Battle of Inchon

The Battle of Inchon (인천 상륙 작전, Incheon Sangnyuk Jakjeon) was an amphibious invasion and battle of the Korean War that resulted in a decisive victory and strategic reversal in favor of the United Nations. The operation involved some 75,000 troops and 261 naval vessels, and led to the recapture of the South Korea capital Seoul two weeks later. The code name for the operation was Operation Chromite.

The battle began on 15 September 1950 and ended on 19 September. Through a surprise amphibious assault far from the Pusan Perimeter that UN and South Korean forces were desperately defending, the largely undefended city of Incheon was secured after being bombed by UN forces. The battle ended a string of victories by the invading North Korean People's Army (NKPA). The subsequent UN recapture of Seoul partially severed NKPA's supply lines in South Korea.

The majority of United Nations ground forces involved were U.S. Marines, commanded by General of the Army Douglas MacArthur of the United States Army. MacArthur was the driving force behind the operation, overcoming the strong misgivings of more cautious generals to a risky assault over extremely unfavorable terrain.

Pusan Perimeter
From the outbreak of the Korean War following the invasion of South Korea by North Korea on 25 June 1950, the North Korean Korean People's Army had enjoyed superiority in both manpower and equipment over South Korea's Republic of Korea Army and the United Nations forces dispatched to South Korea to prevent it from collapsing. The North Korean strategy was to aggressively pursue U.N. and South Korean 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 North Koreans to surround and cut off the opposing force, forcing it to retreat in disarray, often leaving behind much of its equipment. From their initial 25 June offensive to fights in July and early August, the North Koreans used this strategy to defeat any UN force they encountered and push it south. However, with the establishment of the Pusan Perimeter in August, the U.N. troops held a continuous line which the North Koreans could not flank, and their advantages in numbers decreased daily as the superior U.N. logistical system brought in more troops and supplies to the U.N. forces.

When the North Koreans approached the Pusan Perimeter on 5 August, they attempted the same frontal assault technique on the four main avenues of approach into the perimeter. Throughout August, their military conducted direct assaults resulting in the Battle of Masan, the Battle of Battle Mountain, 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 South Koreans repulsed three North Korean divisions at the Battle of P'ohang-dong. The North Korean attacks stalled as U.N. forces, well equipped and with large standing reserve units to draw upon, repeatedly repelled them. All along the front, the North Korean troops reeled from these defeats, the first time in the war North Korean strategy had failed.

By the end of August the North Korean troops had been pushed beyond their limits and many of the original units were at far reduced strength and effectiveness. Logistic problems racked the North Korean army, and shortages of food, weapons, equipment, and replacement soldiers proved devastating for North Korean units. However, the North Korean force retained high morale and enough supply to allow for another large-scale offensive. On 1 September the North Koreans 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 U.N. forces by surprise and almost overwhelmed them. North Korean 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 North Koreans were unsuccessful. Unable to hold their gains, the North Korean army retreated from the offensive a much weaker force, and vulnerable to counterattack.

Planning
Days after the beginning of the war, General of the Army Douglas MacArthur, the U.S. Army officer in command of all U.N. 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 North Korean army would push the Republic of Korea Army back far past Seoul. He also said he decided days after the war began that the battered, demoralized, and under-equipped South Koreans, many of whom did not support the South Korean government put in power by the United States, could not hold off the North Korean forces even with American support. MacArthur felt that he could turn the tide if he made a decisive troop movement behind enemy 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 U.S. Army's 1st Cavalry Division landing at Inchon. 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, Operation Chromite, calling for an amphibious assault by the U.S. Army's 2nd Infantry Division and the United States Marine Corps's 5th Marine Regiment in mid-September 1950, but this, too fell through as both units were moved to the Pusan Perimeter as well. MacArthur decided instead to use the U.S. 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 U.S. 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 U.S. Marine Corps, 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 U.S. 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, South Korean Army conscripts assigned to U.S. 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 U.S. Army's Eighth Army on the front lines.



