The Korean War (1950-53) was a major Cold War military clash fought up and down the peninsula of Korea, finally leading to a stalemate in 1950 that restored the boundaries to nearly what they were at the start, along the 38th parallel. The war was initiated by Kim Il-sung of the Democratic People's Republic of Korea (North Korea), with assistance from China and the Soviet Union were arrayed against the Republic of Korea (South Korea), supported by the United States of America and a multinational United Nations force.
The war began with an invasion by North Korea in June 1950, followed by an unexpected American entry. North Korean forces had pushed the South Koreans and Americans back into a small perimeter around the port of Pusan. In September 1950, an amphibious landing at Inchon, followed by a breakout from the Pusan Perimeter, turned the tide. The North Korean People's Army (NKPA) disintegrated as the allies moved north, with UN approval, to unify the country. Unexpectedly the Chinese then sent in large numbers of infantry, and in the bitter cold of November-January 1950-51 pushed the UN forces out of the north. Communist supply lines were fragile, especially in the face of heavy American bombing, so the lines stabilized close to the 38th parallel in 1951. Two more years of static warfare followed, with the issue of returning reluctant Communist prisoners of war held by the UN the major sticking point. Finally an armistice was reached in summer 1953; the prisoners were exchanged and fighting ended in an uneasy truce that continues into 2008.
The war was limited in size and scope, but casualties were heavy on both sides. In the U.S., the political consequences of the war contributed to the defeat of the Truman administration and his Democratic party in the 1952 election of General Dwight D. Eisenhower, the Republican candidate who promised to end the war. For Americans and Chinese it is a "forgotten war", neglected on the timeline between the twin cataclysms of World War II and Vietnam.  For the Koreans it is the central event of their modern history, and efforts to reunify the land continue.
Historically an independent nation, Korea had been seized by Japan in 1910 and cruelly treated as a colony. The Koreans came to hate the Japanese violently, and were overjoyed at their liberation by Soviet and American soldiers in September, 1945. The division of Korea was set at the Potsdam Conference in July 1945, when Joseph Stalin for the Soviet Union and Harry S. Truman for the U.S. agreed to divide the Japanese-controlled Korean peninsula at the 38th parallel. The Korean people wanted to throw off the Japanese and become united, but the second goal was only vaguely promised at Yalta. The assumption was that postwar amity between the USSR and US would lead to a reasonable solution at some indefinite future time. As the Cold War started, the two superpowers sponsored rival governments, Communist in the North and anti-communist in the South. Given the fierce determination of Koreans to unite their homeland, a civil war was inevitable.
Ruling the south was a right-wing government headed by Syngman Rhee, who had been converted to Christianity during his exile, and then earned a PhD in theology from Princeton University. Although Rhee's authoritarian regime crushed pro-Communist uprisings, he did allow the emergence of a civil society in the south. That is, there were multiple independent sources of thought and power, like corporations, local businesses, universities and churches, in contrast to the north where the Communist party controlled all activity down to the neighborhood level.
Kim sought support from his two northern neighbors, Mao's China and Stalin's Soviet Union. At the time Washington considered both Mao and Kim to be Stalin's puppets; historians now see China as a largely independent actor, but Kim was heavily dependent on the Soviets. Until the release of many Soviet and Chinese documents in the 1990s, historians believed that Mao did not want war with the US, and intervened in Korea only when the onrushing UN armies appeared poised within weeks to cross the Yalu and begin rolling back Communism inside China. The new evidence clearly shows that Mao's highest goal was to drive capitalism/America out of Asia. China began preparations to enter Korea in July and August, 1950, well before the Inchon landings. Mao, who had just taken control of China needed to "save face"; he also feared counterrevolutionary forces inside China and wanted to fire up revolutionary ardor through a war. By encouraging anti-imperialistic revolutionary nationalism and socialist solidarity at home, he thought that intervention in Korea would help maintain the momentum and purity of his revolution within China. 
Kim, Stalin and Mao were all committed to their own versions of aggressive, anti-western Marxist-Leninism. Kim was overconfident of success and afraid of falling hopelessly under Chinese influence, so he initially refused Chinese aid and would not openly share information with Beijing. He reversed course when his army collapsed and the UN invaded in October, 1950. Even so, he repeatedly bickered with the Chinese regarding tactics, railroad use, negotiations with the enemy, and the makeup of the Korean-Chinese joint command structure, and the Soviets sometimes had to intervene to force an agreement.
Both Mao and Stalin were committed to revolution in Asia, and both concluded after America's failure to send troops into the Chinese Civil War that Washington would ignore an invasion of South Korea. Mao advised North Korean leaders that "solely military means are required to unify Korea. As regards the Americans, there is no need to be afraid of them. The Americans will not enter a third world war for such a small country.".
Most of the 20 million Koreans in the South and the 10 million in the North were subsistence farmers living in the western half of the peninsula. Travel was a chore in the west (except on the good railroad system), and quite difficult in the mountainous east. The industrial level was low and the people were extremely poor. Nevertheless Kim built a powerful military machine in the North.
The US Army considered the peninsula indefensible and, in line with severe budget restraints, removed its soldiers in 1949. It left small arms and ammunition behind for ROK, the new South Korean army, but no tanks, no warplanes and no medium or heavy artillery. The North Koreans were much better armed, having leftover Japanese weapons, and second-hand equipment sold them by Moscow. Frustrated that internal subversion had not toppled the anticommunist government in Seoul, Kim decided to invade.
