Korean War

The Korean War, occurring between June 25, 1950, and a ceasefire on July 27, 1953, was a war fought in Korea that was divided by the post-World War II Soviet and American occupation zones, with large-scale participation by other countries. The war began with the invasion of capitalist South Korea by forces in communist North Korea in 1950 and ended as a stalemate between the sides in 1953.

The principal support on the side of the North was China, with limited assistance by Soviet combat advisors, military pilots, and weapons. South Korea was supported by United Nations (UN) forces, principally from the United States, although many other nations also contributed personnel. When the conflict began, North and South Korea existed as provisional governments competing for control over the Korean peninsula after the Division of Korea.

In South Korea, the war is often called 6·25, from the date of the start of the conflict or, more formally, Han-guk Jeonjaeng (Korean: 한국전쟁, literally "Korean War"). In North Korea, it is formally called the Fatherland Liberation War (Korean: 조국해방전쟁). In the United States, the conflict was officially termed a police action — the Korean Conflict — rather than a war, largely in order to avoid the necessity of a declaration of war by the U.S. Congress. The war is sometimes referred to outside Korea as "The Forgotten War" because it is a major conflict of the 20th century that garners far less attention than World War II, which preceded it, and the controversial Vietnam War, which succeeded it. In China, the conflict was known as the War to Resist America and Aid Korea (抗美援朝), but is today commonly called the "Korean War" (朝鮮戰爭, Chaoxian Zhanzheng).^[6]

Background

Japanese occupation

Japan occupied strategically important parts of Korea in the early days of the Russo-Japanese War (February 4, 1904 to September 5, 1905) as part of Japan's early emergence as an imperialist power. The Japanese occupied the peninsula against the wishes of the Korean government, gradually expanded their control over local institutions and finally annexed Korea in August 1910.[3]

Korea remained a Japanese colony until the end of World War II in 1945. On August 6, 1945, the Soviet Union, in keeping with a commitment asked for by the United States, declared war on the Japanese Empire and on August 8 began an attack on the northern part of the Korean peninsula. As agreed on with the United States, the USSR halted its troops at the 38th parallel. President Harry S. Truman ordered the landing of U.S. troops in the south.^[7]

Post-WWII Division of Korea

With only weeks to live, Franklin D. Roosevelt made his way to the Yalta Conference in February 1945. Yalta would be FDR’s last great mark on American history. Russian Premier Joseph Stalin called for “buffer zones” in both Asia and Europe.^[8] Stalin had become increasingly cautious after the war because the allies had not opened a second front to offset German advances during the war. The cost had been millions of Russian lives. Stalin believed that Russia should have pre-eminence in China, and in return he would enter into the war "two to three weeks after the surrender of Germany."^[9]

On August 10, 1945, with the Japanese surrender imminent, no one knew where the Russians would stop. A month earlier, some of General George Marshall’s advisors had suggested a demarcation line at the 38th parallel. Dean Rusk (U.S. Secretary of State 1961-69) would later comment that the military was “faced with the scarcity of U.S. forces immediately available and time and space factors which would make it difficult to reach very far north before Soviet troops could enter the area.”^[10]

The Soviets accepted this line with little question. Japanese forces north of that line would surrender to the Soviet Union, and those to the south to the United States. Thus, without consulting the Korean people, the two major powers divided the Korean peninsula into two occupation zones, thereby putting into place the foundation for the eventual civil war. Although later policies and actions contributed to Korea's division, the United States did not envision this as a permanent partition.^[11]

In December 1945, the United States and the Soviet Union agreed to administer the country temporarily in place of the Koreans. Subsequently, both the US and the USSR established Korean-led governments in their respective halves, each one favorable to their respective country's political ideology.

In an election that was UN-sanctioned but widely seen as corrupt^{[citation needed]}, the American-administered south saw the defeat of a left-wing and popular group of political leaders that had been active years before the end of the war. The government that emerged was led by anti-Communist Syngman Rhee, a Korean who had lived outside of Korea for over three decades. The south's left-wing parties boycotted the elections in part to protest U.S. support for Rhee and its suppression of indigenous political movements. The Soviets, in turn, approved and furthered the rise of a Communist government in the North. Bolstered on the one hand by his history as an anti-Japanese fighter and on the other by his connections with the Soviet Union, Kim Il-Sung rose to become leader of this new government.