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 – three to eight knots (3.5 to 9.2 mph; 5.5 to 14.8 km/hr). Finally, 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." U.S. Navy leaders favored a landing at Kunsan, but MacArthur overruled these because he did not think they would be decisive enough for victory. He also felt that the North Koreans, 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 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 U.S. Navy Admiral James H. Doyle spoke for nearly 90 minutes on every technical and military aspect of the landing. MacArthur told the officers that though a Kunsan landing would bring a relatively easy linkup with the Eighth Army, a landing there "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 U.S. 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.



Despite these obstacles, in September MacArthur issued a revised plan of assault on Incheon: Plan 100-B, codenamed Operation Chromite. MacArthur spent 45 minutes after the briefing explaining his reasons for choosing Incheon. He said that because it was so heavily defended, the enemy would not expect an attack there, that victory at Incheon would avoid a brutal winter campaign, and that, by invading a northern strong point, U.N. forces could cut off North Korean lines of supply and communication. He also chose Incheon because of its proximity to Seoul. Admiral Sherman and General Collins returned to Washington, D.C., and had the invasion approved.

The landing at Incheon was not the first large-scale amphibious operation since World War II. That distinction belonged to the 18 July 1950 U.N. landing at Pohang, South Korea. However, that operation was not made in enemy-held territory and was unopposed.

Prelude
Before the main land battle, U.N. forces landed spies in Incheon and bombarded the city's defenses via air and sea. U.N. forces also conducted deception operations to draw enemy attention away from Incheon.

Maintaining surprise
With men, supplies, and ships obviously concentrating at Pusan and in Japanese ports for a major amphibious operation and the press in Japan referring to the upcoming landings as "Operation Common Knowledge," the U.N. command feared that it would fail to achieve surprise in the Incheon landings. Exacerbating this fear, the leader of a North Korean-Japanese spy ring arrested in Japan in early September 1950 had a copy of the plan for Operation Chromite, and the U.N. forces did not know if he had managed to transmit the plan to North Korea before his arrest. U.S. Navy patrol aircraft, surface warships, and submarines operated in the Sea of Japan and the Yellow Sea to detect any reaction by North Korean, Soviet, or People's Republic of China military forces, and on 4 September 1950 United States Navy F4U Corsair fighters of Fighter Squadron 53 (VF-53) aboard the aircraft carrier USS Valley Forge (CV-45) shot down a Soviet Air Force A-20 Havoc bomber after it opened fire on them over the Yellow Sea as it flew toward the U.N. naval task force there.

In order to ensure surprise during the landings, U.N. forces staged an elaborate deception operation to draw enemy attention away from Incheon by making it appear that the landing would take place 105 miles (169 km) to the south at Kunsan. On 5 September 1950, aircraft of the United States Air Force's Far East Air Forces began attacks on roads and bridges to isolate Kunsan, typical of the kind of raids expected prior to an invasion there. A naval bombardment of Kunsan followed on 6 September, and on 11 September U.S. Air Force B-29 Superfortress bombers joined the aerial campaign, bombing military installations in the area.

In addition to aerial and naval bombardment, U.N. forces took other measures to focus enemy attention on Kunsan. On the docks at Pusan, United States Marine Corps officers briefed their men on an upcoming landing at Kunsan within earshot of many Koreans, and on the night of 12-13 September 1950 the Royal Navy frigate HMS Whitesand Bay (F633) landed United States Army special operations troops and Royal Marine Commandos on the docks at Kunsan, making sure that enemy forces noticed their visit.

U.N. forces conducted a series of drills, tests, and raids elsewhere on the coast of Korea, where conditions were similar to Inchon, before the actual invasion. These drills were used to perfect the timing and performance of the landing craft, but also were intended to confuse the North Koreans further as to the location of the invasion.

Incheon infiltration
Fourteen days before the main attack on Incheon, a joint Central Intelligence Agency–military intelligence reconnaissance effort, codenamed Trudy Jackson, placed a team in Incheon Harbor. The group, led by U.S. Navy Lieutenant Eugene F. Clark, landed at Yonghung-do, an island in the mouth of the harbor. From there, they relayed intelligence back to U.N. forces.

