Advance, Retreat, and Stalemate: A Limited War in the Nuclear Age

By Scott R. Gourley - May 25, 2014

Infantrymen of the 27th Infantry Regiment near Heartbreak Ridge take advantage of cover and concealment in tunnel positions, 40 yards from the communists, on Aug. 10, 1952. U.S. Army photo

“By its participation in the Korean conflict the Army of the United States, in a determined effort to restore international peace and security, has been for the first time committed to battle under the flag of the United Nations. Confronted by most arduous conditions, the American soldier has fought with traditional bravery and skill against communist aggression in Korea. He has met every test with honor.”

– Gen. J. Lawton Collins, U.S. Army Chief of Staff, Aug. 16, 1949-Aug. 15, 1953

“The men who make history have no time to write about it.”

– Prince Klemens von Metternich (1773-1859)

Fortunately, 19th century Austrian statesman Metternich was to be proven wrong in the century following his death. In fact, Collins’ praise for the American soldier cited above appears as an introduction to a two-volume historical examination that was prepared and published by the Department of the Army in the period during and immediately following the Korean conflict. Unlike some subsequent conflict histories that were compiled long after the fact, the two Department of the Army volumes, republished by the Army’s Center of Military History in 1988-1989, provide modern readers with an accurate and time-appropriate framework for examining the subject of both Army and Marine Corps ground operations during the Korean War.

For most historical purposes, the start of the U.S. ground war experience in Korea is generally marked from President Harry S Truman’s June 29, 1950, authorization for Gen. Douglas MacArthur to commit ground troops to blunt communist aggression from the north. Korean War ground actions went on to span three years, one month, and two days, “officially” ending with the signing of the armistice on July 27, 1953.

United Nations troops fighting in the streets of Seoul, Korea, Sept. 20, 1950. Korean War Signal Corps Photograph Collection

The two government volumes identify 13 distinct phases to the Korean War ground operations during this period. The initial volume identifies four primary phases of ground war operations during 1950: Withdrawal to the Pusan Perimeter (June 25-July 31); Defense of the Pusan Perimeter (Aug. 1-Sept. 14); U.N. Counteroffensive (Sept. 15-Nov. 24); and Withdrawal from the Yalu (Nov. 25-Dec. 31). The second volume of the series goes on to identify nine more phases to the ground conflict: Enemy High Tide (Jan. 1-24, 1951); Attack and Counterattack (Jan. 25-Feb. 28, 1951); Crossing the 38th Parallel (March 1-April 21, 1951); Enemy Strikes Back (April 22-May 19, 1951); U.N. Resumes Advance (May 20-June 24, 1951); Lull and Flare-up (June 25-Nov. 12, 1951); Stalemate (Nov. 12, 1951-June 30, 1952); Outpost Battles (July 1-Dec. 31, 1952); and The Last Battle (Jan. 1-July 27, 1953).

Drawing primarily on the Department of the Army history, this article offers a broad overview of the units committed and types of operations conducted during each general phase of ground operations on the Korean peninsula.

At the time of the initial invasion, U.S. ground force strength was comprised of 10 U.S. Army divisions and a U.S. Marine Corps division, with a large percentage of this capability still “under strength” from the post-World War II demobilization process. Moreover, it was a full five days after the U.S. government received official notification of the North Korean invasion south across the 38th parallel that Truman authorized MacArthur to commit U.S. ground forces in Korea.

At the time of the initial invasion, U.S. ground force strength was comprised of 10 U.S. Army divisions and a U.S. Marine Corps division, with a large percentage of this capability still “under strength” from the post-World War II demobilization process. Moreover, it was a full five days after the U.S. government received official notification of the North Korean invasion south across the 38th parallel that Truman authorized MacArthur to commit U.S. ground forces in Korea. The South Korean capital had already fallen to the communists the day prior, leaving behind a rapidly eroding political and military climate for the introduction of troop units. As a result, the opening stages of the ground war in Korea involved the commitment of U.S. troop units into a combat action that was already withdrawing south down the Korean peninsula toward what would come to be called the Pusan Perimeter – to signify its enclosure of the United Nations (U.N.) supply port at Pusan.

The rapidly disintegrating battlefield situation prompted a decision by MacArthur to begin the commitment of U.S. ground elements in a “piecemeal” fashion, beginning with one-half of a battalion combat team from the 21st Infantry Regiment of the U.S. 24th Division. Known as Task Force Smith, the unit was transported to Korea by air during July 1-2, and immediately charged north by rail and truck to face incredible odds against the North Korean military onslaught. Meeting an entire division of North Korean armor and infantry on July 5, the partial battalion of U.S. infantry held its ground for seven hours before withdrawing back through other elements from the 24th Division that had followed the task force to Korea.

A bazooka team of the 24th Infantry Division goes into action North Korean tanks at the village of Sojong-Ni, near Osan. The M9 2.36-inch bazooka proved ineffective against North Korean T-34s. At right is Pfc. Kenneth Shadrick, who was mortally wounded by enemy machine-gun fire a few moments after this photo was taken, becoming the first U.S. soldier to die in the Korean campaign. U.S. Army photo

The initial plan tasked the 24th Division with fighting a delaying action while additional reinforcements were shipped from Japan and, eventually, the United States.

