Battle of Pusan Perimeter

Infobox Military Conflict
conflict=Battle of Pusan Perimeter
partof=Korean War


caption=Saddle Ridge near Taegu was defended as part of the Pusan Perimeter
date=August-September 1950
place=Pusan,South Korea
result= U.N. forces victory
combatant1=flagicon|United Nations United Nations:
flag|United States|1912 flag|South Korea
combatant2=flag|North Korea
commander1=
commander2=
strength1=
strength2=
casualties1=
casualties2=|The Battle of Pusan Perimeter was fought in August and September 1950 between United Nations Command forces combined with South Korean forces and the forces of North Korea. The Pusan Perimeter was the area in extreme southeast Korea which was defined by the furthest advance of the North Korean troops during the Korean War. It extended along 140 miles and was named after the coastal city of Pusan. Much of its length coincided with the course of the Nakdong River. The Pusan Perimeter served primarily as an airhead for resupply and reinforcement until the Inchon landing, and counterattack against the North.

Background

After the initial defeats of the Republic of Korea Army (ROK) and United States Army forces at Seoul, Osan and Taejon, the remaining ROK and U.S. forces began consolidating and reorganizing what was left of their units and equipment around the southern port city of Pusan.

The 24th Division shared the defense of South Korea with the rebuilt Republic of Korea Army and two newly arrived U.S. Army divisions, the 25th Infantry Division and the 1st Cavalry Division. On July 24, the ROK Army reorganized itself into two corps and five divisions. The ROK I Corps controlled the 8th Infantry Division and Capital Divisions, while the ROK II Corps controlled the 1st Division and 6th Infantry Division. A reconstituted ROK 3rd Division was placed under direct ROK Army control. The ROK II Corps headquarters was at Hamch’ang with its 1st and 6th Divisions on line from west to east, and the I Corps headquarters was at Sangju with the 8th and Capital Divisions on line from west to east. The 3rd Division operated on the east coast of South Korea. Large numbers of recruits and replacements had entered the ROK Army, which regained its prewar strength of about 95,000.

The U.S. 25th Division, with its three regiments—24th, 27th, and 35th—commanded by Maj. Gen. William B. Kean, arrived between July 10 and July 15, 1950, at Pusan. General Walton Walker ordered the 25th to bolster ROK defenses of the central mountain corridors. The 1st Cavalry Division, with its three regiments—5th, 7th, and 8th—sailed from Japan and landed at P’ohang-dong north of Pusan between July 15 and July 22. The unit assumed responsibility for blocking the North Koreans along the main Taejon-Taegu corridor.

In late July, both the 25th Division and the 1st Cavalry Division withdrew steadily in the face of aggressive North Korean attacks. On July 29, General Walker, with the support of General Douglas MacArthur, issued what the press called a "stand or die" order to the U.S. Eighth Army. Walker emphasized that the retreating must stop. The Eighth Army had been trading space for time, but was running out of space. [ [http://www.trumanlibrary.org/whistlestop/study_collections/korea/large/korea729_82.htm The Korean War: Holding the Line: July 29-August 2, 1950] ]

One of the major problems of the retreat was the volume of refugees moving through Eighth Army lines. Their numbers were greater during July and August 1950 than at any other time in the war. During the middle two weeks of July, about 380,000 refugees crossed into ROK-held territory. The North Koreans often exploited the situation by launching attacks that began by herding groups of refugees across minefields and then following up with tanks and infantry. The North Koreans also infiltrated U.S. Army lines by wearing the traditional white civilian clothing and joining groups of refugees, thus enabling them to mount a variety of surprise attacks on American soldiers. The commanders of the 25th Infantry and 1st Cavalry Divisions attempted unsuccessfully to control the volume of refugees and enemy infiltration by searching displaced civilians and limiting the times and routes available for their movements. In late July, General Walker, with the cooperation of ROK authorities, set explicit rules for the organized removal of refugees to the rear by the ROK National Police. By the end of July, the ROK government had established fifty-eight refugee camps, most of them in the Taegu-Pusan area, to care for the homeless. But even with these efforts, refugees continued to hamper the movement of U.S. and ROK troops.