With the help of locals, Lieutenant Clark, Republic of Korea Navy Lieutenant Youn Joung, and former South Korean counterintelligence officer Colonel Ke In-Ju gathered information about tides, beach composition, mudflats, and seawalls. The tides at Incheon have an average range of 29 feet (8.8 meters) and a maximum observed range of 36 feet (11 meters), making the tidal range there one of the largest in the world and the littoral maximum in all of Asia. They observed the tides at Inchon for two weeks and discovered that American tidal charts were inaccurate, but, fortunately, Japanese charts were quite good. They provided detailed reports on North Korean artillery positions and fortifications on the island of Wolmido, at Incheon, and on nearby islands. During the extensive periods of low tide they located and removed some enemy naval mines, but, critically to the future success of the invasion, Clark reported that the North Koreans had not in fact systematically mined the channels.

When the North Koreans discovered that the agents had landed on the islands near Inchon, they made multiple attacks, including an attempted raid on Yonghung-do with six junks. Clark mounted a machine gun on a sampan and sank the attacking junks. In response, the North Koreans killed perhaps as many as 50 civilians for helping Clark.

Bombardments of Wolmido and Incheon


On 10 September 1950, five days before the Inchon landing, 43 American warplanes flew over Wolmido, dropping 93 napalm canisters to “burn out” its eastern slope in an attempt to clear the way for American troops.

The flotilla of ships that landed and supported the amphibious force during the battle was commanded by U.S. Navy Vice Admiral Arthur D. Struble, an expert in amphibious warfare. Struble had participated in amphibious operations in World War II, including the Normandy landings and the Battle of Leyte. He got underway for Incheon in his flagship, the heavy cruiser USS Rochester (CA-124), on 12 September 1950.

As the landing groups neared, cruisers and destroyers from the United States and Canada shelled the fortifications on Wolmido and checked for mines in Flying Fish Channel. The first Canadian forces entered the Korean War when the Royal Canadian Navy destroyers HMCS Cayuga, HMCS Athabaskan, and HMCS Sioux bombarded the coast. The U.N. Fast Carrier Force offshore flew fighter cover, interdiction, and ground attack missions. Hundreds of Korean civilians were killed in these attacks on the lightly defended port.

At 07:00 on 13 September, the U.S. Navy's Destroyer Squadron Nine, headed by the destroyer USS Mansfield (DD-728), steamed up Eastern Channel and into Incheon Harbor, where it fired upon North Korean gun emplacements on Wolmido. The attacks tipped off the North Koreans that a landing might be imminent, and the North Korean officer in command on Wolmido assured his superiors that he would throw the enemy back into the sea.

North Korean artillery returned fire, inflicting significant damage on three of the attacking warships, killing one U.S. Navy sailor and wounding six others. The destroyer USS Collett (DD-730) received the most damage; she took nine 75-millimeter-shell hits, which wounded five men. The destroyer USS Gurke (DD-783) sustained three shell hits resulting in light damage and no casualties. The one dead man, David H. Swenson from the destroyer USS Lyman K. Swenson (DD-729), was later reported by the world media as being the nephew of Captain Lyman Knute Swenson, USS Lyman K. Swenson's namesake, but this was later found to be false.

Between them, the Canadian and American destroyers fired over a thousand 5-inch (127-mm) shells, inflicting severe damage on Wolmido's fortifications.

The American destroyers withdrew after bombarding Wolmido for an hour and Rochester, the U.S. Navy heavy cruiser USS Toledo (CA-133), and the British Royal Navy light cruisers HMS Jamaica (C44) and HMS Kenya (14) proceeded to bombard the North Korean batteries for the next three hours from the south of the island. Lieutenant Clark and his South Korean squad watched from hills south of Incheon, plotting locations where North Korean machine guns were firing at the U.S. ships. They relayed thus information to the invasion force via Japan in the afternoon.

During the night of 13-14 September, Vice Admiral Struble decided on another day of bombardment, and the destroyers moved back up the channel off Wolmido on 14 September. They and the cruisers bombarded the island again that day, and planes from the carrier task force bombed and strafed it.