The Allies had said Korea would be a unified, independent country under an elected government but failed to specify the details and seemed more concerned with winning the opening round of the Cold War than with fulfilling the wishes of the Korean people.^[12] In 1949, both Soviet and American forces withdrew.

South Korean President Syngman Rhee and North Korean General Secretary Kim Il-Sung were each intent on reuniting the peninsula under his own system. Partly because of Soviet tanks and heavy arms, the North Koreans were the ones able to go on the offensive, while South Korea, with only limited American backing, had far fewer options. The American government believed at the time that the Communist bloc was a unified monolith, and that North Korea acted within this monolith as a pawn of the Soviet Union Thus, the United States portrayed the conflict in the context of international aggression rather than a civil war. (Kim Il-Sung, operating with massive Soviet assistance, was responsible for the attack of the South.)

Opening of the Civil War

Rhee and Kim competed to reunite the peninsula, conducting military attacks along the border throughout 1949 and early 1950.^[13] The North, however, armed with Soviet tanks, changed the nature of the war from border skirmishes to a full-scale civil war.

On January 12, 1950, United States Secretary of State Dean Acheson said America's Pacific defense perimeter was made up of the Aleutians, Ryukyu, Japan, and the Philippines, implying that America might not fight over Korea. Acheson said Korea's defense would be the responsibility of the United Nations.^[14]

In mid 1949, Kim Il-Sung pressed his case with Joseph Stalin that the time had come for a reunification of the Korean peninsula. Kim needed Soviet support to successfully execute an offensive far across a rugged, mountainous peninsula. Stalin,, as leader of the communist bloc, refused permission, concerned with the relative lack of preparedness of the North Korean armed forces and with possible U.S. involvement.

Over the following year, the North Korean leadership molded its army into a formidable offensive war machine modeled partly on a Soviet mechanized force but strengthened primarily by an influx of Koreans who had served with the Chinese People’s Liberation Army since the 1930s. By 1950 the North Korean military was equipped with outdated Soviet weaponry, yet it enjoyed substantial advantages over the Southern forces in virtually every category of equipment. After another visit by Kim to Moscow in March and April 1950, Stalin approved an attack.

Korean War (1950–1953)

North Korean attack

The North Korean army struck in the pre-dawn hours of Sunday, June 25, 1950, crossing the 38th parallel behind a firestorm of artillery.^[15]

Equipped with 150 Soviet-made T-34 tanks, the North Korean military began the war with about 180 aircraft, including 40 YAK fighters and 70 attack bombers. The navy was inconsequential. The most serious weakness was its lack of a reliable logistics system for moving supplies south as the army advanced. (In practice, it forced thousands of Korean civilians to hand-carry supplies, many of whom later died in American air attacks.)

Nevertheless, the North's well-planned attack with about 135,000 troops achieved surprise and quick successes.^[16] North Korea attacked many key places including Kaesŏng, Chuncheon, Uijeongbu and Ongjin.

Within days, South Korean forces, outnumbered, outgunned, and often of dubious loyalty to the southern regime, were in full retreat or often defected en masse to the North. As the ground attack continued, the North Korean Air Force conducted bombing on Kimpo Airport near Seoul. North Korean forces occupied Seoul on the afternoon of June 28. But the North's hopes for a quick surrender by the Rhee government and the disintegration of the South Korean Army went up in smoke when foreign powers intervened. They did not expect the war to last long enough for American intervention, so there were no significant defenses prepared against American air attacks.

The South Korean Army had 65,000 soldiers armed, trained, and equipped by the U.S. military, and as a force was deficient in armour and artillery. There were no large foreign combat units in the country when the civil war began, but there were large American forces stationed in nearby Japan.^[17]

Western Reaction

The invasion of South Korea came as a surprise to the United States and other western powers; in the preceding week, Dean Acheson of the State Department had told Congress on June 20 no such war was likely. Contacted hours after the invasion had begun, Truman was convinced the initial stages of World War III had commenced.

The same day the civil war had officially begun (June 25), the United Nations immediately drafted a resolution, which was unanimously passed in the Security Council since the Russian ambassador was boycotting the UN at the time. This led to direct action by the United States and other U.N. members. The Resolution [4]called for three things:

• for all hostilities to end and North Korea to withdraw to the 38th Parallel;
• for a U.N. Commission on Korea to be formed to monitor the situation and report to the Security Council;
• for all U.N. members to support the United Nations in achieving this, and refrain from providing assistance to the North Korean authorities.

