With Vought F4U-4S providing air support, the commander in chief of United Nations forces in Korea watches his troops land behind the bulk of the North Korean army, in Douglas MacArthur at Inchon, by Mike Gnatek.
Members of the 5th Marine Regiment climb out of their landing craft and onto the sea wall at Inchon.
General MacArthur conceived of a bold amphibious envelopment through the western coastal port of Inchon in the first days after the North Korean invasion-even while his staff and Washington gloomily confronted the prospect of defeat. From the beginning he visualized a Marine assault force with a follow-on Anny division, and by early July he was requesting the specialized forces required from the Joint Chiefs of Staff (JCS) in Washington. The first hastily drafted Inchon plan. Operation Blueheart, was developed by the ad hoc Joint Strategic Plans and Operations Group (JSPOG) under Colonel Donald Galloway in Tokyo, but it was canceled on July 12 due to deteriorating conditions outside Pusan, MacArthur remained intent on the concept, however, and on August 15 he directed newly arrived Maj. Gen. Clark Ruffner to take charge of JSPOG planning for an invasion to occur in mid-September The date was determined by the prediction of acceptable tides at Inchon.
As forces were identified to take part in the landing, they were hastily trained where possible. The Army’s 7th Infantry Division was given rudimentary amphibious training, while in Japan, the land force headquarters, the instantly created X Corps conducted an intense three-day command post exercise of the invasion and breakout just days before embarking for Korea. Marines assembling from around the world or engaged in combat in Pusan had little or no opportunity for specific training for the new operation.
Marshaling capable forces, particularly amphibious assault elements, was perhaps the most challenging aspect of Chromite. At the time, the entire Marine Corps strength was only 74,279 men on duty around the world, and while there were officially two Marine divisions, it required a herculean effort for the corps to muster even a partial one for Chromite. On July 2, MacArthur asked the JCS for a Marine regimental combat team (RCT). The next day he requested 1,200 landing craft operators, and on the 5th he requested an engineer amphibious special brigade. That same day the 1st Marine Provisional Brigade was formed around the 5th Marine Regiment at Camp Pendleton, Calif., which sailed for Japan on the 14th. During intense negotiations with Washington, MacArthur finally obtained commitments for the two regiments then available from the 1st Marine Division, with the addition of the 1st Marine Regiment and supporting arms. A full division was eventually authorized by stripping Marine security guards from American embassies and a battalion from the Mediterranean, and by calling up the entire Marine Reserves. Despite such efforts, the 1st Division’s third regiment, the 7th Marines, arrived too late for Chromite.
Initially the Army’s 1st Cavalry Division was designated for Blueheart, but after that plan was scrapped the division was rushed into Pusan. The 2nd Infantry Division was later pegged for Chromite before it too was thrown into Pusan. That left only the theater reserve, the 7th Infantry Division in Japan, which itself was denuded of officers, NCOs and specialists to fill out understrength divisions in Korea. After August 1, however, all Army combat replacements arriving from the United States were ordered diverted to the 7th, and these included highly qualified training cadre from the infantry and artillery schools with significant World War II experience. As a measure of the desperate need for manpower in 1950, though, MacArthur ordered on August 1 that the division be filled out with 8,000 untrained Koreans pressed into service from among thousands of refugees crowded into the Pusan Perimeter.
Sealift was another significant hurdle. While the U. S. Navy had large numbers of specialized amphibious vessels left over from World War IT, most were in mothballs, without crews and without the benefit of regular maintenance. To satisfy MacArthur’s requirements the Navy hastily recommissioned ships with scratch crews, including reservists, civilian merchant sailors and even locally recruited Japanese. Of the 47 LSTs (landing ships, tank) that departed Kobe, Japan, on September 10 to support the operation, 37 were manned by Japanese crews. On many of the invasion ships essential equipment and machinery had been stripped out, including radios, electrical systems, pumps, hydraulics and even galleys.
Along with all the other deficiencies facing the Far East Command, no headquarters existed that was capable of commanding the landing force. On August 21, MacArthur requested and received permission to activate the X Corps from among existing assets in the theater. He selected his chief of staff, Maj. Gen. Edward M. Almond, to command the corps and Maj. Gen. Ruffner, from JSPOG, to serve as the corps chief of staff. The X Corps staff was formed out of the Far East Command staff and proved notably competent once on the ground in Korea.