North Korea invades
Kim ordered the (North Korean People's Army (NKPA) to invade on June 25, 1950. Spearheading 9 divisions with 80,000 men were elite units with 100-150 excellent Soviet T-34 battle tanks, backed up by 100 aircraft. The South Koreans had only 100,000 soldiers (65,000 in combat roles) and little equipment. Moscow's military experts figured that the North had a 2:1 advantage over the South in troops, 2:1 in artillery; 7:1 in machine guns; 6.5:1 in tanks; and 6:1 in aircraft--ratios quite adequate for a successful conquest if South Korea received no American help.
The ROK generals were mediocre political appointees; the ROKA lost half its combat effectiveness quickly. The NKPA broke through the four ROK divisions along the border, captured the capital of Seoul on the third day, and kept moving south.
The North Korean general staff quickly lost control of the battle, even though it was winning; its Russian advisors had done a poor job in establishing a command and communication system. Kim expected that Koreans in the south would welcome his invaders and the Seoul regime would vanish overnight. He was wrong--the southerners resisted invasion as best they could, fled to regroup, and supported their government even as the invaders systematically identified and executed anti-communists. Kim, intent on unifying Korea on a Communist basis with himself in charge, apparently ignored the likelihood of UN condemnation and the possibility of American intervention--for example, he made few diplomatic overtures and did not bother to set up anti-aircraft defenses. The Communist divisions and regiments fought with enthusiasm, but made poor use of their artillery and tanks. These weaknesses would prove fatal once they opposed a real army.
U.S. and UN entry
President Harry S. Truman immediately asked General Douglas MacArthur, commander of American forces in Japan, Forces in the Far East, for his evaluation. MacArthur flew to South Korea on June 27. The same day Truman ordered MacArthur to provide air and naval support. MacArthur reported that the ROK (South Korean) forces were too weak to hold.
Truman was as surprised as everyone else but, remembering the dithering in the late 1930s that encouraged Adolf Hitler, he moved fast. Although there were no treaties involved, and the Joint Chiefs of Staff advised against the use of ground forces, he declared that American ground soldiers would fight to save South Korea. He called it a "police action" and legally it was not a war. Truman decided not to ask Congress for a declaration of war or any other official approval--a political blunder that would later cost him dearly. He did go to the United Nations. The Soviet foreign ministry wanted to veto UN intervention, but Stalin--probably astonished that the US decided to resist--rejected the advice and insisted his delegate not take part in the Security Council decision. "We are not ready to fight," Stalin exclaimed, according to the memoirs of his aide Nikita Khrushchev.
Officially the USSR remained neutral throughout the war, although it provided supplies and instructors, and communications intelligence has been declassified that revealed combat pilots speaking Russian. The United Nations Security Council (UNSC) then authorized a UN defense force to repel North Korean aggression and made the US and thus President Truman (as Commander in Chief), its agent to make all its military decisions. President Rhee gave control of his armed forces to the UN, and Truman named MacArthur to the UN command. "The buck stops here," Truman often said. He and Acheson made the decision to intervene under the assumption that Stalin was deliberately probing for weaknesses, and that any sort of appeasement or surrender to aggression would destroy America's credibility and leadership in Europe.
In the entire war the U.S. provided 50% of land, 86% of naval and 93% of UN air power; ROK forces came next, followed far behind by Britain, Turkey, Canada, Australia and ten other nations. Truman vetoed MacArthur's recommendation to use Nationalist Chinese troops and they played no role in the war. No one (especially not the Japanese) wanted an Imperial Japanese Army marching in Korea and so Japan's role was as a supplier and staging base, a function that helped reinvigorate the Japanese economy.
The containment policy of the Truman administration called for a military response to Communist military invasion, no matter how difficult conditions were. The American entry surprised the Communists; North Korea realized it was unequipped to handle the Americans.
On July 19, Truman asked Congress for an emergency defense appropriation of $11 billion. Truman, like Roosevelt before him in 1940, wanted 50,000 war planes built a year. Congress appropriated $8 billion for aircraft production for 1951.
Holding the Pusan perimeter
On July 1, an advance party of 440 American infantrymen from Task Force Smith landed in Korea with the mission of slowing the North Korean juggernaut; on July 5 they were overrun by NKPA tanks, with one third taken prisoner. The war would have many surprises in store for the Pentagon--which had been planning in terms of a global war. The Army's then-current operations guide, Field Manual FM 100-5 (1949) explained the war strategy was for the US to employ its strategic bombers against an enemy's industrial capacity. Forward bases suitable for tactical bombers would then be established. Finally, after many months for buildup, training and shipment, heavy assault forces amply supplied with artillery and armor would invade the enemy homeland and force surrender. The Pentagon had ignored the possibility of a limited war in which critical targets were off limits, only a fraction of the nation's firepower could be used, and the goal was diplomatic advantage, not victory on the battlefield or conquest of an enemy nation.
Perhaps it did not matter, for the US was not ready to fight any kind of war in 1950. because there were only 110,000 combat troops in 10 understrength Army and Marine divisions; about the same as North Korea. Four of the combat divisions (comprising the Eighth United States Army under General Walton Walker) were nearby in Japan. Their mission had been to guarantee there would be no revival of Japanese militarism. Although most officers and NCOs had extensive combat experience, occupation duty had left them soft, overweight and unready for combat. Giving the excuse there were no open spaces, the divisions had completely neglected large formation training. Not expecting to fight anywhere, the Eighth had closed down its two corps headquarters, which were necessary for directing combat. Infantry regiments lacked their third (reserve) battalion. Only three tanks worked, and units had not trained with them. Equipment consisted of rusting World War II items hurriedly scrounged from supply dumps; salvage teams went to old Pacific battlefields like Iwo Jima to find replacement parts. 2,75" bazooka shells of limited effectiveness in the Second World War were more ineffective against Russian armor in Korea.