Later, debates would arise over the legality of this resolution since it sponsored U.N. intervention into a civil war. Though the resolution passed, it is thought that had the USSR not been boycotting the UN at the time, the Soviets likely would have used their veto to cancel the resolution.

American action was taken for a number of reasons. Truman, a Democratic president, was under severe domestic pressure for being too soft on communism by, among others, Republican senator Joseph McCarthy. Especially outspoken were those who accused the Democrats of having lost China to the communists. The intervention also was an important implementation of the new Truman Doctrine, which advocated the opposition of communism wherever it tried to expand. The lessons of Munich in 1938 also influenced the American decision, leading them to believe that appeasing aggressive states would only encourage further expansion.

Instead of pressing for a congressional declaration of war, which he regarded as too alarmist and time-consuming when time was of the essence, Truman went to the United Nations for approval. (He would later come under harsh criticism for not consulting Congress before sending troops.)

Thanks to a temporary Soviet absence from the Security Council — the Soviets were boycotting the Security Council to protest the exclusion of People's Republic of China (PRC) from the UN — there was no veto by Stalin and the (Nationalist-controlled) Republic of China government held the Chinese seat. Without Soviet and Chinese vetoes, and with only Yugoslavia abstaining, the UN voted to aid South Korea on June 27. U.S. forces were joined by troops from 15 other U.N. members: Canada, Australia, New Zealand, Britain, France, South Africa, Turkey, Thailand, Greece, the Netherlands, Ethiopia, Colombia, the Philippines, Belgium, and Luxembourg.

The Soviet Union and its allies, however, challenged the resolution on grounds of illegality since a permanent member of the council (Soviet Union) was absent from the voting. The North Korean government also did not concur. In 1950, A Soviet resolution calling for an end of hostilities and withdrawal of foreign troops was rejected.^[18]

Although American opinion was solidly behind the venture, Truman would later take harsh criticism for not obtaining a declaration of war from Congress before sending troops to Korea. Thus, "Truman's War" was said by some to have violated the spirit, and the letter, of the United States Constitution. The other foreign powers allied with the United States quickly agreed with American actions, volunteering their support for the intervention. Sixteen nations finally contributed to "UN forces", but the United States provided 50 percent of the ground forces (South Korea provided most of the remainder), 86 percent of the naval power, and 93 percent of the air power.^[19]

U.S. Intervention

Despite the post-World War II demobilization of U.S. and allied forces, which caused serious supply problems for American troops in the region (excluding the United States Marines, the infantry divisions sent to Korea were at 40% of paper strength, and the majority of their equipment was found to be useless), the United States still had substantial forces in Japan relative to the North Korean military with its largely outdated Soviet equipment. These American forces were under the command of General Douglas MacArthur. Apart from British Commonwealth units, no other nation could supply sizable manpower.

On hearing of the outbreak of large-scale hostilities in Korea, Truman ordered MacArthur to transfer munitions to the ROK Army, while using air cover to protect evacuation of U.S. citizens who were fleeing from the advancing North Koreans. Truman did not agree with his advisors who called for unilateral U.S. airstrikes against the North Korean forces but did order the Seventh Fleet to protect Taiwan, thereby ending America's policy of acquiescing to the defeat of the forces of Chiang Kai-Shek. The KMT government (now confined to Taiwan) asked to participate in the war. Their request was denied by the Americans, who felt they would only encourage Chinese intervention.

The first significant foreign military intervention was the American combat unit Task Force Smith, part of the U.S. Army 24th Infantry Division based in Japan. On July 5 it engaged in its first clash with North Korea at Osan and was defeated with heavy losses. The half-strength 24th Division was forced to fall back to Taejeon, which also fell and made General William F. Dean a prisoner of war.

By August, the South Korean forces and the Eighth United States Army had been easily defeated and retreated into a small area in the southeast corner of the Korean peninsula around the city of Pusan. American Eighth Army commander Lieutenant General Walton Walker was able to maneuver his forces to successfully confront the North Koreans as the communists attempted a flanking maneuver instead of concentrating their forces, which might have destroyed U.N. forces in the area.