While MacArthur was determined to execute the Inchon operation from early July 1950, he faced considerable opposition and dissension in Washington and from among his own staff and commanders in Tokyo and Korea. The JCS was skeptical about the operation’s viability, partly over the choice of Inchon and the short timetable, but mostly due to the operation’s voracious appetite for scarce resources and forces. During a long late-afternoon meeting at MacArthur’s Tokyo headquarters on July 23, he tentatively prevailed over the concerns of Army Chief of Staff General J. Lawton Collins and Chief of Naval Operations Admiral Forrest Sherman, sent out by the JCS to ascertain the state of affairs. While supporting the concept in principle, they pressed for a landing at Kunsan, much farther south on the west coast.
The next day MacArthur confronted the unanimous objections of his Navy and Marine commanders, who were anxious about the extreme tides at Inchon, mudbanks along the approach, shipping inadequacies, the short timeline to train and prepare, the hazards of conducting an amphibious assault into an urban area and the paucity of personnel to conduct the assault. Once again MacArthur prevailed, partly due to a strong show of support for his subordinates’ needs and concerns. That evening, in a teleconference with Washington, MacArthur gained JCS approval for a two-regiment Marine division, and the 1st Marine Division was alerted to deploy from the American West Coast.
MacArthur’s problems with selling the operation’s viability and obtaining full authorization were far from over, however. On August 6, Averell Harriman arrived in Tokyo as the personal envoy of President Truman, accompanied by Lt. Gen. Matthew Ridgway, the Army deputy chief of staff for operations, and General Lauris Norstad, Air Force vice chief of staff, expressing further doubts from Washington. On August 23, General Collins and Admiral Sherman returned to get yet another update. The next day Sherman met with Navy and Marine commanders to hear their continuing concerns. Lieutenant General Lemuel C. Shepherd Jr., senior Marine in the Far East, then led them into a meeting with MacArthur to appeal for an alternate landing site. When MacArthur would not waiver, his Navy and Marine commanders fully committed themselves to the Inchon landing.
On August 26, MacArthur assigned the name Chromite to the operation, and on the 28th he received JCS approval to proceed-or so he thought. On September 7, the JCS balked again in reaction to further deterioration in the situation around Pusan and the possible necessity to reinforce Walker. They reminded MacArthur that Chromite required all his reserves that it would be another four months before recently activated National Guard divisions could arrive and that the dreaded Korean winter loomed. After a suspenseful night, Truman finally approved the operation on the 8th, and the JCS concurred.
Although it was now approved, MacArthur’s prospects for a smooth execution of the operation remained dim all through the run-up to D-day, set for September 15. A major hurdle was the extraction of the 1st Marine Provisional Brigade from combat in the front lines outside Pusan. The brigade had been diverted directly into Pusan on July 29 after initially setting sail to Japan to prepare for Inchon. Five weeks later the Marines remained in combat, and General Walker adamantly refused to release them for fear of creating a gap in his already weak defenses. Major General Oliver P. Smith, the 1st Marine Division’s commander; had been in Tokyo since August 22, pleading with whomever would listen, including MacArthur and Almond, for the release of his best combat formation. Finally, in a complex arrangement that put a regiment hum the 7th Infantry Division aboard ships in Pusan Harbor as a floating reserve. Walker agreed to its release on September 6. On the 12th the troops finally sailed from Pusan to join their division off Inchon. The 1st Marine Regiment and the rest of 1st Marine Division sailed from Kobe on the 12th, while the 7th Division, minus the regiment floating off Pusan, sailed from Yokohama the same day.
While the invasion fleet muddled its way through the remains of two tropical storms, naval air and gunfire support ships prepared the Inchon landing site on September 13. As a deceptive tactic, the battleship USS Missouri bombarded likely invasion sites along the east coast before joining the main force off Inchon.
The actual landing on September 15 seemed almost anticlimactic. As predicted by intelligence, Inchon proved only lightly defended. According to plan, at 0625 hours the 3rd Battalion, 5th Marines, accompanied by nine M-46 Pershing tanks, assaulted the island of Wolmi-do, a preliminary objective in Inchon Harbor. By 0750, the island had been secured. At that point, in a surreal intermission, the primary assault forces waited in their ships for the necessary high tides.