Advance units rushed to Korea were relentlessly pushed back by the NKPA. Some units fought well; however the 34th US Infantry Regiment fell apart and performed badly. The victors of World War II were being rolled back by a motivated army, with poor logistics, from a small impoverished country. Truman was forced to increase the draft, issuing a call for 50,000 men in September; they would not be ready for combat for many more months. The entire 33,000-member Marine Corps Reserves was called up in order to rebuild the First Marine Division for combat. The President risked public outrage when he decided not call up organized Army Reserve units, but rather to reactivate World War II veterans who had nominal membership in the "Inactive Reserves." MacArthur needed four National Guard divisions in December; Truman called them to federal service reluctantly because their involvement would affect communities across the land, and would necessitate Congressional approval. The unpreparedness forced Truman to fire his incompetent Defense Secretary, Louis Johnson, and recall the old workhorse retired General George Marshall from retirement. Marshall, aged 70 was long past his prime, but he answered the summons to duty and served as a figurehead, with his deputy (and successor) Robert Lovett in actual control.
Tactical air power
Outnumbered American and ROK troops had the mission to delay the enemy until reinforcements could arrive from Japan and the States. They fell back to a small perimeter around the port of Pusan, where their lines held firm. A critical factor was the US Far East Air Force (FEAF), commanded by George Stratemeyer. Tactical air power had been one of the decisive weapons of World War II, but it had been cut over 90% in size, a victim of very tight budgets and a commitment by top Air Force officials to a doctrine of strategic bombing.
Simultaneously, the US Navy blockaded the coast line and provided Navy, Marine and Royal Navy tactical air sorties from two aircraft carriers. Enemy forces had to hide during the daytime; they could only attack at night. The Air Force relearned the techniques of tactical air power; together with Navy and Marine air forces they knocked out of action 50,000 invading troops, and over half of their tanks, trucks and artillery. Marine air forces always had emphasized close support.
Fighter pilots were trained to gain air supremacy so the bombers could get through, not to undertake ground attacks on supply lines or soldiers. Worldwide the Air Force had 48 combat wings of which 30 were in FEAF. The main weapon comprised 365 Lockheed F-80 "Shooting Star" jet fighters, with a combat radius of only 225 miles, barely enough to cover South Korea. FEAF promptly seized air supremacy from the North Korean Air Force, and began systematic tactical bombing targeted at the enemy's long, vulnerable supply line. Hundreds of 1945-vintage P-51 Mustangs piston fighters (renamed "F-51") were taken from storage and shipped by carrier to FEAF.
When the war started in June 1950, the aircraft carrier USS Valley Forge (CV-45) was in the Philippines, as part of Carrier Division 3 under Rear Admiral J.M. Hoskins. The ships initially, a light cruiser and eight destroyers, deployed to Okinawa, since it was unclear if the conflict would spread beyond Korea. Joining a Royal Navy unit of the carrier HMS Triumph, a heavy cruiser and two destroyers, the UK-US squadron became Task Force 77 of the United States Seventh Fleet.
On July 3, the British carrier launched a before-dawn strike at the North Korean airfield at Haeju, defending the capital, Pyongyang, from the south. Slightly later, the faster Valley Forge launched a strike at the airfield in the capital proper. Later in the day, they struck at railroad facilities. In the following days, they conducted armed reconnaissance and more strikes against railroad facilities.  Valley Forge operated F4U Corsairs and AD Skyraiders, both propeller-driven. She also flew early jet fighters, the F9F Panther. Landing problems for the jets became evident with the straight deck of the carrier. 
Navy and Marine F4U Corsair and A1H Skyraider propeller-driven aircraft delivered excellent close air support, although could make little contribution to air defense. These aircraft could carry a heavy load of weapons, and had much more time in the air than the fuel-hungry jets.
The most severe shortage was in photographic intelligence; no reserve units had been created to preserve this valuable wartime skill, and the upshot would prove to be a major disaster.
The North Koreans, stretched thin, with very poor logistics, outnumbered, outgunned, and lacking an air force or navy, were highly vulnerable. MacArthur had far more soldiers and firepower in Korea than the enemy, plus complete air supremacy and unhindered logistics. He had no intention of merely holding a small enclave. He planned a masterstroke to win the war and roll back Communism throughout the peninsula. His plan was an amphibious invasion far behind the North Korean lines at Inchon on the west coast of South Korea, just west of the capital city of Seoul. He started planning a few days after the war began. Working closely with admirals who were masters at organizing amphibious landings, he and his chief of staff Major General Edward Almond hurriedly readied the First Marine Division for an invasion. MacArthur said his idea was for "a turning movement deep into the flank and rear of the enemy that would sever his supply lines and encircle all his forces south of Seoul."
The Inchon landing was an audacious scheme--not least because of the very high tides at Inchon--and it alarmed the Marine commanders and especially the top brass at the Pentagon. MacArthur's amazing personal persuasiveness converted the skeptics who met with him in Tokyo, but Washington still said no. The Joint Chiefs of Staff were afraid something would go wrong, including J. Lawton Collins (Chief of Staff of the Army), Hoyt Vandenberg (chief of Staff of the Air Force), and especially the Chairman of the Joint Chiefs of Staff, Omar Bradley. Their careers had been defined by victory in huge land battles in Europe; they consequently underestimated the Navy and Marines, distrusted MacArthur, and were baffled by his thesis that Asia was just as vital to America's future as Europe. They had been reluctant to defend Korea in the first place. MacArthur received vigorous support from Chief of Naval Operations Forrest Sherman, and finally won JCS approval for his plan to win the war outright.
MacArthur activated X Corps under General Almond to land at Inchon in Operation CHROMITE. X Corps comprised 70,000 troops of the 1st Marine Division, and the 7th Army division (augmented by 8,600 Korean troops). Almond led 25,000 Marines and soldiers to a successful landing on 15 September 1950; casualties were 200, with 21 killed. Inchon was immediately hailed as one of the most brilliant and decisive tactical moves in military history as X Corps rolled east over the few defenders and threatening to trap the main North Korean army. MacArthur quickly recaptured Seoul. The North Koreans, almost cut off, raced north; about 25,000 to 30,000 made it back. 
