders that ended with Truman relieving MacArthur of his command. And all the while, the situation in Korea remained dire. By the end of 1950, Communist forces again controlled the North and looked poised to push on into the South.


Fortunately for the United States, the guerilla strategies that had served the Chinese so well in launching their surprise offensive now made it almost impossible for them to press their advantage. With no air force and little heavy machinery in Korea, the 300,000-man Chinese army depended—almost unbelievably—upon a supply line consisting of thousands of individual porters carrying vital food and equipment by foot or on bicycle. As the front line moved to the south, farther and farther from the Chinese border, sustaining and extending this manual-labor supply line proved more and more difficult. Early in 1951, just as the Americans were reorganizing an effective defensive line not far from the 38th parallel, China's offensive stalled out.

Throughout the first half of 1951, the two sides engaged in several months of inconclusive back-and-forth fighting. The Communists again captured, but then lost, the capital city of Seoul; American forces pushed north through Chinese lines, only to be driven back again. By the summer of 1951, the war settled into an uneasy stalemate, with both sides dug in to heavily entrenched positions along a line located, ironically, just miles from the 38th parallel that had divided North and South Korea since 1945. A conflict that had begun as a war of movement, with battle lines moving quickly from south to north to south again, now began to look more like the stagnant trench warfare of World War I. Both sides began shelling each other's lines, regularly unleashing barrages of artillery larger than any seen in either World War I or II. Casualties continued to mount, even though large-scale offensives had essentially ended.

With the war settling into a bloody and costly stalemate, with seemingly little hope remaining for victory for either side, pressure began to mount for the arrangement of a truce. The United Nations passed a resolution calling for a negotiated end to the Korean War as early as 1 February 1951. The Soviets publicly asked for a truce in July, and the first talks between American, Chinese, North Korean, and South Korean negotiators began a month later. But the peace negotiations did not go smoothly. Cease-fire talks dragged on and on for nearly two years, low-level fighting continuing to take place (and casualties continuing to rise) all the while. Half of the 36,000 American soldiers who lost their lives in Korea died after the peace talks began in August 1951.

As the costs of the Korean War, measured in both blood and treasure, continued to mount for seemingly no good purpose, Truman's standing with the American people plummeted to new depths. It would be a new president, Republican Dwight Eisenhower—elected in 1952 in part on the strength of his promise to end the war in Korea with dignity—who would finally oversee the signing of a cease-fire in July 1953. That agreement—signed by North Korea, China, and the United States, but not by South Korean leader Syngman Rhee—established a demilitarized zone (DMZ) along the entrenched front lines as the new border between North and South. The Korean DMZ runs slightly north of the 38th parallel in the eastern half of the country, slightly south of it in the west. All in all, three years of intense combat in Korea ended with the two sides facing off along a frontier that had barely moved from where it all began. The Korean War ended in a draw—a costly, frustrating, disillusioning draw.

War Not Over?

Or perhaps the Korean War didn't end at all. The agreement that ended active combat in July 1953 was technically only a cease-fire, not an official peace treaty. The United States Congress never rescinded the authorization for use of force in Korea it passed in 1950. Technically, a state of hostility continues to exist between the Korean War's combatants to this very day. And that hostility does not exist only on paper. Thousands of American soldiers are still deployed to the DMZ, joining their South Korean allies in keeping a perpetual watch over the North Korean troops stationed on the far side of the border, guarding against the possibility of any new Communist offensive in a 50-year-old war. Today, nearly two decades after the fall of the Soviet Union, the Cold War still lingers on along the barren strip of demilitarized land dividing Communist North Korea from the anticommunist South. Along the 38th parallel, it's always 1950.

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