At 00:50 on 15 September 1950, Lieutenant Clark and his South Korean squad activated the lighthouse on the island of Palmido. Later that morning, the ships carrying the amphibious force followed the destroyers toward Incheon and entered Flying Fish Channel, and Marines of the invasion force got ready to make the first landings on Wolmido.

Green Beach
At 06:30 on September 15, 1950, the lead elements of X Corps hit "Green Beach" on the northern side of Wolmido. The landing force consisted of the 3rd Battalion, 5th Marine Regiment, led by Lieutenant Colonel Robert Taplett and nine M26 Pershing tanks from the U.S. Marine Corps' 1st Tank Battalion. One tank was equipped with a flamethrower and two others had bulldozer blades. The battle group landed from tank landing ships (LSTs). The entire island was captured by noon at the cost of just 14 casualties.

The North Korean forces were outnumbered by more than six to one by the U.N. troops. North Korean casualties included over 200 killed and 136 captured, primarily from the 918th Artillery Regiment and the 226th Independent Marine Regiment. The forces on Green Beach had to wait until 19:50 for the tide to rise, allowing another group to land. During this time, extensive shelling and bombing, along with anti-tank mines placed on the only bridge, kept the small North Korean force from launching a significant counterattack. The second wave came ashore at "Red Beach" and "Blue Beach".

The North Korean army had not been expecting an invasion at Incheon. After the storming of Green Beach, the NKPA assumed (probably because of deliberate American disinformation) that the main invasion would happen at Gunsan. As a result, only a small force was diverted to Incheon. Even those forces were too late, and they arrived after the UN forces had taken Blue Beach and Red Beach. The troops already stationed at Incheon had been weakened by Clark's guerrillas, and napalm bombing runs had destroyed key ammunition dumps. In total, 261 ships took part.

For Red Beach and Blue Beach, Vice Admiral James H. Doyle, Commander of an Amphibious ready group, announced that H-Hour, time of landing, would be 17:30.

The North Korean 22nd Infantry Regiment had moved to Inch’on before dawn on September 15, 1950, but retreated to Seoul after the main landing that evening.

Red Beach


The Red Beach forces, made up of the Regimental Combat Team 5, which included the 3rd Battalion of the Republic of Korea Marine Corps (ROKMC), used ladders to scale the sea walls. Then-Lieutenant Colonel Raymond L. Murray's, served as Commanding Officer of the 5th Marines, mission was to seize an area three thousand yards long and a thousand yards deep, extending from Cemetery Hill (northern) at the top down to the Inner Tidal Basin (near Tidal Basin at the bottom) and including the promontory in the middle called Observatory Hill. (See Map) The 1st Battalion would be on the left, against Cemetery Hill and northern half of Observatory Hill. The 2nd Battalion would take the southern half of Observatory Hill and Inner Basin.

Late on the afternoon of September 15, the LSTs closed Red Beach and as the lead ships they came under heavy mortar and machine gun fire from North Korean defenders on Cemetery Hill. Despite the concentrated fire, they disembarked assault troops and unloaded vital support equipment. In addition their guns wiped out enemy batteries on the right flank of Red Beach. Three (LST 857, LST 859 and LST 973 ) of the eight LSTs took some hits from mortar and machine gun fire, which killed a sailor and injured a few others. The LSTs completed unloading and cleared the beach at high tide early on 16 September.

After neutralizing North Korean defenses at Inchon on the night of September 15, they opened the causeway to Wolmi-do, allowing the 3rd Battalion of the 5th Marines and the tanks from Green Beach to enter the battle at Inchon. Early morning on September 16, the 5th Marines (Red and Green Beaches forces) would march through the city in Inchon, taking it by the afternoon.

Red Beach forces suffered eight dead and 28 wounded.

