In the predawn hours of Sunday, June 25, 1950, the North Korean forces, spearheaded by tanks and self-propelled guns, unleashed all-out attacks across the 38th parallel. The Korean War consisted of four distinct phases. Initially, the Communist army advanced against increasing resistance as it forced the United Nations defenders into the Pusan perimeter in the most southeastern part of South Korea.
The second phase began in 1950 when the North Koreans suffered a complete reversal of fortune when the UN forces landed at Inchon, far beyond the battle line; burst from the Pusan perimeter; shattered the North Korean Army; and pursued its remnants northward.
The third phase began when China intervened in force in November 1950, surprising the scattered United Nations armies as they approached North Korea’s northern border and driving them back to the vicinity of the 38th parallel.
Finally, the fourth phase was a stalemate, during which neither side would risk vast casualties in an attempt to gain a complete victory.
Truce talks began in July 1951, but the fighting continued until July 1953, when the negotiations at last bore fruit and the conflict ended in a cease-fire agreement.
Unlike after its previous wars, the United States did not fully and immediately demobilize after the fighting subsided in Korea. Production and spending continued at a relatively high level. In this respect, the Korean War was the most important event in the history of the Cold War, and, indeed, was a watershed in American military history. After this war, the United States embarked on the first long-term peacetime program of military and industrial preparedness. No longer would the country virtually disarm after a war; instead, it would promote the concept of readiness. No longer was the question whether or not to produce, but what to produce and how much.
In comparison to the naval forces engaged in World War II, Korea was a small war. At no time were more than four large carriers in action at the same time. Yet in the 3 years of war, Navy and Marine aircraft flew 276,000 combat sorties, dropped 177,000 tons of bombs and expended 272,000 rockets. This was within 7,000 sorties of their World War II totals in all theaters and bettered the bomb tonnage by 74,000 tons, and the number of rockets by 60,000.
The Korean Conflict was chaotic and difficult for American Artillery. Classical front lines disappeared. Artillery units often found themselves surrounded and artillerymen were called upon to fight side by side with the infantry. Artillery was used to perform rear guard actions. To make up for their lack of artillery, the Chinese made American battery positions their prime targets. Batteries had to fight off invaders in close combat and still fire their guns in support of the combat operations.
Three air interdiction operations, two named STRANGLE and another called SATURATE, tried to paralyze the enemy’s transportation system upon which he relied for supplies. Weather and an inability to execute sustained night attacks thwarted these efforts. Much more successful was the campaign to employ air power to pressure the Chinese into accepting an Armistice satisfactory to the United States. This “air pressure” campaign was perhaps a key factor in finally ending the war. Attacks, in June 1952, on four hydroelectric generating complexes at Suiho, Chosin, Fusen, and Kyosen opened the campaign. These raids were spectacularly successful; North Korea experienced a nearly total loss of electric power for two weeks and never regained its former level of generating capacity before the end of the war. Manchuria, too, suffered the loss of a quarter of its supply of electricity. By the end of 1952, jet fighters had largely replaced the vulnerable F-51s for air-to-ground support. Even the older F-80 jet fighters sometimes proved too vulnerable.
The war left indelible marks on the Korean Peninsula and the world surrounding it. The entire peninsula was reduced to rubble, and casualties on both sides were enormous [though as with most wars, subject to conflicting claims]. Combatant deaths alone included as many as 180,000 South Korean and United Nations troops. In June 2000 the US Department of Defense revised the the number of Americans killed in the conflict, from 54,246 to 36,940, to include 33,000 actual battlefield deaths. The higher figure — widely cited for nearly half a century — mistakenly included all 20,617 non-battlefield US military deaths that had occurred worldwide during the three-year conflict. Only to the more than dead in Korea. But only 3,275 non-battlefield deaths, due to accident or disease, occurred in Korea. Estimates of the number of Communist soldiers killed range as high as 1,420,000 — 520,000 North Koreans and 900,000 Chinese — though these claims were surely inflated. Chinese sources report that only 110,000 Chinese soldiers were killed in action with another 35,000 dying of wounds and disease.