As the Eighth Army neared a natural defensive position along the Naktong River, the North Koreans accelerated their efforts to cut off elements of that army. After the fall of Seoul in late June, the North Korean 6th Division had crossed the Han River and rapidly moved south over the western coastal roadnet. Eighth Army intelligence lost track of the 6th. The only UN forces situated at the time southwest of the Taejon-Taegu-Pusan highway were a few hundred ROK 7th Division survivors along with some scattered ROK marines and local police. On July 21, General Walker learned that a North Korean unit, presumed to be the North Korean 4th Division, was operating in the southwest area. Walker ordered the 24th Division, despite its deficiencies in manpower and equipment after the loss of Taejon, to serve as a blocking force in the area from Chinju in deep south central Korea northward to Kumch’on. Two battalions of the 29th Infantry, then stationed on Okinawa, and the ROK 17th Regiment would reinforce the 24th Division.

On July 23, the North Korean 4th Division moved south from Taejon with the intent of supporting the 6th Division in an envelopment of the United Nations’ left flank and driving to Pusan. The 4th pushed as far as the Anui-Koch’ang area, about fifty miles (80 km) southwest of Taegu, by the end of July. During July 25–July 28, the two battalions of the 29th were driven back by elements of the 6th at Hadong, located about twenty-five miles (40 km) west of Chinju. On July 31, the Eighth Army finally became aware of the 6th Division’s presence, after the 6th took Chinju and forced one battalion of the 29th and the 19th Infantry of the 24th Division to withdraw to the east. Eighth Army rushed the 27th Infantry of the 25th Division, which had been in reserve, to reinforce American units in the Chinju-Masan corridor. The 24th and 25th Divisions, aided by the ROK 17th Regiment, finally managed to slow the progress of the North Korean 4th and 6th Divisions at what would become the southernmost sector of the Pusan Perimeter. By August 3, U.S. and ROK units had averted the immediate threat of a North Korean drive all the way to Pusan.

Defensive position

On August 1, the Eighth Army issued an operational directive to all UN ground forces in Korea for their planned withdrawal east of the Naktong River. UN units would then establish main defensive positions behind what was to be called the Pusan Perimeter. The intent was to draw the line on retreating and hold off the Korean People's Army while the U.S. Army could build up its forces and launch a counteroffensive. The Pusan Perimeter established by U.S. and ROK forces on August 4 enclosed a rectangular area about 100 miles (160 km) from north to south and 50 miles (80 km) from east to west. The Naktong River formed the western boundary, except for the southernmost 15 miles (24 km) where the Naktong turned eastward after its confluence with the Nam River. The ocean formed the eastern and southern boundaries, while the northern boundary was an irregular line that ran through the mountains from above Waegwan to Yongdok. From the southwest to the northeast, the UN line was held by the U.S. 25th and 24th Infantry and 1st Cavalry Division, and then by the ROK 1st, 6th, 8th, Capital, and 3rd Divisions. From south to northeast, the North Korean units positioned opposite the UN units were the 83rd Motorized Regiment of the 105th Armored Division and then the 6th, 4th, 3rd, 2nd, 15th, 1st, 13th, 8th, 12th, and 5th Divisions and the 766th Independent Infantry Regiment. The 5th Regimental Combat Team from Hawaii and the phased arrival of the 2nd Infantry Division from the United States augmented U.S. Army forces. A third major reinforcement arrived in Korea on August 2, the 1st Provisional Marine Brigade, about 4,700 men. UN combat forces at this point actually outnumbered the North Koreans, 92,000 to 70,000.

Battle

North Korean attack

The North Koreans had four possible avenues of advance leading to Pusan that could result in the defeat of U.S. and ROK forces. In August, they tried them all simultaneously. These approaches went through Masan south of the confluence of the Nam and Naktong Rivers, through the Naktong Bulge to the rail and road lines at Miryang, through Kyongju and down the east coast corridor, and through Taegu. During the first week of August, General Walker decided to launch the first American counterattack of the war in the Chinju-Masan corridor. One of his goals was to break up a suspected massing of enemy troops near the Taegu area by forcing the diversion of some North Korean units southward. On August 6, the Eighth Army issued the operational directive for the attack by Task Force Kean, named for the 25th Division commander. Task Force Kean consisted of the 25th Division, less the 27th Infantry and a field artillery battalion, with the 5th RCT and the 1st Provisional Marine Brigade attached. The plan of attack required the force to move west from positions held near Masan, seize the Chinju Pass, and secure the line as far as the Nam River. Task Force Kean launched its strike on August 7, but ran into a strike being delivered simultaneously by the North Korean 6th Division. After a week of heavy fighting, neither side had made any appreciable progress. Even so, the Eighth Army had launched its first offensive in Korea and successfully halted an assault by an enemy division.