The combat capability and logistics of the NKPA had already been ruined by air power; now it were in imminent danger of encirclement. Kim Il-sung, under the illusion that he was about to conquer the Americans at Pusan, kept up his hopeless attack. The Russians demanded he retreat and finally, after stalling a week, Kim turned his invaders north and desperately raced back home under the steady hail of bombs. He rescued his all-important political cadres, leaving behind nearly all their equipment and most of their soldiers. The Communists did defend Seoul, at least long enough to massacre thousands of civilian political enemies and delay the closing of the trap. 20,000 North Koreans made a last ditch stand in Seoul until they were killed or captured; the capital was recaptured on September 27. American and ROK troops reached the 38th parallel in early October. Just 90 days after the invasion the battle of South Korea was a smashing UN victory. Victory appeared to be in sight, as the Communists retreated and MacArthur's staff told of sending the men home by Christmas. The war, however, had just begun round three.
Rollback or containment?
The initial objective of Truman and his top advisor Secretary of State Dean Acheson was to repel the North Korean invasion, restore the Rhee regime, and contain Communism along the 38th parallel. Containment was the administration's main Cold War policy. However, after victory at Inchon, Truman and Acheson changed to "rollback" — that is expelling all Communist forces and unifying the peninsula, with elections to be held by the UN. In the State Department George F. Kennan and his Policy Planning Staff insisted that even though the USSR was behind the war, it was nevertheless a civil conflict and containment policy did not apply; Kennan was ignored. And UN forces raced north across the 38th, with official UN approval. MacArthur previously had suggested that Korea had little strategic importance; after Inchon he advocated unifying Korea through annihilating the North Korean army. After Chinese intervention Truman and Acheson reverted to a containment position, arguing rollback was now too expensive. However in early 1951, MacArthur proposed to continue the rollback strategy by cutting off Chinese reinforcements (by bombing their bases north of the Yalu River, inside China), and by using fresh soldiers on offer from the anti-Communist Chinese government in Taiwan. Truman, Acheson and the Joint Chiefs of Staff rejected this plan as "the wrong war" -- that is, the real war was against the Soviets--and fired MacArthur when he kept up his advocacy.
MacArthur put General Walton Walker in charge of the main US force, the Eighth Army, and loaded Almond's X Corps for a landing at Wonsan on the east coast of North Korea. Almond, who had commanded the all-black 92nd infantry division in Italy, worked vigorously to recruit Korean troops. Some Korean Augmentation to the United States Army (KATUSA) soldiers, not necessarily English-speaking, were attached directly to US Army companies. Others went into the reconstituted ROK I Corps (part of Eighth Army), which raced across the border on October 1 and liberated Wonsan. As the Marines landed on the Wonsan beaches, Bob Hope invited them to his big show that night--he had arrived overland with the fast-marching Korean army. In the west the Eighth Army crossed the 38th parallel on October 9, two days after the UN authorized reunification of Korea. It raced north, capturing the enemy capital of Pyongyang and sending tens of thousands of prisoners to POW camps in the rear. On Nov 21 advance elements reached the Yalu River, which marked the border with China.
As early as July 5, 1950, as American forces began arriving, Stalin recommended to Chinese prime minister Zhou Enlai that China be ready to intervene with 9 divisions, and promised Soviet air support. China, fearful of a capitalist Korean state on its borders, warned neutral diplomats in India that it would intervene. Truman regarded the warnings as "a bald attempt to blackmail the UN". On October 15, 1950, Truman went to Wake Island in mid-Pacific for a short, highly publicized meeting with MacArthur. The CIA had previously told Truman that Chinese had the resources to intervene but was unlikely to do so. MacArthur, saying he was speculating, saw little risk. The general explained that the Chinese had lost their window of opportunity to help the invasion. He estimated the Chinese had 300,000 soldiers in Manchuria, with between 100,000 and 125,000 men along the Yalu; half could be brought across the Yalu River. But the Chinese had no air force; hence, "if the Chinese tried to get down to Pyongyang there would be the greatest slaughter."  MacArthur basically assumed that Chinese wished to avoid heavy casualties. However Truman did not allow MacArthur to fly reconnaissance planes over Chinese airspace north of the Yalu, and thus the huge Chinese buildup was underestimated.
In Beijing, Mao Zedong and his Communist high command were in a quandary. They had just defeated Chiang Kai-shek's Nationalists, who been supported financially by the hated Americans. Chiang had fled with several hundred thousand troops to the island of Formosa (Taiwan); the logical next step for Mao would be an invasion of Taiwan that would forever end the risk of an anti-communist comeback.Striving for international recognition, Mao was outraged that Chiang was allowed to keep China's seat in the UN. The failure of North Korea's invasion came as a shock; MacArthur's advances meant that hostile capitalistic forces would soon be on China's Yalu boundary, close to the industrial plants of Manchuria. If Korea became integrated into western capitalism, it would provide an alternative model of social and economic development that Communism would have great difficulty matching. Many Korean Communists had fought in the Chinese civil war, and the spirit of worldwide Communist solidarity mandated rescuing Kim. UN reassurances that no harm to China was intended, and that air and ground forces would not cross the Yalu proved irrelevant. Stalin was pushing hard for China's entry, promising munitions; Stalin said, however, that the Soviets were not yet ready to provide air cover. Mao could not tolerate any Americans anywhere in Korea; the peninsula had to be unified under Communist control. Sooner or later, Mao concluded, there would be war between China and the USA--so the question was where to fight: in Korea, in Formosa, in Vietnam? Korea, he decided, provided "the most favorable terrain, the closest communication to China, the most convenient material and manpower backup...and the most convenient way for us to get Soviet support." Peng Dehuai, slated to command the troops, helped sway the Politburo's decision to intervene. 
