[734] PacFlt EvalRpt No. 5, p. 8-5. Subsequently, the division’s ground readiness was rated as excellent; a conservative estimate placed individual unit amphibious readiness at between 25 and 60 percent; and indicated a 30-day training period would bring the division to complete amphibious readiness. Generals’ Summary, p. 53.
Outpost warfare in West Korea was characterized by overextended MLR frontage. The more than 60,000 yards held by the division while in the I Corps sector resulted in a thinly-held line which invited penetration and encirclement. “Normal” frontage for an infantry division in defense with two regiments on line was considered by U.S. Army doctrine to be 8–9,000 yards. Even with four MLR regiments (two Marine, 1st KMC/RCT, and KPR) and the 1st Amphibian Tractor Battalion on line (the third Marine regiment in reserve with a counterattack mission), this was a very lengthy sector. It was further complicated by the Han River obstacle on the left flank and the Imjin River to the rear of the sector that separated Marine frontline troops from rear support and reserve units.
Infantry battalions thus occupied “extremely wide fronts, as a rule 3,500 to 5,000 yards,” while individual rifle companies were assigned anywhere from “1,200 to 1,700 yards of the MLR to occupy and defend.”[735] Prior to the battle of the Hook in October 1952, one of the major engagements on the western front, the 7th Marines at the far right end of the division sector had emplaced all three battalions on line, rather than the customary procedure of two on line and the third in reserve. There was little other choice, for the regimental sector exceeded 10,000 yards, “more properly the frontage for a division rather than a regiment.”[736]
[735] Lessons Learned 5-53, p. 19.
[736] Hicks, Outpost Warfare, p. 107.
During a 100 percent watch, at least theoretically, a Marine could be spaced at intervals about every 10 to 15 yards along the MLR. A night 50 percent watch—with personnel of rifle platoons assigned to COPs, listening posts, combat patrols, repair of fortifications, and the KSC nightly supply trains—not infrequently spread personnel to a point where the MLR was dangerously thin, often with 50 yards between men.[737] Such an over-wide lineal deployment dissipated defensive strength and made mutually supporting fires difficult.
[737] Lessons Learned, op. cit.
Division artillery, too, was thinly positioned across the wide sector, making it difficult to execute counterbattery missions. This led to development of the innovative counter-counterbattery program (or “roving guns”) devised by the 11th Marines in May 1952 to deliberately mislead the CCF as to the strength and location of divisional artillery; the situation resulted as well in the reinforcement of the four Marine artillery battalions by heavier I Corps 155mm and 8-inch howitzers. The static situation in the prolonged land campaign also led to the growth of large, semi-permanent type camps which somewhat hampered traditional Marine mobility. Organizations had additional personnel and equipment above T/O and T/E because of the peculiar defense requirements of the sustained battle situation.
The lack of depth in the defense did not provide for receiving the shock of a determined enemy attack, particularly since the normal OPLR had been withdrawn to strengthen the overextended MLR in April 1952, shortly after the division’s arrival in West Korea. Ultimately, as we have seen, this main line of resistance concept was modified and rather than a long thin trenchline the Marine division employed a defense-in-depth concept using a series of strongpoints, as in Boulder City and the organization of the postwar main battle position. In contrast to the Marine situation (and that of most other divisions in the EUSAK line), the CCF confronting the 1st Marine Division beyond No-Man’s-Land deployed their forces in great depth, boasted unlimited manpower, and employed an elastic type of defense on mutually supporting key terrain features. The enemy had also developed an artillery capability that was numerically superior to ours. And they held high ground positions that overlooked virtually the entire Marine front.
As in World War II, Korean operations provided another instance in which various military services and components were coordinated by joint commands: EUSAK for the ground defense and FAF for air. These massive operational command structures accomplished the desired goals. On lower level echelons, however, some policies tended to be so restrictive that they precluded normal combat initiative and aggressiveness. The net result was thus to allow the enemy to maintain the tactical initiative while, in effect, hampering UNC counter-defense measures.