Naktong Bulge

Seven miles (11 km) north of the point where the Naktong River turns east and the Nam River enters it, the Naktong curves westward opposite Yongsan in a wide semicircular loop. This loop became known to the American troops as the Naktong Bulge during the bitter fighting there in August and September. On August 6, the North Korean 4th Division crossed the Naktong at Ohang with the intent of driving to Yongsan located about ten miles (16 km) to the east. The 24th Division defended that sector, and its commander, Major General John H. Church, who had succeeded General Dean, placed the defense of the Naktong Bulge under Task Force Hill. Task Force Hill consisted of the 9th Infantry of the 2nd Infantry Division along with the 34th and 19th Infantries and a battalion of the 21st Infantry of the 24th Division. Despite the efforts of Task Force Hill, by August 11, the 4th Division had penetrated to the vicinity of Yongsan. General Walker then added to the fray the 23rd Infantry of the 2nd Division, the 27th Infantry of the 25th Division, and the 1st Provisional Marine Brigade.

General Church led the coordinated attack of Army and Marine Corps troops on August 17. By August 18, the American forces had decisively defeated the 4th Division, which lost half its original strength of about 7,000 men.

Located about twenty miles (30 km) south of P’ohang-dong on the east coast, Kyongju was an important rail and highway center situated within the Taegu–P’ohang-dong–Pusan triangle inside the Pusan Perimeter. The capture of P’ohang-dong and the nearby Yonil Airfield, used by the Far East Air Force, would open a natural and essentially undefended corridor for the NKPA to move directly south through Kyongju to Pusan. General Walker had only lightly fortified the east coast corridor because of the more immediate enemy threat on the western perimeter, and he doubted that the North Koreans could mount a major successful drive through the trackless mountains. In early August the North Koreans almost proved Walker wrong when three divisions—the 5th, 8th, and 12th—and the 766th Independent Infantry Regiment mounted strong attacks against the ROK defenders. By August 12, the North Koreans had pressed on to P’ohang-dong and also threatened Yonil Airfield. The North Korean 5th Division cut off the ROK 3rd Division above P’ohang-dong, forcing its evacuation by sea to positions farther south. General Walker reinforced the ROK units in the area with elements of the U.S. 2nd Infantry Division. By August 17, ROK units and the 2nd Division had managed to check the enemy drive at P’ohang-dong. A primary factor in stopping the North Koreans was logistics, as they had outrun their supply line during the difficult trek southward through the mountains.

The natural corridor of the Naktong Valley from Sangju to Taegu presented another principal axis of attack for the North Koreans. The sizable forces assembled in an arc around Taegu in early August from south to north consisted of the 10th, 3rd, 15th, 13th, and 1st Divisions and elements of the 105th Armored Division. Opposing the North Koreans were the U.S. 1st Cavalry Division and the 1st and 6th Divisions of the ROK II Corps. The North Koreans crossed the Naktong River in several places within the arc around Taegu during the second week of August. When several enemy artillery shells landed in Taegu on August 18, President Syngman Rhee ordered movement of the Korean provincial government from there to Pusan. The North Korean 1st and 13th Divisions posed the primary threat as they pressed toward Taegu by overland routes from the north and northwest. General Walker moved up the 23rd and 27th Infantries, both fresh from defensive action in the Naktong Bulge, to reinforce the ROK 1st Division, which confronted the North Korean 1st and 3rd Divisions in its sector. Although the North Korean 1st Division pushed to within nine miles (14 km) of Taegu, the combined efforts of the ROK 1st Division and the U.S. 23d and 27th Infantries frustrated enemy efforts to penetrate to Taegu.