The dangers to China were enormous: at best, severe damage to the economy and permanent American hostility, at worst an all-out war with the Yankee superpower that might terminate the fledgling Communist experiment. Washington misread Mao's intentions: it concluded that China was only bluffing, and failed to issue a stiff warning against intervention. Stalin had approved Kim's invasion beforehand, sold North Korea some munitions, provided military advisors, and helped mine the harbor at Wonsan. Russia also sold thousands of its first generation MiG-15 jet fighters to the Chinese. Moscow strongly supported the war but was reluctant to become too directly engaged--Stalin feared the American Air Force. After the Americans landed at Inchon he ordered his air force to prepare to send combat units and ground support units to defend the North Korean capital of Pyongyang. He sent senior Russian generals to give advice to (or maybe take charge of) North Korea's faltering army. At a critical point in the first two weeks of October, 1950, with Chinese troops poised on the border but Beijing hesitating whether to unleash them, Stalin pushed Mao hard, saying a decisive entry now was the best way China could recover Taiwan and prevent Japan from militarizing. He claimed the U.S. was unprepared for a big war and even with its allies was weaker than the USSR and China. Stalin exhorted, "If a war is inevitable, then let it be waged now and not in a few years when Japanese militarism will be restored." Stalin was willing to let China play the dominant role in Korea because it was too dangerous for the USSR. Later Moscow orchestrated a worldwide propaganda campaign preaching hatred and fear of the Americans, with special emphasis on false charges that the US had unleashed inhumane biological weapons.
In late September, a week or two after the Inchon landing, Mao had ordered 12 divisions ready to invade Korea. When Russia failed to provide the aviation that Stalin had promised, Mao realized his small air force would be unable to challenge American aircraft, training, and infrastructure. His strategy was to endure the air attacks (including possible American raids on Chinese cities), and overwhelm MacArthur by 4-to-1 in ground combat soldiers, and (if Stalin provided the howitzers) by 3 to 2 in artillery. Stalin, though repeatedly urging Mao to attack, was late in providing the equipment.
China's intervention proved a dreadful mistake; while there were no air raids on Chinese cities, China's "volunteers" suffered upwards of a million casualties.Cite error: Closing
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<ref> tag The ROK units crumbled, and the Eighth Army, outnumbered 2 to 1, could not hold. Unable to help or be assisted by X Corps, which was across the mountains, Eighth Army began a 130-mile forced retreat that ended below Seoul. Casualties were moderate but morale had been shattered and the retreating units abandoned vast stores of supplies and weapons. In worse trouble was X Corps on the east, hit by an additional 120,000 soldiers in 12 Chinese divisions. Its ROK units also disintegrated, and it was nearly encircled at Chosin Reservoir. The bitterly cold November weather and heavy snow caused motors to freeze up and weapons to jam. Frostbite was common. (On the Chinese side, an amazing lack of winter gear or even blankets caused the loss of tens or even hundreds of thousands of soldiers.) Ordered to relieve pressure on the Eighth Army 50 miles to the west, 3,200 men of the 7th Infantry's Task Force MacLean (also known as Task Force Faith) counterattacked east of Chosin. To their horror, they crashed into the CCF Ninth Army Group, over 100,000 men strong. The task force was annihilated, with fewer than 400 survivors in one of the worst defeats ever suffered by an American unit. Many blamed Almond's brashness, tactical incompetence, and callousness, others said MacArthur was to blame for splitting his forces.
The First Marine Division was surrounded by 8 divisions at Chosin and had to "attack in another direction," pausing only to evacuate 4,300 casualties by air. After a two-week retreat, X Corps reached safety, reporting some 700 dead, 3,300 wounded, 4,800 missing (most were captured), and 7,300 frostbite victims. The Navy then smoothly evacuated X Corps from Wonsan, moving 105,000 UN soldiers, 98,000 civilian refugees, 18,000 vehicles, and 350,000 tons of supplies back to the west, where they became the Eighth Army reserve. At least this was not another Dunkirk or Bataan. MacArthur was given primary responsibility for the debacle, which reflected the downside possibility of his overoptimistic strategy. He thought the Chinese would behave like the Japanese he had demolished so easily in 1944-45; instead they fought like the Germans. He blamed the restrictions imposed by Washington. Some retreat was necessary in the face of the unexpected Chinese attack, but the UN forces fell back too far, and lost too much control; ROK divisions in particular crumbled away. Perhaps a strong defensive line could have been established north of Seoul, but Walker mistrusted the ROK divisions that anchored his right.
Ridgway holds and pushed back
When General Walker died in a jeep accident on December 23, 1950, General Matthew Ridgway, the operations manager for the war based at the Pentagon, flew in to take over the psychologically shattered Eighth Army. MacArthur remained theatre commander, but gave up all operational control. Ridgway, wearing a hand grenade on his uniform, had long complained that GIs nowadays were not up to World War II standards; in a dramatic turnaround, he rebuilt the morale of the UN forces. Ridgway realized the Chinese would not crumple up; they had to be outfought mile by mile, like the Germans he opposed in 1944-45. He stiffened morale and insisted on elemental tactics: such as staying off the roads and controlling the ridges instead. In February and March, 1951, Ridgway launched counterattacks, aptly named "Operation Killer" and "Operation Ripper." Get nicer codenames, the Pentagon said. No, retorted Ridgway. "I am by nature opposed to any effort to 'sell' war to people as an only mildly unpleasant business that requires very little in the way of blood." Seoul, utterly devastated, changed hands a fourth time as UN forces reached near the 38th parallel, and the lines virtually froze in place in late May.
