Pusan Perimeter From the outbreak of the Korean War following the invasion of South Korea by North Korea on 25 June 1950, the KPA had enjoyed superiority in both manpower and ground combat equipment over the ROK and UN forces dispatched to South Korea to prevent it from collapsing. The North Korean strategy was to aggressively pursue UN and ROK forces on all avenues of approach south and to engage them,
attacking from the front and initiating a
double envelopment of both flanks of the defending units, which allowed the KPA to surround and cut off the opposing force, forcing it to retreat in disarray. From their initial 25 June offensive to fighting in July and early August, the KPA used this tactic to defeat the UN forces they encountered and push southward. the
First Battle of Naktong Bulge, the
Battle of Taegu, and the
Battle of the Bowling Alley. On the east coast of the
Korean Peninsula, the ROK repulsed three KPA divisions at the
Battle of P'ohang-dong. The KPA attacks stalled as UN forces repelled the attack. All along the front, the KPA reeled from these defeats, the first time in the war North Korean tactics had failed. By the end of August the KPA had been pushed beyond their limits and many of the original units were at far reduced strength and effectiveness. Logistic problems wracked the KPA, and shortages of food, weapons, equipment and replacement soldiers proved devastating for their units. However, the KPA retained high morale and enough supply to allow for another large-scale offensive. On 1 September the KPA threw their entire military into one final bid to break the Pusan Perimeter, the
Great Naktong Offensive, a five-pronged simultaneous attack across the entire perimeter. The attack caught UN forces by surprise and almost overwhelmed them. KPA troops
attacked Kyongju,
surrounded Taegu and
Ka-san, recrossed the
Naktong Bulge, threatened
Yongsan, and continued their attack at Masan, focusing on
Nam River and
Haman. However, despite their efforts, in one of the most brutal fights of the Korean War, the KPA were unsuccessful. Unable to hold their gains, the KPA retreated from the offensive a much weaker force, and vulnerable to counterattack.
Planning Douglas MacArthur (center) grasps
General J. Lawton Collins (the
Army Chief of Staff, left) and
Admiral Forrest Sherman (the
Chief of Naval Operations, right) upon their arrival in
Tokyo, Japan. MacArthur used their meeting to convince other military leaders that the assault on Incheon was necessary. Days after the beginning of the war,
General of the Army Douglas MacArthur, the US Army officer in command of all UN forces in Korea, envisioned an
amphibious assault to retake the
Seoul area. The city had fallen in the first days of the war in the
First Battle of Seoul. MacArthur later wrote that he thought the KPA would push the ROK back far past Seoul. He also said he decided days after the war began that the battered, demoralized, and under-equipped ROK, many of whom did not support the South Korean government put in power by the United States, could not hold off the KPA even with American support. MacArthur felt that he could turn the tide if he made a decisive troop movement behind KPA lines, and preferred
Incheon, over
Chumunjin-up or
Kunsan as the landing site. He had originally envisioned such a landing, code-named
Operation Bluehearts, for 22 July, with the US Army's
1st Cavalry Division landing at Incheon. However, by 10 July the plan was abandoned as it was clear the 1st Cavalry Division would be needed on the Pusan Perimeter. On 23 July, MacArthur formulated a new plan, code-named Operation Chromite, calling for an amphibious assault by the US Army's
2nd Infantry Division and the
United States Marine Corps (USMC)'s
5th Marine Regiment in mid-September 1950. This, too fell through as both units were moved to the Pusan Perimeter. MacArthur decided instead to use the US Army's
7th Infantry Division, his last reserve unit in
East Asia, to conduct the operation as soon as it could be raised to wartime strength. In preparation for the invasion, MacArthur activated the US Army's
X Corps to act as the command for the landing forces, and appointed
Major General Edward Almond, his
chief of staff, as Corps' commander, anticipating the operation would mean a quick end to the war. Throughout August, MacArthur faced the challenge of re-equipping the 7th Infantry Division as it had sent 9,000 of its men to reinforce the Pusan Perimeter and was far understrength. He also faced the challenge that the USMC, reduced in size following
World War II, had to rebuild the
1st Marine Division, using elements of the
1st Provisional Marine Brigade fighting at Pusan as well as the
1st Marine Regiment and the
7th Marine Regiment, which pulled US Marines from as far away as the
Mediterranean Sea to Korea for the task. MacArthur ordered
Korean Augmentation To the United States Army (KATUSA) troops, ROK conscripts assigned to US Army units, to reinforce the 7th Infantry Division, while allocating all equipment coming into Korea to X Corps, despite it being crucially needed by the US Army's
Eighth Army on the Pusan Perimeter. of
Fighter Squadron 113 (VF-113) (the "Stingers") flies over UN ships off Incheon, Korea, on 15 September 1950. VF-113 was assigned to Carrier Air Group Eleven (CVG-11) aboard the
aircraft carrier . The
battleship is visible below the Corsair. MacArthur decided to use the
Joint Strategic and Operations Group (JSPOG) of his
United States Far East Command (FECOM). The initial plan was met with skepticism by the other generals because Incheon's natural and artificial defenses were formidable. The approaches to Incheon were two restricted passages, which could be easily blocked by
naval mines. The current of the channels was also dangerously quick——and tides were so extreme as to prevent immediate follow-on landings. The anchorage was small and the harbor was surrounded by tall
seawalls.