Troop reinforcements

Even though the North Korean People’s Army had seriously threatened the United States and ROK Armies within the Pusan Perimeter during August 1950, the defenders successfully resisted the enemy attacks and continued the buildup of forces for a counteroffensive. The Far East Air Force had established air supremacy early in the war and continued to influence the outcome of battles by multiple sorties in close support of ground troops, 4,635 in July and 7,397 in August. By late August, there were more than 500 American medium tanks within the Pusan Perimeter. The tanks in tank battalions were equally divided between M26 Pershings and M4A3 Shermans, except for one battalion that had the newer M46 Pattons. On September 1, the United Nations Command had a strength of 180,000 in Korea: 92,000 were South Koreans and the balance were Americans and the 1,600-man British 27th Infantry Brigade. In August, the North Koreans continued the plan and tactics begun at the Han River in early July with a frontal holding attack, envelopment of the flank, and infiltration to the rear. When the Eighth Army stabilized the line at the Pusan Perimeter, these tactics no longer worked and success could come only by frontal attack, penetration, and immediate exploitation. Generals MacArthur and Walker countered by utilizing their advantages: interior lines of communications, superior artillery firepower, and a strong air force. By September 1, the North Koreans had assembled a 98,000-man army for a massive offensive against the Pusan Perimeter. However, they experienced substantial problems since one-third of their ranks were composed of forcibly conscripted and untrained South Koreans, and they had a major shortage of small arms and only enough rations for one or sometimes two meals per day.

eptember 1950

In early September as during August, General Walker faced dangerous situations in essentially the same places along the Pusan Perimeter: in the east at P’ohang-dong, with the threat of a potential severing of the corridor between Taegu and P’ohang-dong, north of Taegu where the enemy had made disturbing gains, at the Naktong Bulge, and in the Masan area in the extreme south. Also, as he had during the fighting in August, Walker continued his masterful tactics of shifting his forces from one threatened enemy penetration to another. In early September, the ROK 3rd, Capital, 8th, and 6th Divisions held the line farthest to the east against the North Korean 5th, 8th, 12th, and 15th Divisions. Maj. Gen. John B. Coulter, newly appointed deputy commander, Eighth Army, assumed command of American units in the eastern sector and employed the 21st Infantry of the U.S. 24th Division and other supporting units to bolster the ROK divisions. On September 7, General Church replaced Coulter as American commander in the eastern sector after General Walker ordered the entire 24th to reinforce the ROK divisions. A combination of ground fighting, predominantly by the South Koreans, along with American close air support and naval gunfire from offshore inflicted serious losses on the North Korean divisions. The North Korean 1st, 3rd, and 13th Divisions pressed the attack north of Taegu against the U.S. 1st Cavalry Division, which prompted Walker on September 5 to move the main Eighth Army headquarters from Taegu to Pusan. The 1st Cavalry Division essentially checked the thrusts of the North Koreans north of Taegu, but fighting continued there into mid-September.

At the end of August, the North Korean People’s Army also planned a crushing blow against the U.S. 2nd and 25th Divisions in the southern part of the Pusan Perimeter. The North Korean 6th Division would attack through Haman, Masan, and capture Kimhae, fifteen miles (24 km) west of Pusan. The 7th Division was to strike north of the Masan highway, wheel left to the Naktong River, and wait for the 6th Division on its right and the 9th on its left and then resume the attack toward Pusan. The 25th Division held the southernmost sector that ran from the confluence of the Naktong and Nam Rivers to the southern coast, while the 2nd Division was positioned in the area across the Naktong River north of the 25th. The North Korean 9th Division faced the 2nd Division at the Naktong Bulge and had the mission of capturing the towns of Miryang and Samnangjin, thereby cutting off the Eighth Army route of withdrawal between Taegu and Pusan. During the first week of September, the 9th Division penetrated the Naktong Bulge as far east as Yongsan, but a counterattack by the 2nd Division together with the U.S. 1st Provisional Marine Brigade pushed back the 9th almost to the Naktong River. The 2nd Division’s 23d Infantry beat back the North Korean 2nd Division six miles (10 km) north of Yongsan at Changnyong. At the same time, the 6th and 7th Divisions mounted strong attacks against the 25th Division. Despite enemy penetrations into the sectors of the 25th’s regiments—the 35th Infantry’s sector west of Ch’irwon and the 24th Infantry’s sector near Haman that was effectively stopped by the 27th Infantry—the 25th Division repelled the NKPA’s offensive in the south. The Naktong River line held, and the Pusan Perimeter was secure.

