Logistics in the Battle of Pusan Perimeter (August 4 – September 15, 1950) during the Korean War played a decisive role in the battle. Efficient logistics, the management of personnel and materiel, supported United Nations (UN) supply lines while the North Koreans' routes of supply were steadily reduced and cut off. UN logistics improved throughout the Battle of Inchon and the defeat of the North Korean army at Pusan.
UN forces, consisting mostly of troops from the Republic of Korea (ROK), the United States (US), and United Kingdom (UK), enjoyed overwhelming air and sea superiority during the battle. The UN efficiently procured and transported supplies from a large stockpile of materiel in nearby Japan.
In contrast, North Korean logistics were hampered by UN interdiction campaigns which slowed the flow of supplies from North Korea to the battle. Though supported logistically by the Soviet Union and China during the battle, North Koreans often had difficulties getting their supplies from depots to the front lines, leaving North Korean troops unsupported during several crucial engagements.
Background
Outbreak of war
On the night of June 25, 1950, ten divisions of North Korea's Korean People's Army (KPA) launched a full-scale invasion on the nation's neighbor to the south, the Republic of Korea. The force of 89,000 men moved in six columns, catching the Republic of Korea Army by surprise, resulting in a complete rout. The smaller South Korean army suffered from widespread lack of organization and equipment, and it was unprepared for war. Numerically superior, North Korean forces destroyed isolated resistance from the 38,000 South Korean soldiers on the front before it began moving steadily south. Most of South Korea's forces retreated in the face of the invasion. By June 28, the North Koreans had captured South Korea's capital of Seoul, forcing the government and its shattered army to retreat further south.
To prevent South Korea's complete collapse, the United Nations Security Council voted to send military forces. The United States' Seventh Fleet dispatched Task Force 77, led by the fleet carrier USS Valley Forge; the British Far East Fleet also dispatched several ships, including HMS Triumph, to provide air and naval support. Although the navies blockaded North Korea and launched aircraft to delay the North Korean forces, these efforts alone did not stop the North Korean Army juggernaut on its southern advance. To supplement the air support, US President Harry S. Truman ordered ground troops into the country. Although the Eighth United States Army's US 24th Infantry Division was in Japan and was available to respond to the situation, cuts in military spending after the end of World War II meant that the overall strength of the US military in the Far East was limited and the division itself was understrength and operating outmoded equipment. Nevertheless, the division was ordered into Korea.
The 24th Infantry Division was the first US unit sent into Korea with the mission to take the initial "shock" of North Korean advances alongside the South Korean army, delaying much larger North Korean units to buy time to allow UN reinforcements to arrive. The division was consequently alone for several weeks as it attempted to delay the North Koreans while the 7th Infantry Division, 25th Infantry Division, 1st Cavalry Division, and other Eighth Army supporting units moved into position. On July 5, during the first battle between American and North Korean forces, advance elements of the 24th Infantry Division were badly defeated at Osan. Over the course of the following month, the 24th Infantry Division was repeatedly defeated and forced south by the stronger and more heavily equipped North Koreans. During this time heavy fighting occurred around Chochiwon, Chonan, and Pyongtaek before the 24th Infantry Division made a final stand at Taejon. Although they were almost completely destroyed in the fighting, the US troops were able to delay North Korean advance until July 20, by which time the Pusan Perimeter had been established. With UN units arriving every day, the Eighth Army was able to build up a force of combat troops that were roughly equal to North Korean forces attacking the region.