Ridgway's strategy was now attrition, with American technology pitted against Chinese manpower. Avoiding infantry combat, American forces relied on a vast artillery superiority (about 10-1), and heavy use of tactical airpower to cut the supply lines leading to the static battlefront. Chinese capabilities were strictly limited by its logistics problems. Although the Chinese traveled very light, they still needed 50 tons per day per division (compared to 600 tons for the Americans.) Their main supply dumps were just north of the Yalu River, and Washington gave strict orders that no warplanes were to cross that river, lest the war escalate out of control.
The Soviets now introduced their air force, painted in Chinese colors and flown from Chinese air bases by Russian pilots. Several hundred MIG-15 fighters, high-performance Soviet jets with a short range, based just north of the Yalu, provided the first significant Communist air power of the war. The swept-wing MIGs flew circles around the old Mustangs and were faster and more powerful than the straight-wing F-80s "Shooting Star" jets. The slower American jets however had better hydraulics (and so were more maneuverable), and had better cockpit designs (allowing the pilots to see better). This allowed the American pilots to race through their cycle of observation/orientation/decision/action faster than the Russians. Better training plus more sensitive controls and better vision gave the Americans an information advantage that overcame speed and power deficits. The Air Force rushed in 150 North American F-86 swept-wing Sabre jets. They proved slightly better aircraft than the MIGs and the much better trained American pilots quickly controlled the air. Much of the air-to-air combat occurred in "Mig Alley" in far northwest Korea, near the Manchuria airfields. UN pilots claimed 950 kills versus a loss of only 147, but there were many moments (especially in the fall of 1951) when it was feared the Chinese and Soviet enemy might gain air superiority. Three dozen aces--older men with World War II experience--accounted for a third of the kills. Flak downed 1,200 UN tactical bombers and other planes.
The UN air war was primarily one of interdiction of supplies. In defense, the Chinese proved remarkably adept at repairing bridges, and getting maximum advantage from their trucks and ox-carts. They sent in tens of thousands of porters, who every night hand carried 80-100 pound loads on poles or A-frames. (Humans were more efficient than oxen because they ate less and could hide more easily in the daytime.) Using this extremely labor-intensive, high-casualty system they could support 1,000,000 troops along the Yalu, 600,000 through Pyongyang (120 miles south of the Yalu), but only 300,000 at the 38th parallel (175 miles south) and fewer than 200,000 at their point of furthest advance 45 miles south of Seoul (250 miles below the Yalu). So frightening were the continuous UN air attacks that by the time enemy reinforcements reached the front line they were already suffering from combat fatigue. Consequently Ridgway's counterattacks pushed the CCF back to the 38th parallel and a bit further. Finally the Chinese reached equilibrium between its logistics capability and the number of casualties it was willing to endure to teach the Yankees a lesson. Ridgway's success was based on a restoration of morale, aggressive tactics, air supremacy, systematic interdiction of the enemy logistics system, very heavy use of artillery, and a good logistics system to supply UN forces.
Ridgway and Van Fleet had been selected for command because of their aggressiveness, and during the drawn-out peace talks they demonstrated it. Instead of concentrating on logistics, bombers started targeting high value installations, like electric power generating plants, mines, and civilian population centers. The purpose was to make the enemy hurt enough to want to negotiate. Washington, however, refused to allow any attacks on Chinese territory. The ground war had come to resemble the static Western Front of World War I, with both sides dug in and very little movement. The Americans aggressively sent out several thousand patrols a week along its narrow (125-mile) front. Van Fleet increasingly substituted massive artillery barrages for infantry attacks. The Communists went underground in literal fashion to avoid the continuous UN air and artillery barrages. Air raid shelters, command posts, communication links, supply dumps, barracks, even civilian agencies and munitions factories were built into caves and hillsides. Both sides used massive amounts of artillery, which generated a steady stream of casualties. Much more frightful were the battles for specific hills, like Heartbreak Ridge and Pork Chop Hill. They lacked any strategic value, but if the other side attacked they had to be recaptured else prestige would be lost--it was like Verdun (1916) on a mercifully smaller scale. At Heartbreak Ridge in the fall of 1951, the US 2nd Infantry Division blasted away with 700,000 rounds of artillery and mortar shells (not to mention 842 close air support sorties). It suffered 3,700 casualties (half of them by the French battalion), compared to an estimated 25,000 Chinese killed or wounded. It became common practice for all the artillery of a division (72 guns) to fire in support of a twelve-man patrol. The Battle of Pork Chop Hill in spring 1953 was just as bloody, and just as pointless.
Twenty months of useless stalemate had zero impact on the peace talks, but did produce 36,000 Americans killed. Before they decided to intervene, the Chinese had predicted, "A prolonged war of attrition will naturally increase the difficulties of the Korean people but it will increase the difficulties of the American imperialists much more." Indeed, public opinion did not support a war of attrition with no clear goal other than the hazy one of containment, and Truman was forced out of the presidential race in 1952. "Korea has become a meat grinder of American manhood," lamented one Democrat. Eisenhower, by promising to go to Korea personally to solve the stalemate, easily won the mandate from a frustrated electorate.