Finally, at 1645 the landing craft carrying the 1st Marines and the rest of the 5th Marines crossed their lines of departure. At 1733 the 5th Marines assaulted the sea wall by charging up bamboo ladder’s hastily constructed by Japanese workers prior to their embarkation. By midnight, the key high terrain of Cemetery Hill and Observation Hill were in Marine hands. By 0130, all D-day objectives had been met. As dawn broke at 0548 on the 16th, prowling Marine Vought F4U-4 Corsairs jumped six North Korean T-34 tanks on the Seoul highway and destroyed three, for the loss of one Corsair. The remaining T-34s were destroyed later that day by advancing Marine Pershings.
By noon, the 1st Marine Division controlled all high ground east of the city, thus preventing North Korean artillery fire from reaching the beachhead area, and the first 7th Division elements arrived in the harbor. By 1800, the 1st Marine Division tactical headquarters was established ashore and General Smith assumed command of operations from Rear Adm. James H. Doyle, the amphibious group commander. By nightfall, the 5th Marines controlled the Seoul highway.
At first light on the I7th, the 1st Battalion, 5th Marines, engaged and destroyed a further six T-34s. By that evening the 5th Marines had seized the southern portion of Kimpo airfield, a major objective on the outskirts of Seoul. The next day, the third since landing, the 5th Marines secured Kimpo and advanced to the Han River, seizing Hill 99 on the way. That afternoon the first Marine Corsair landed at Kimpo to begin close support operations. By nightfall on the 19th, the 5th Marines had joined with ROK marines for an assault crossing of the Han to begin the attack on Seoul itself.
Back in Inchon, the 2nd Battalion, 32nd Infantry, 7th Division, was ashore and relieved the 2nd Battalion, 1st Marines, along the Seoul highway. The landing and breakout phase was effectively over. Next came the liberation of Seoul and the linkup with the Eighth Army, which had broken out of Pusan and driven pell-mell north up the peninsula. Operation Chromite was over: Mission accomplished.
Two decisive and interrelated factors shaped the operation’s outcome. The first was MacArthur’s faith, persistence and talent in selling the concept, not only to Washington but also to the doubters within his own command. The second was the United States’ ability to quickly marshal appropriate forces in a highly constrained environment. By 1950, a single U. S. Army division defended all of Europe from more than 100 Soviet divisions. The Marine Corps had to scour the world to come up with an ad hoc division for its primary mission, a strategic amphibious assault on a defended shore. The Navy was forced to hastily pull LSTs from mothballs and man them with Japanese crews, while the U. S. Air Force stripped the Air National Guard of World War II veteran North American F-51D Mustang fighters and pilots in order to provide basic close air support.
Underlying those two factor’s in Chromite’s ultimate success was the less glamorous phenomenon of superb staff work behind the scenes at Far East Command, in JSPOG, within the scratch-built X Corps and particularly the dedicated Navy and Marine staffs of Admiral Doyle and General Smith. Finally, as with most successful military endeavors, there was a great deal of luck involved.
For the North Koreans, Inchon was emblematic of the weakness behind its whole scheme to unify Korea. All their hopes of quick success were dashed on the jury-rigged U. N. defense outside Pusan. Inchon sealed their fate. Nonetheless, North Korea had nearly succeeded. It bargained on a lack of will, interest and capability on the part of the United States. Given the signals emanating from Washington, and considering the state of the U. S. military at the time, its analysis was justified. But North Korea underestimated U. S. prospects for mounting so determined a reaction, and it could not have predicted a U. N.-sponsored Allied effort that ultimately involved forces from 16 nations. North Korea gambled and lost.
Operation Chromite did not introduce any fundamentally new aspects to the art of war. Rather, the operation served to reinforce traditional lessons, such as the importance of maintaining trained and ready forces to deter” aggression or confront a contingency, the priceless value of sure-footed staff work, and the tangible benefits of innovation, flexibility and individual resourcefulness- all qualities on which Americans pride themselves.
MacArthur identified a strategic opportunity, managed to cobble together forces to execute a plan and then permitted his commanders and troops to pull it off. The Inchon invasion was undoubtedly the right course of action at that juncture in the fighting and it opened up numerous options for how, when and where to actually end the war. That MacArthur and the administration in Washington subsequently failed to secure the hard-won victory illustrates the danger of military actions out of sync with broader political realities.