Nonetheless, by September only the area around Pusan, about 10% of the total Korean peninsula, was still in the hands of the coalition. With the aid of massive American supplies, air support, and additional reinforcements, the U.S. and ROKA forces managed to stabilize a line along the Nakdong River. This desperate holding action became known in the United States as the Pusan Perimeter. Although more U.N. support arrived, the situation was dire for the southern regime and its foreign allies, and it appeared as if the North would unite the peninsula under its government.

Allied forces rally

In the face of fierce North Korean attacks, the allied defense became a desperate holding action called the Battle of Pusan Perimeter by Americans. The failure of North Korea to capture Pusan doomed its hopes for national unification.

American air power arrived in large numbers, flying 40 sorties a day in ground support actions, targeting North Korean forces but also creating widespread destruction among civilians and cities as well. Strategic bombers (mostly B-29s based in Japan) closed most rail and road traffic by day, and destroyed 32 critical bridges necessary not only for the conduct of warfare but the flight of civilians. Trains used by military and civilians alike waited out the daylight hours in tunnels.

Throughout all parts of Korea, the American bombers knocked out the main supply dumps, leveled entire cities and their populations, and eliminated oil refineries and seaports that handled imports such as military supplies, food, and medicine. Naval air power also attacked transportation chokepoints. The North Korean logistics problems grew severe, with shortages of food and ammunition. The North lost half of its invading force, and morale was poor.

Meanwhile, supply bases in Japan were pouring foreign weapons and soldiers into Pusan. American tank battalions were rushed in from San Francisco; by late August, America had over 500 medium tanks in the Pusan perimeter. By early September, UN-ROK forces were vastly stronger and outnumbered the North Koreans by 180,000 to 100,000. At that point, they began a counterattack.^[20]

Liberation of South Korea

Main article: Battle of Inchon

In the face of these overwhelming reinforcements, the North Korean forces found themselves undermanned with weak logistical support, and lacking naval and air support that could match the Americans. In order to alleviate pressure on the Pusan Perimeter, MacArthur, as U.N.commander-in-chief for Korea, ordered an amphibious landing far behind the North Korean troops at Inchon.

The violent tides made this an extremely risky operation, but once the American and other U.N. troops gained a foothold on the beach, it was successful. MacArthur initiated his attack with the landing far behind the North Korean lines at Inchon (인천; 仁川). MacArthur had started planning a few days after the war began but had been strongly opposed by the Pentagon. When he finally received permission, MacArthur activated X Corps under General Edward Almond (comprising 70,000 troops of the 1st Marine Division and the Army's 7th Infantry Division (United States) and augmented by 8,600 Korean troops) and ordered them to land at Inchon in "Operation CHROMITE".

The landing was a decisive victory, as X Corps rolled over the few defenders and threatened to trap the main North Korean army. MacArthur quickly recaptured Seoul. The North Koreans, almost cut off, rapidly retreated northwards; about 25,000 to 30,000 made it back.^[21]

Invasion of North Korea

The United Nations troops drove the North Koreans back past the 38th parallel. The American goal of saving South Korea's government had been achieved, but because of the success and the prospect of uniting all of Korea under the government of Syngman Rhee, the Americans - with UN approval - continued the advance into North Korea. This marked a crucial moment in American foreign policy, when the American leaders decided to go beyond simply "containing" perceived communist threats to actual rollback. Other issues included the psychological effects of destroying a Communist nation and the liberation of POWs.

The U.N. forces crossed into North Korea in early October 1950. The U.S. X Corp made amphibious landings at Wonsan and Iwon, which had already been captured by South Korean forces advancing by land. The rest of the U.S. army, along with the South Koreans, drove up the Western side of Korea and captured Pyongyang on October 19. By the end of October the North Korean Army was rapidly disintegrating and the U.N. took 135,000 prisoners.

The U.N. offensive greatly concerned the Chinese, who worried that the UN forces would not stop at the Yalu River, the border between the DPRK and China, and extend their rollback policy into China itself. Many in the West, including General MacArthur, thought that spreading the war to China would be necessary. However, Truman and the other leaders disagreed, and MacArthur was ordered to be very cautious when approaching the Chinese border. Eventually, MacArthur disregarded these concerns, arguing that since the North Korean troops were being supplied by bases in China, those supply depots should be bombed. However, except on some rare occasions U.N. bombers remained out of Manchuria during the war.