United States Navy Commander Arlie G. Capps noted that the harbor had "every natural and geographic handicap." US Navy leaders favored a landing at Kunsan, closer to the Pusan perimeter and the KPA main axis of supply through
Taejon, but MacArthur did not think landing there would produce a sufficiently decisive victory. He also felt that the KPA, who also thought the conditions of the Incheon channel would make a landing impossible, would be surprised and caught off-guard by the attack. On 23 August, the commanders held a meeting at MacArthur's headquarters in Tokyo.
Chief of Staff of the United States Army General Joseph Lawton Collins,
Chief of Naval Operations Admiral Forrest Sherman, and
United States Air Force (USAF) operations deputy
Lieutenant General Idwal H. Edward all flew from
Washington, D.C., to
Japan to take part in the briefing;
Chief of Staff of the United States Air Force General
Hoyt Vandenberg did not attend, possibly because he "did not want to legitimize an operation that essentially belong[ed] to the Navy and the Marines." The Marine Corps staff, who were to be responsible for leading the landing at Incheon, were not invited, which became a contentious issue. During the briefing, nine members of the staff of US Navy Admiral
James H. Doyle spoke for nearly 90 minutes on every technical and military aspect of the landing. MacArthur told the officers that although a landing at Kunsan would bring a relatively easy linkup with the Eighth Army, it "would be an attempted
envelopment that would not envelop" and would place more troops in a vulnerable pocket of the Pusan Perimeter. MacArthur won over Sherman by speaking of his affection for the US Navy and relating the story of how the Navy carried him out of
Corregidor to safety in 1942 during World War II. Sherman agreed to support the Incheon operation, leaving Doyle furious. MacArthur spent 45 minutes after the briefing explaining his reasons for choosing Incheon. He said that, because it was so heavily defended, the North Koreans would not expect an attack there, that victory at Incheon would avoid a brutal winter campaign, and that, by invading a northern strong point, UN forces could cut off KPA lines of supply and communication. Sherman and Collins returned to Washington, D.C., and reported back to Secretary of Defense
Louis A. Johnson. The Joint Chiefs of Staff approved MacArthur's plan on 28 August. President Truman also provided his approval. The landing at Incheon was not the first large-scale amphibious operation since World War II. That distinction belonged to the United Nations landing that took place on 18 July 1950 at
Pohang, South Korea. However, that operation was not made in KPA-held territory and was unopposed. Admiral
Arthur Dewey Struble's Joint Task Force 7 consisted of
Fast Carrier Task Force 77 for fighter cover, interdiction, and ground attack;
Royal Navy Admiral
William Andrewes'
Task Force 91 for blockade and covering force; Rear Admiral
George R. Henderson's Task Force 99 for patrol and reconnaissance; Captain
Bernard L. Austin's Service Squadron 3, operating Task Force 79 for logistics support; Admiral
James H. Doyle's Invasion Force -
Attack Task Force 90; and the
Military Sea Transportation Service, which was to bring in the
United States Army's
7th Infantry Division on 18 September 1950. ==Prelude==