Aftermath

Within the space of a few months in 1950, the United States had taken the big leap from attaching no strategic importance to Korea to active involvement there in a major armed conflict. Its army of 591,000 had been focused on the Soviet threat in Western Europe and occupation duty in Europe and the Far East. The four divisions under MacArthur’s Far East Command in Japan were performing primarily occupation duties, and their actual readiness level for conventional combat was even lower than their marginal statistical ratings indicated. Each of MacArthur’s divisions was about 7,000 men short of its authorized strength of 18,900, and none of them had received any new equipment since World War II. MacArthur had not fully supported development of the ROK Army, and in 1948 he had suggested merely expanding the ROK Constabulary. When the ROK minister of defense in 1949 requested M26 Pershing tanks from America, the KMAG argued that the Korean terrain and roads would not allow tank operations, a clearly inaccurate prediction of the Soviet T34 tank’s performance in South Korea during the war’s early stages. When USAFIK withdrew from South Korea in 1949, it did transfer to the ROK Army individual weapons and equipment sufficient for 50,000 men, but these small arms were incapable of repelling enemy armored attacks.

The United States failed to anticipate the North Korean invasion, and KMAG erred in concluding that the ROK Army could withstand an invasion if it happened. Nevertheless, when the attack came, the United States decided to intervene on behalf of South Korea. President Truman authorized air and naval support early in the conflict and the progressive introduction of ground troops. The defeat of Task Force Smith underscored the importance of adequate prewar training along with armored and air support in combat operations.

MacArthur underestimated the skill and determination of the North Koreans but recognized his error when he concluded that more than four U.S. divisions were needed to defeat the enemy. The combined efforts of the U.S. and ROK armies led by General Walker, supplemented by air and naval superiority, slowed the southward drive of the North Koreans and ended in a difficult but successful defense of the Pusan Perimeter. The fighting was intense, as reflected in American casualties to mid-September 1950—4,599 battle deaths, 12,058 wounded, 401 reported captured, and 2,107 reported missing in action. The bitter weeks of retreat and death would soon change, however, with MacArthur’s "hammer against the anvil": the breakout from the Pusan Perimeter coupled with the landing at Inch’on by the 1st Marine Division and the Army’s 7th Infantry Division during the third week of September. [ [http://www.army.mil/cmh-pg/brochures/KW-Outbreak/outbreak.htm Korean War: The Outbreak] ]

Notes

References

*Appleman, Roy E. [http://www.army.mil/cmh-pg/books/korea/20-2-1/toc.htm South to the Naktong, North to the Yalu] United States Army in the Korean War. Washington, D.C.: U.S. Army Center of Military History, 1961.
*Blair, Clay. The Forgotten War: America in Korea. New York: Time Books, 1988.
*Collins, J. Lawton. War in Peacetime: The History and Lessons of Korea. Boston: Houghton Mifflin, 1969.
*Dean, Major General William F. General Dean's Story. New York: Viking Press, 1954.
*Edwards, Paul M. The Pusan Perimeter, Korea, 1950: An Annotated Bibliography. Westport, Conn.: Greenwood Press, 1994.
*Ridgway, Matthew B. The Korean War. Garden City, N.Y.: Doubleday, 1967.
*Schnabel, James F. [http://www.army.mil/cmh-pg/books/P&d.htm Policy and Direction: The First Year] . United States Army in the Korean War. Washington, D.C.: U.S. Army Center of Military History, 1972.

External links

*cite web
url = http://cgsc.leavenworth.army.mil/carl/download/csipubs/robertson/robertson_naktong_part_a.pdf
title = Leavenworth Papers No. 13, Counterattack on the Naktong, 1950
accessdate = 2007-01-10
accessmonthday =
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author =
last = Robertson
first = Dr. William Glenn
authorlink =
coauthors =
date =
year = 1985
month = December
format = PDF
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publisher =
pages = > [http://cgsc.leavenworth.army.mil/carl/download/csipubs/robertson/robertson_naktong_part_a.pdf#page=43 p. 43]
language =
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* [http://www.korean-war.com/TimeLine/1950/08-04to09-15-50.html Evanhoe, E., "Defense of the Pusan Perimeter", 2002, The Korean War web site, accessed Sept. 3, 2006]