CDG 66 – Marines at Pusan Perimeter, Korea, 1950
The January 2015 issue of Armchair General® presented the Combat Decision Game “Marines at Pusan Perimeter, Korea, 1950.” This CDG placed readers in the role of U.S. Marine Corps Captain Ike Fenton, commander of B Company, 1st Battalion, 5th Marine Regiment, 1st Marine Provisional Brigade, during the early months of the Korean War. Fenton’s mission on August 17, 1950, was to lead an attack to seize and hold key terrain on Obong-Ni Ridge that was being occupied by North Korean forces.
Almost two months earlier, on June 25, 1950, 230,000 North Korean People’s Army (NKPA) troops, led by a brigade of Soviet-built T-34 tanks, launched an invasion across the 38th parallel that divides communist North Korea from democratic South Korea (Republic of Korea, or ROK). The 65,000-man ROK army proved no match for the NKPA invaders, and even the commitment of U.S. ground troops in July disastrously failed to stop the enemy advance.
By the beginning of August, the North Korean offensive had pushed General Walton Walker’s U.S. 8th Army, consisting of ROK and U.S. forces, into a 90-by-60-mile enclave near Pusan at the southeastern tip of the Korean peninsula. Holding the “Pusan perimeter” was vital, as this would give General of the Army Douglas MacArthur the time he needed to mobilize, train and equip the forces necessary to mount a devastating counterstroke to defeat the NKPA invasion and save South Korea.
By mid-August, however, Walker’s hard-pressed troops were barely maintaining a tenuous hold on the Pusan perimeter defensive line. Moreover, further enemy attacks had forced a dangerous “bulge” in the perimeter’s southwestern sector by seizing a bridgehead across the Naktong River. From there, the NKPA forces were in position to strike east toward the vital port of Pusan, whose capture would have collapsed Walker’s entire defense.
Fenton’s attack was a crucial operation to stop the NKPA forces from expanding the Naktong bridgehead, thereby preventing them from seizing Pusan and collapsing the Pusan perimeter defense.
Fenton decided that to give his company the best chance for success, he needed to concentrate his attack on the northern tip of the enemy-held Obong-Ni Ridge and then roll up the NKPA defenses one by one from north to south (COURSE OF ACTION ONE: RIGHT HOOK). Hitting the enemy from the flank also had the advantage of keeping Fenton’s attacking Marines well out of the line of fire from the company’s supporting mortar, artillery and machine guns, allowing these weapons to freely blast NKPA positions along the ridge without fear of hitting friendly troops. Moreover, the flank attack restricted the enemy’s ability to bring all of its defending troops and supporting firepower to bear against the Marines.
As rounds from mortars, artillery and machine guns hit NKPA positions all along the ridge, B Company’s 1st Platoon led the attack, closely followed by 2d Platoon. After the assault began to bog down at the first objective, Hill 102, Fenton committed 3d Platoon as reinforcement. This provided the combat power needed to take the hill, and soon afterward the second objective, Hill 109, was captured. But once the Marines had seized the ridge, they still had to hold it.
Throughout the night of August 17-18, 1950, masses of NKPA troops counterattacked to regain the key terrain. Fenton’s Marines held the ridge, but they paid a stiff price. On August 17, B Company had gone into the line with five officers and 190 men; 24 hours later, Fenton was the only officer left and just 88 of the company’s Marines remained combat effective (and many of those were “walking wounded” who refused medical evacuation).
Shortly after the fight for Obong-Ni Ridge, famed photojournalist David Douglas Duncan visited Fenton’s company, which was still holding the Naktong River line against repeated NKPA attacks. Duncan took a haunting photograph of the physically exhausted and emotionally drained Captain Fenton that was published in the September 18, 1950, issue of Life magazine. The image is one of the most starkly compelling statements ever made about the toll that combat takes on those who must endure its ravages. (Good Read: 100 Greatest Military Photographs by Robert J. Dalessandro, Erin R. Mahan and Jerry D. Morelock; Whitman Publishing, 2013.)
ACG judges based their selections for winning Reader Solutions and those receiving honorable mention on submissions that chose COURSE OF ACTION ONE: RIGHT HOOK, or those whose explanations demonstrated a solid understanding of the key principles for a “seize and hold” attack. (See “After Action Report.”) This plan concentrated B Company’s attacking forces against the most vulnerable sector of the enemy line, since the NKPA defenders were unable to bring to bear all their men and supporting firepower against the company’s assault. Moreover, this plan allowed the Marines to mass against the two principal objectives (Hill 102 and Hill 109) one at a time, thereby increasing the company’s chances of overwhelming each position’s defenders. Finally, this course of action made the best use of Fenton’s supporting firepower, which could fire freely at the entire ridge without fear of hitting friendly troops.
Since COURSE OF ACTION TWO: TWO PLATOONS ABREAST supporting mortars, artillery and machine guns to fire over the heads of B Company’s advancing troops, it put the company at risk of incurring friendly-fire casualties and inhibited full use of supporting fire as the Marines closed on their objectives. Moreover, simultaneously attacking both objectives prevented the Marines from massing overwhelming numbers against either one, thereby increasing the risk that the attack would fail to capture one, or perhaps both, of the key ridge-top positions.
COURSE OF ACTION THREE: THREE PLATOONS ABREAST not only had essentially the same disadvantages as COA Two, but it also placed the entire company at risk of incurring heavy casualties by exposing all of B Company to the enemy’s full firepower as Fenton’s Marines advanced over open terrain. Therefore, even if this plan had succeeded and the Marines had seized the ridge, B Company potentially could have suffered such heavy casualties that it would have been too weak to hold the ridge against subsequent NKPA counterattacks.
After Action Report
Key Points for a “Seize and Hold” Attack
- SURPRISE the enemy with the location and timing of the attack.
- CONCENTRATE combat power against enemy weaknesses.
- ENSURE all supporting weapons have clear fields of fire.
- REORGANIZE the unit for defense as soon as the objective is seized.
- RESUPPLY ammunition, food and water immediately.
- EVACUATE the wounded expeditiously, without disrupting defensive preparations.
- REINFORCE threatened sectors with timely commitment of reserves.