Another change of lineup took place on 14 July. At this time a battalion from the 15th Regiment, U.S. 3d Infantry Division took over the role of the maneuver element in the Kimpo Provisional Regiment, then held by 1/1, thereby releasing that battalion to its parent unit. With this change, the 1st Marine Division had a full regiment in reserve for the first time since its arrival in western Korea. A later shift in units occurred on 26 July when the 7th and 1st Marines traded places and missions. At that time the MLR, from west to east, was manned by the KPR, 1st AmTrac Bn, KMC, 1st Marines, and 5th Marines.
Opposing them in mid-July were an estimated 27 infantry battalions, whose primary missions were to defend the sectors assigned. The division credited these units with the capability of launching limited objective attacks at any time or of taking part in a major attack with a force of up to 57 infantry and 16 artillery battalions, augmented by 40 tanks or self-propelled guns. It was estimated also that the enemy could cross the Han in battalion strength in the vicinity of the northern shore of Kimpo Peninsula at any time and that Communist aircraft could attack anywhere in the division sector. Enemy forces identified at the end of July, from west to east, were the 193d, 195th, and 194th Divisions of the 65th CCF Army; the 189th Division of the 63d CCF Army; and the 118th Division, 40th CCF Army, which had recently moved from a position opposite the Commonwealth and U.S. 3d Infantry Divisions. Infantry strength of the Communists was established at 28,328.
Replacement and Rotation[146]
[146] Unless otherwise noted, the material in this section is derived from PacFlt EvalRpts No. 4, Chaps. 9, 10; No. 5, Chaps. 8, 9.
Marine infantry strength at the end of July 1952 was little more than half of the Chinese total. The division personnel strength was maintained by the monthly replacement and rotation program of Marines to fill vacancies created by the return of Marine combat personnel to CONUS (Continental United States) and combat losses. In the second quarter of 1952, the division rotated 433 officers and 6,280 enlisted men from Korea. In exchange, 506 officers and 7,359 enlisted men arrived from the States in replacement drafts. A new arrival could expect to stay with the division about 10½ months.
In the late spring of 1952 many of the division’s new replacements were “dental cripples”—Marines requiring dental treatment, even emergency care in some cases.[147] General Selden directed that contact teams be formed to meet the replacement drafts in Japan. During the last leg of the trip to Korea dental personnel screened the new combat Marines on shipboard. By the time the division area had been reached, the dentists knew what remedial work would be required by incoming troops. At the end of the summer the problem was well under control.
[147] Brunelli ltr.
Even though the 1st Marine Division in July continued to be somewhat in excess of its authorized strength in total personnel, it had certain imbalances and was in rather short supply of certain ranks and specialists. While the normal tour for most infantry officers ranged from 9 to 12 months, an excess of company grade officers, particularly lieutenants, had resulted in a reduction of the Korean tour for them to just six months. This brief period of duty plus an intra-division rotation policy that caused a mass shifting of duty assignments every three-to-five months tended to reduce unit combat efficiency. On the other hand the change of assignments had a favorable effect in that it broadened the experience of individual Marines. Beginning in the summer of 1952, however, the division modified this policy to reduce its number of intra-division transfers.
Personnel shortages existed in both the artillery and tank MOSs (Military Occupational Speciality). Mass rotation of reservist company grade artillery officers had necessitated the transfer of infantry officers to the 11th Marines for training and reassignment within the regiment. During the time when the supply of artillery officers was limited, however, the quality of support rendered remained high.[148] The other major shortage in the division was that of qualified crewmen—both drivers and gunners—for the M-46 tanks. Neither tank driving nor gunnery for the M-46 was taught in the tank crewmen’s course conducted at Camp Pendleton, California. General Selden requested of Lieutenant General Franklin A. Hart (CG, FMFPac) that “tank crewmen be thoroughly trained prior to leaving the U.S.”[149]
[148] PacFlt EvalRpt No. 4, p. 9-27.