Next to arrive was the 25th Division, which began crossing from Japan on July 9, and the 1st Cavalry Division (Infantry), which disembarked from its ship convoy nine days later. They were joined about a week later by the separate 29th Regimental Combat Team (RCT). By the end of the month, all of these units were concentrated in a foothold protecting Taegu and Pusan at the southeastern corner of the peninsula.

The four-day action was characterized by point-blank artillery missions and extensive North Korean infiltration of U.N. lines, but by Aug. 11, the task force had secured the left flank of the Eighth Army and forced North Korean withdrawal from many of their now tenuous salients.

The subsequent six-week defense of that foothold marked the second major phase of the ground war in Korea. The period included the arrival of three more large contingents of U.S. reinforcements: the 2nd Division from the United States; the 5th RCT from Hawaii; and the 1st Provisional Marine Brigade (advance component of the 1st Marine Division) from the United States. To assist in the reinforcement of depleted U.S. forces, August also saw the initial integration of South Korean nationals into U.S. Army company-sized units.

Representative of the combat activities during this period were the actions of Task Force Kean, consisting of elements of the 25th Division, the 1st Provisional Marine Brigade, and a Republic of Korea (ROK) battalion. The task force was thrown against the North Korean 6th Division, which had been massing in the mountains on the left flank of the perimeter prior to an assault on Pusan. The U.N. counteroffensive opened on Aug. 7, and was supported by Marine, Navy, and Air Force aircraft. The four-day action was characterized by point-blank artillery missions and extensive North Korean infiltration of U.N. lines, but by Aug. 11, the task force had secured the left flank of the Eighth Army and forced North Korean withdrawal from many of their now tenuous salients.

U.S. Marines guarding three captured North Koreans, 1950. National Archives photo

Similar combat actions took place at other locations along the front, all featuring stories of amazing heroism on the part of U.N. ground forces. The situation was far from a stalemate, as evidenced by places like Sobuk Ridge (“Battle Mountain”) that changed ownership more than a dozen times in less than a month.

One feature of Korean War land operations that jumps from the pages of the history compiled at the time was the frequent and painful infiltration of U.S./U.N. lines by “enemy soldiers in civilian clothes,” an aspect of communist warfare that was clearly a new experience for most U.S. personnel.

One feature of Korean War land operations that jumps from the pages of the history compiled at the time was the frequent and painful infiltration of U.S./U.N. lines by “enemy soldiers in civilian clothes,” an aspect of communist warfare that was clearly a new experience for most U.S. personnel.

Nonetheless, the actions undertaken by the United States and a growing array of allied forces in defense of the Pusan “beachhead” clearly demonstrated the ability of U.N. forces to counterattack, an opportunity that was exploited on a grand scale in mid-September when the recently activated U.S. X Corps (comprised of the 1st Marine Division and 7th Infantry Division) made a surprise amphibious landing at Inchon. The Sept. 15 landing provided the opportunity for the Eighth Army to attack out of their beachhead perimeter. The Eighth Army was now composed of two ROK corps and two U.S. corps, the latter units featuring participation by the 27th British Commonwealth Brigade and additional attached ROK units.

The perimeter was steadily expanded against often fierce resistance. By Sept. 26, however, a unit of the 1st Cavalry’s 70th Tank Battalion had raced ahead through enemy positions to join forward elements of the 7th Division that had fought southeast from Inchon. Meanwhile, the capital, Seoul, was officially returned to friendly hands the same day. A continuing retreat by communist forces led to the crossing of the 38th parallel by initial ROK elements on Oct. 1, with U.S. and Commonwealth troops quickly moving over to bring the war to North Korean soil.

Marine Pfc. Luther Leguire raises a U.S. flag at the American consulate in Seoul on Sept. 27, 1950, while fighting for the city raged around the compound. U.S. Marine Corps photo

After capturing Seoul and Suwon, X Corps had been withdrawn from combat to prepare for a second amphibious landing on the east coast, again behind enemy lines, at the North Korean port of Wonsan. However, the rapidity of the North Korean retreat translated to an Oct. 26 administrative landing by the 1st Marine Division at Wonsan and an Oct. 29 landing by the U.S. 7th Division, with ROK supplement, 178 miles north at Iwon.

U.N. forces prepared for a final push, with the Eighth Army operating west of the mountains and the X Corps to the east.

While the U.S. IX Corps and ROK III Corps stayed in South Korea to destroy pockets of bypassed resistance, the U.S. X Corps and Eighth Army (now supplemented by a Turkish Brigade) continued their drives in the north. By the fourth week of October, elements of the U.S. 7th Division were looking across the Yalu River into Manchuria in China. U.N. forces prepared for a final push, with the Eighth Army operating west of the mountains and the X Corps to the east.