The Chinese entry (October, 1950)

The People's Republic of China, fearful of a capitalist Korean state and American military on its border, warned American leaders through neutral diplomats that it would intervene to protect its national security. Truman regarded the warnings as "a bald attempt to blackmail the UN" and did not take it seriously. On October 15, 1950, Truman went to Wake Island for a short, highly publicized meeting with MacArthur. The CIA had previously told Truman that Chinese involvement was unlikely. MacArthur, saying he was speculating, saw little risk. The general explained that the Chinese had lost their window of opportunity to help North Korea's invasion. He estimated the Chinese had 300,000 soldiers in Manchuria, with between 100,000-125,000 men along the Yalu; half could be brought across the Yalu. But the Chinese had no air force; hence, "if the Chinese tried to get down to Pyongyang there would be the greatest slaughter."^[22] MacArthur thus assumed that Chinese were motivated to help North Korea, and wished to avoid heavy casualties.

On October 8 1950, the day after American troops crossed the 38th, Chairman Mao Zedong issued the order to assemble the Chinese People's Volunteer Army. The members of the PVA were actually Chinese regulars from the Chinese People's Liberation Army, called volunteers so that their entry into the war would not seem to indicate a state-to-state war between the US and China.^{[citation needed]} Mao ordered the army to move to the Yalu River, ready to cross. Mao sought Soviet aid and saw intervention as essentially defensive: "If we allow the U.S. to occupy all of Korea… we must be prepared for the US to declare… war with China", he told Stalin. Premier Zhou Enlai was sent to Moscow to add force to Mao's cabled arguments. Mao delayed his forces while waiting for Russian help, and the planned attack was thus postponed from 13 October to 19 October. Soviet assistance was limited to providing air support no nearer than sixty miles (96 km) from the battlefront. The Russian MiG-15s in PRC colors became a serious challenge to the UN pilots. In one area called "MiG Alley" by UN forces, they held local air superiority against the American made F-80 Shooting Stars until newer F-86 Sabres were deployed. The Chinese were angry at the limited support, having assumed that the Soviets had promised to provide full scale air support. The Soviet role was known to the U.S. but they kept quiet so as to avoid widening the conflict and potential nuclear warfare.

The Chinese made contact with American troops on October 25 1950 with 270,000 PVA troops under the command of General Peng Dehuai, much to the surprise of the UN who had ignored evidence that such a massive force existed. However, after these initial engagements, the Chinese forces pulled back into the mountains. UN leaders saw the withdrawal as a sign of weakness, and greatly underestimated the Chinese fighting capability. The UN forces thus continued their advance to the Yalu river, ignoring stern warnings given by the Chinese.

In late November, the Chinese struck in the west, along the Chongchon River, and completely overran several South Korean divisions and successfully landed a heavy blow to the flank of the remaining UN forces. The resulting defeat of the U.S. Eighth Army was the longest retreat of any American military unit in history.^[23] In the east, at the Battle of Chosin Reservoir, a 30,000 man unit from the U.S. 7^th Infantry Division was also unprepared for the Chinese tactics and was soon surrounded, though eventually managed to flee the encirclement after suffering over 15,000 casualties. The US Marines were also defeated at the Chosin Reservoir and forced to retreat after inflicting heavy casualties on six Chinese divisions.^[24]

The US forces in northeast Korea who had rushed northwards with great speed only a few months earlier, were now forced to race southwards with even greater speed and form a defensive perimeter around the port city of Hungnam, where a major evacuation was being carried out in late December 1950. Facing complete defeat and surrender, 193 shiploads of American men and material were evacuated from Hungnam Harbor, and about 105,000 soldiers, 98,000 civilians, 17,500 vehicles, and 350,000 tons of supplies were shipped to Pusan in orderly fashion. As they left, the American forces blew up large portions of the city to deny its use to the Communists, depriving many Korean civilians of shelter in the dead of winter.^[25]

Fighting across the 38th Parallel (Early 1951)

In January 1951, the Chinese and North Korean forces struck again in their 3rd Phase Offensive (also known as the Chinese Winter Offensive). The Chinese repeated their previous tactics of mostly night attacks, with a stealthy approach from positions some distance from the front, followed by a rush with overwhelming numbers, and using trumpets or gongs both for communication and to disorient their foes. Against this UN forces had no remedy, and their resistance crumbled; they retreated rapidly to the south (referred to by UN forces as the “bug-out”).Seoul was abandoned, and was captured by Communist forces on the 4 January, 1951.