In the view of public opinion, especially after 1970, the true heroes were the doctors and nurses of the division-level evacuation hospitals and the new corps-level Mobile Army Surgical Hospitals (MASH). While the M*A*S*H film of 1970 and the television characters voiced cynical antiwar sentiments more appropriate to the Vietnam era, the MASH units did indeed save many lives because of their immediate surgical care of wounded soldiers. Medical care, always a long suit of the US military, continued to improve. In World War II 28% of wounded soldiers died; now it was only 22%. Because of advances in medicine and vascular surgery, amputation was far less necessary as a treatment for wounds. No American died from gangrene. Battle fatigue cases were not sent to rear area hospitals, but were treated (psychologically) at regimental clearing stations with hot food, hot showers, and rest. The recovery rate was much higher than a decade before. The most dramatic medical advance was the helicopter, which was experimental in 1950, and in 1951 became a critical device for speedy evacuation to MASH units. The average evacuation time was only five hours. Serious cases required treatment in the States; 43,000 casualties were evacuated by air across the Pacific. 85% of the wounded returned to duty.
The war had reached a stalemate. MacArthur said he could defeat the Chinese by hitting their base camps, airfields and supply dumps in Manchuria, preferably with tactical atomic bombs. The British were aghast--Prime Minister Clement Attlee rushed to Washington and got Truman to promise that no nuclear weapons would be used. MacArthur's repeated requests for permission to return to the roll-back strategy caused a political crisis in Washington. Finally Truman, after securing reluctant consent from the JCS, fired MacArthur on April 11 and replaced him as theater commander with Ridgway. Command of the Eighth Army went to James Van Fleet, a combat veteran from Europe and most recently a key figure in defeating the Communists in the Greek civil war. MacArthur returned home (for the first time since 1937) and took his case to the public. Large majorities blamed Truman for the overall failure in Korea and treated the returning general as a superhero. A "Great Debate" ensued in the halls of Congress, as the Senate heard extended testimony. MacArthur blasted defeatism in Washington, arguing that Communism had to be and could be defeated on the battlefield. The future of Asia was critical to the United States. "There can be no substitute for victory."
Administration spokesmen tried to minimize the damage to Truman by blaming the nation's troubles on MacArthur's oversized ego; they blamed the Chinese intervention on MacArthur's failure to predict it; they insisted that the Korean war was merely a diversion engineered by Stalin to distract Americans from the main arena, Western Europe. Since the status quo ante had been achieved (i.e. South Korea was safe) and containment was a reality, it was time to disengage, said Truman supporters, while holding together the NATO alliance. Fighting China, General Bradley told the country, would be "The wrong war, at the wrong place, at the wrong time, with the wrong enemy." The right war he implied (but did not say) would be fought in Europe against the Soviet Union in a few years.
The debate became a defining moment in the Cold War. The Republican conservatives, lead by Ohio Senator Robert A. Taft, discarded their isolationism and made a 180° turn to support MacArthur and his plans for a rollback of Asiatic Communism. Truman's supporters, on the other hand, abandoned their previous near-unanimous support for rollback (their position as late as November, 1950) and called instead for a policy of containment. The U.S. Department of Defense calculated that reconquest of the north would require eight new Army divisions and the use of tactical nuclear weapons. Holding the line at the 38th parallel, interposing the Seventh Fleet in the Formosa Straits, comprised the containment of both Korea and China. To contain China on the south, the Truman Administration decided to help the French defend Indochina against the Indochinese revolution; support of the French also was a quid pro quo for support in Korea and for NATO in Europe.
In 1952 Truman, after losing the New Hampshire primary, ended his reelection campaign. General Dwight D. Eisenhower defeated the anti-war isolationist Robert A. Taft for the Republican nomination, and electrified the country by promising, "I shall go to Korea," -- that is he would end the war.
The final challenge was to settle the war. With the two armies stalemated along a line that was quite close to the original 38th parallel, peace seemed within reach; formal negotiations opened in July, 1951. Astonishingly, the talks dragged on for two years. The obstacle involved 112,000 North Korean and 20,000 Chinese prisoners of war (POW) held by the UN. On tense occasions at the front lines, American combat soldiers might shoot an enemy trying to surrender. That always happens in warfare; the vast majority of enemy prisoners were well treated. It was UN policy (dictated of course by Truman) that all prisoners should have the option of declining repatriation to their homeland. The goal was to demonstrate the superior appeal of the West, and to avoid a repeat of the horrible fiasco of 1945 when the Allies liberated hundreds of thousands of Soviet POWs held by Germany and forcibly sent back to Stalin, who executed most of them. In 1951 50,000 Communist prisoners held by the Allies rejected repatriation home, a humiliating result China could not accept. The UN policy therefore produced an usually costly stalemate, as 12,000 additional soldiers died in battle and five thousand more languished in POW camps waiting for a solution. (10,200 American had been captured, of whom only 3,700 survived the war). The North Koreans had a cruel policy; they killed prisoners whenever convenient. Most of the surviving Americans were taken by the Chinese, who treated prisoners exactly like their own soldiers--that is, with a severe shortage of food, medicine, clothing, heat, and protection from air raids. The Chinese saw the prisoners as propaganda assets, and attempted to brainwash them into confessions of guilt and recognition of the superiority of Communism. A few were brainwashed, causing a firestorm of criticism regarding the "softness" of American schools.
Eisenhower did go to Korea,and once in office he threatened to use nuclear weapons unless the Chinese came to terms. Eisenhower recalled that he, "Let the Communist authorities understand that, in the absence of satisfactory progress, we intended to move decisively without inhibition in our use of weapons, and would no longer be responsible for confining hostilities to the Korean Peninsula."
His threat may have been a bluff.  An armistice was immediately reached and signed by North Korea, the United States, and China on July 27, 1953, and remains in effect in 2008.
The war-torn landscape of the Korean peninsula, after three years of ground fighting and saturation bombardment by American air power, was in ruins.