Blue Beach
Under the command of then-Colonel Lewis Burwell "Chesty" Puller, the 1st Marine Regiment landing at Blue Beach was significantly south of the other two beaches and reached shore last. The mission of Colonel Puller's 1st Marines in this landing was to take the beachhead, and the road to Yongdungpo and Seoul. The 2nd Battalion would land on the left at Blue Beach One and 3rd Battalion would land on Blue Beach Two. A little cove around the corner south of Blue Beach Two was called Blue Beach Three. As they approached the coast, the combined fire from several NKPA gun emplacements sank one LST. Destroyer fire and bombing runs silenced the North Korean defenses. When they finally arrived, the North Korean forces at Incheon had already surrendered, so the Blue Beach forces suffered few casualties and met little opposition. The 1st Marine Regiment spent much of its time strengthening the beachhead and preparing for the inland invasion.

Air attack on USS Rochester
Just before daylight at 0550 on 17 September, a North Korean Yak-9 and an II-2 made an attack run on Rochester while she was anchored off Wolmi-do. Initially the aircraft were thought to be friendly until they dropped four bombs over the American ship. All but one missed and the one that did hit dented Rochester's crane and failed to detonate. There were no American casualties in the skirmish and they painted a Purple Heart on the crane as a reminder of how close the ship had come to being heavily damaged. After the bombing of Rochester, she and the nearby Jamaica opened fire on the attacking aircraft with their guns. The North Korean II-2 then strafed the British cruiser, resulting in one sailor killed and two wounded. At about the same time, fire from Jamaica hit the II-2 and it crashed into the water. The Yak-9 fled after losing its partner.

Beachhead


Immediately after North Korean resistance was extinguished in Incheon, the supply and reinforcement process began. Seabees and Underwater Demolition Teams (UDTs) that had arrived with the U.S. Marines constructed a pontoon dock on Green Beach and cleared debris from the water. The dock was then used to unload the remainder of the LSTs.

Documents written by Kim Il-sung and recovered by UN troops soon after the landing said, "The original plan was to end the war in a month, we could not stamp out four American divisions...We were taken by surprise when United Nations troops and the American Air Force and Navy moved in."

Early that morning of September 16, Lieutenant Colonel Murray and Colonel Puller had their operational orders from General Oliver P. Smith. The 1st Marines and 5th Marines began moving along the Inchon-Seoul road.

On September 16, the North Koreans, realizing their blunder, sent six columns of T-34 tanks to the beachhead. They were quite alone, without infantry support. They were spotted by a strike force of F4U Corsair at the village of Kansong-ni, east of Inchon. In response, two flights of F4U Corsair from Marine Fighter Squadron 214 (VMF-214) bombed the attackers. The armored columns suffered extensive damage and the U.S. forces lost one airplane. A quick counter-attack by M26 Pershing tanks destroyed the remainder of the North Korean armored division and cleared the way for the capture of Incheon.

Capture of Kimpo airfield
The Kimpo airfield was the largest and most important in Korea.

On September 17, General MacArthur was extremely urgent in his request for early capture of Kimpo airfield for it was the largest air base in all of Korea. Once it was secured, the Fifth Air Force could bring fighters and bombers up from Japan to operate more easily against North Korea. The attack on Kimpo airfield was carried out by 2nd Battalion 5th Marines. That night at Kimpo, the North Koreans were organizing their defense of the airfield. Kimpo was under the command of Brigadier General Wan Yong. General Wan's troops were a conglomeration of half-trained fighting men and service forces. Several North Korean troops had already fled across the Han River toward Seoul to escape the fight. The North Korean's defense was almost as bad as the morale of the men who realized that they were not going to get any help from the North Korean officials in Seoul.

By morning the enemy were all gone, and Kimpo airfield was securely in the hands of the Marines. Kimpo airfield was in excellent shape; the enemy had not had time to do any major demolition. In fact, several enemy planes were still on the field. So Kimpo now could become the center of Allied land-based air operations.

On September 19, the U.S. Army Corps of Engineers repaired the local railroad up to eight miles (13 km) inland. After captured of Kimpo airfield, transport planes began flying in gasoline and ordnance for the aircraft stationed there. The Marines continued unloading supplies and reinforcements. By September 22, they had unloaded 6,629 vehicles and 53,882 troops, along with 25,512 tons (23,000 tonnes) of supplies.