To add to Eighth Army's difficulties, General Walker was killed in an accident. He was replaced by a World War II airborne veteran, Lieutenant General Matthew Ridgway, who took immediate steps to raise the morale and fighting spirit of the battered Eighth Army, which had fallen to low levels during its retreat. Nevertheless, the situation was so grim that MacArthur mentioned the use of atomic weapons against China, much to the alarm of America's allies.

UN forces continued to retreat until they had reached a line south of Suwon in the west and Wonju in the center, and north of Samchok in the east, where the front stabilized. The PVA had outrun its supply line and was forced to recoil. The Chinese could not go beyond Seoul because they were at the end of their logistics supply line--all food and ammunition had to be carried at night on foot or bicycle from the Yalu River.

In late January, finding the lines in front of his forces were deserted, Ridgway ordered reconnaissance in force, which developed into a full-scale offensive, Operation Roundup. The operation planned to proceed gradually, to make full use of the UN's superiority in firepower on the ground and in the air; by the time Roundup was completed, in early February, UN forces had reached the Han River, and re-captured Wonju.

The Chinese struck back in mid-February with their Fourth Phase Offensive, from Hoengsong in the centre against IX Corps positions around Chipyong-ni. A short but desperate siege there fought by units of US 2nd Division, including the French battalion, broke up the offensive; in this action the UN learned how to deal with Chinese offensive tactics and be able to stand their ground.

Roundup was followed in the last two weeks of February 1951,with Operation Killer, by a revitalized Eighth Army, restored by Ridgway to fighting trim. This was a full- scale offensive across the front, again staged to maximize firepower and with the aim of destroying as much of the PVA and NKPA as possible. By the end of Killer, I Corps had re-occupied all territory south of the Han, while IX Corps had captured Hoengsong.

On 7th March, 1951, Eighth Army pushed forward again, in Operation Ripper, and on 14th expelled the North Korean and Chinese troops from Seoul, the fourth time in a year the city had changed hands. Seoul was in utter ruins; its prewar population of 1.5 million had dropped to 200,000, with severe food shortages.^[26]

MacArthur was removed from command by President Truman on April 11 1951 for insubordination, setting off a firestorm of protest back in the States. The new supreme commander was Ridgway, who had managed to regroup UN forces for the series of effective counter-offensives. Command of Eighth Army passed to General James Van Fleet.

A further series of attacks slowly drove back the Communist forces, such as operations Courageous and Tomahawk, a combined ground- and air-assault to trap Communist forces between Kaesong and Seoul. UN forces continued to advance until they reached Line Kansas, some miles north of the 38th parallel.

The Chinese were far from beaten, however; In April 1951 they launched their Fifth Phase Offensive, ( also called the Chinese Spring Offensive ) This was a major effort, involving 3 Field Armies ( up to 700,000 men ). The main blow fell on I Corps, but fierce resistance in battles at the Imjin river and Kapyong, blunted its impetus, and the Chinese were halted at a defensive line north of Seoul (referred to as No-Name Line.

A further Communist offensive in the east against ROK and X Corps on the 15 May also made initial gains, but by the 20th the attack had ground to a halt. Eighth Army counterattacked and by the end of May had regained Line Kansas.

The decision by UN forces to halt at Line Kansas, just north of the 38th Parallel, and not to persist in offensive action into North Korea, ushered in the period of stalemate which typified the remainder of the conflict.

Historian Bevin Alexander had this to say about Chinese tactics in his book How Wars Are Won:

The Chinese had no air power and were armed only with rifles, machineguns, hand grenades, and mortars. Against the much more heavily armed Americans, they adapted a technique they had used against the Nationalists in the Chinese civil war of 1946–49. The Chinese generally attacked at night and tried to close in on a small troop position — generally a platoon — and then attacked it with local superiority in numbers. The usual method was to infiltrate small units, from a platoon of fifty men to a company of 200, split into separate detachments. While one team cut off the escape route of the Americans, the others struck both the front and the flanks in concerted assau