For the entire war, 33,400 Americans were killed in battle or died of wounds, (including 2700 who died while a POW); another 3,200 died of accidents or disease. Thus 36,900 Americans were killed, and 103,000 were seriously wounded. The Army suffered 75% of these casualties, the Marines 23%. UN allies suffered about 3,960 killed and 11,500 wounded. The ROK suffered about 257,000 dead, together with 244,000 civilian deaths (half of whom were shot by the KPA forces). Communists still keep their casualties secret, but probably amounted to about a quarter million KPA dead and many wounded, along with several hundred thousand Chinese dead.
- Kathryn Weathersby (Fall 1993), "New Findings on the Korean War", CWIHP Bulletin. Woodrow Wilson International Center for Scholars: 1, 14-18
- William L. O’Neill, American High: The Years of Confidence 1945-1960 (1989), p. 110; David Halberstam, The Fifties (1993), p. 73; Charles C. Alexander, Holding the Line: The Eisenhower Era 1952-1961 (1976), p. 48.
- Cuming vol 1; Andrei Lankov and A. N. Lankov, From Stalin to Kim Il Sung: The Formation of North Korea 1945-1960 (2002)
- Jian Chen, China's Road to the Korean War (1995) Note that China had always considered its borderlands to be part of China, and at the same time were asserting control over Tibet, which had been practically independent for 40 years. Michael Hunt, The Genesis of Chinese Foreign Policy (1996) 16-17; Wanli Hu, "Mao's American Strategy and the Korean War." (2005), ch 1. The older view is expressed in Whiting (1960)
- Shen Zhihua, "Sino-North Korean Conflict and its Resolution During the Korean War." Cold War International History Project Bulletin 2003-2004 (14-15): 9-24. online
- CWIHP #6-7 win 1995/6 p 39
- Cummings 2:447
- Holloway 278
- See telegram from Soviet ambassador Shtykov to Stalin Jul 1, 1950
- Cunningham, “Location of the Aircraft Industry in 1950”, in Simonson, G. R. (ed.), The History of The American Aircraft Industry (1968), p. 206; John S. Day, “Accelerating Aircraft Production in the Korean War”, in Simonson, American Aircraft Industry, p. 223.
- Richard Hallion (1986), The Naval Air War in Korea, Kensington,pp. 58-61
- Hallion, pp. 61-63
- James F. Schnabel. United States Army In The Korean War: Policy And Direction: The First Year (1972) ch 9-10; Korea Institute of Military History, The Korean War (1998) 1:730
- James I. Matray, "Truman's Plan for Victory: National Self-Determination and the Thirty-Eighth Parallel Decision in Korea," The Journal of American History, Vol. 66, No. 2 (1979), pp. 314-333
- Zhou Enlai was told to "concentrate immediately 9 Chinese divisions on the Chinese-Korean border for volunteers' actions in North Korea in the event of the enemy's crossing the 38th parallel. We [USSR] will do our best to provide the air cover for these units." in Stalin to Soviet Ambassador in Beijing, Jul 5, 1950
- Schnable p 212; Robert J. Donovan, Tumultuous Years (1982) p 285.
- When Korea was invaded, the US sent the Seventh Fleet to protect Taiwan from invasion; it is still there. China invaded Tibet in October, 1950. The US informally supported a resistance movement led by the Dalai Lama which made headlines in 2008.
- William Steuck, The Korean War: An International History, (1995) pp 98-103 online excerpt
- see Stalin to Kim Il Sung (via Shtykov), 7 October 1950, online
- Stalin eventually sent in Russian jets and 5000 pilots, disguised in Chinese markings so Moscow could deny their existence. The pilots of course communicated in Russian. CWIHP 6-7:108
- See Ridgway, The Korean War p. 110-1
- Carter Malkasian, "Toward a Better Understanding of Attrition: The Korean and Vietnam Wars," The Journal of Military History, Vol. 68, No. 3 (July 2004), pp. 911-942 in JSTOR
- Robert F. Futrell, The United States Air Force in Korea, 1950-1953 (1961), 482-9, 516-7
- See "Above & Beyond," Time Magazine Aug. 10, 1953
- See Korean War Casualty/Fatality Information
- April 1951 statement by Congressman Albert Gore, Sr. [http://books.google.com/books?id=hfkuktI-JewC&pg=PA437&lpg=PA437&dq=%22a+meat+grinder+of+American+manhood%22&source=web&ots=AClsZotegE&sig=RXMF2REJGc7loRsXXkUvpezProE&hl=en quoted in Barton J. Bernstein, "The Truman Presidency and the Korean War,"] in Lacey, ed. The Truman Presidency (1989) p. 437
- See "Neurosurgery Up Forward," Time Magazine Sep. 10, 1951
- Albert E. Cowdrey, The Medics' War: United States Army in the Korean War (2005)
- Rosemary Foot, "Anglo-American Relations in the Korean Crisis: the British Effort to Avert an Expanded War, December 1950-January 1951." Diplomatic History 1986 10(1): 43-57. ISSN: 0145-2096
- See "The Little Man Who Dared," Time Magazine Apr. 23, 1951
- For excerpts of the debate see "The Argument," Time Magazine Apr. 30, 1951
- "Bradley's Case", Time Magazine, 8 May 1951
- Maxwell D. Taylor (1990), Swords and Plowshares, p. 137
- ""I Shall Go to Korea"", Time, 3 November 1952
- Dwight D. Eisenhower, Mandate for Change: 1953-1965 (1963), p. 180-181, quote at 181. online edition; Michael Gordon Jackson. "Beyond Brinkmanship: Eisenhower, Nuclear War Fighting, and Korea, 1953-1968." Presidential Studies Quarterly. 35#1 . 2005. pp 52+ online version.
- Roger Dingman, "Atomic Diplomacy During the Korean War." International Security 13 (1988-89)
- Allan R. Millett, "Casualties," in Spencer C. Tucker, ed. Encyclopedia of the Korean War (2002) 98-101