Battle of Seoul


In contrast to the quick victory at Incheon, the advance on Seoul was slow and bloody. The NKPA launched another T-34 attack, which was trapped and destroyed, and a Yak bombing run in Incheon harbor, which did little damage. The NKPA attempted to stall the UN offensive to allow time to reinforce Seoul and withdraw troops from the south. Though warned that the process of taking Seoul would allow remaining NKPA forces in the south to escape, MacArthur felt that he was bound to honor promises given to the South Korean government to retake the capital as soon as possible.

On the second day, vessels carrying the U.S. Army's 7th Infantry Division arrived in Incheon Harbor. General Almond was eager to get the division into position to block a possible enemy movement from the south of Seoul. On the morning of September 18, the division's 2nd Battalion of the 32nd Infantry Regiment landed at Incheon and the remainder of the regiment went ashore later in the day. The next morning, the 2nd Battalion moved up to relieve an U.S. Marine battalion occupying positions on the right flank south of Seoul. Meanwhile, the 7th Division's 31st Regiment came ashore at Incheon. Responsibility for the zone south of Seoul highway passed to 7th Division at 18:00 on September 19. The 7th Infantry Division then engaged in heavy fighting with North Korean soldiers on the outskirts of Seoul.

Before the battle, North Korea had just one understrength division in the city, with the majority of its forces south of the capital. MacArthur personally oversaw the 1st Marine Regiment as it fought through North Korean positions on the road to Seoul. Control of Operation Chromite was then given to Major General Edward Almond, the X Corps commander. General Almond was in an enormous hurry to capture Seoul by September 25, exactly three months of the North Korean assault across the 38th parallel. On September 22, the Marines entered Seoul to find it fortified. Casualties mounted as the forces engaged in house-to-house fighting. On September 26, the Hotel Bando (which had served as the US Embassy) was cleared by Easy Company of 2nd Battalion, 1st Marine Regiment. During this fight about 12 North Korean P.O.W.s were killed (apparently while naked and unarmed) in the building's basement.

General Almond declared the city liberated on September 25 even though Marines were still engaged in house-to-house combat.

Pusan Perimeter breakout
Meanwhile, 5th Marines came ashore at Inchon. The last North Korean troops in South Korea still fighting were defeated when Walton H. Walker's 8th Army broke out of the Pusan Perimeter, joining the Army's X Corps in a coordinated attack on NKPA forces. Of the 70,000 NKPA troops around Pusan, in the aftermath of the Pusan Perimeter battle, North Korean casualties from September 1 to September 15 could range from roughly 36,000 to 41,000 killed and captured, with an unknown total number of wounded. However, because UN forces had concentrated on taking Seoul rather than cutting off the NKPA's withdrawal north, the remaining 30,000 North Korean soldiers escaped to the north across the Yalu River, where they were soon reconstituted as a cadre for the formation of new NKPA divisions hastily re-equipped by the Soviet Union. The allied assault continued north to the Yalu River until the intervention of the People's Republic of China in the war in November 1950.

Analysis
Most military scholars consider the battle one of the most decisive military operations in modern warfare. However, Russell Stolfi argues that the landing itself was a strategic masterpiece but it was followed by an advance to Seoul in ground battle so slow and measured that it constituted an operational disaster, largely negating the successful landing. He contrasts the US style of war fighting with that of Germany by examining the US military's 1950 Incheon-Seoul operation and the German offensive in the Baltic in 1941. American forces achieved a strategic masterpiece in the Incheon landing in September 1950 and then largely negated it by a slow, tentative, 11-day advance on Seoul, only twenty miles away. By contrast in the Baltic region in 1941 the German forces achieved strategic surprise in the first day of their offensive and then, exhibiting a breakthrough mentality, pushed forward rapidly, seizing key positions and advancing almost two hundred miles in four days. The American advance was characterized by cautious, restrictive orders, concerns about phase lines, limited reconnaissance, and command posts well in the rear, while the Germans positioned their leaders as far forward as possible, relied on oral or short written orders, reorganized combat groups to meet immediate circumstances, and engaged in vigorous reconnaissance.