Post-assault Operations in the Palaus
When on 20 October Major General Mueller became responsible for mopping up on Peleliu, he addressed the tactical problem as a siege situation, and directed his troops to proceed accordingly. Over a period of nearly six weeks, his two regiments, the 322d and 323d Infantry, plus 2/321, did just that. They used sandbags as an assault device, carrying sand up from the beaches and inching the filled sandbags forward to press ever nearer to positions from which to attack by fire the Japanese caves and dug-in strong points. They made liberal use of tanks and flamethrowers, even improving upon the vehicle-mounted flamethrower. They thrust a gasoline pipeline forward from a roadbound gasoline truck, thereby enabling them, with booster pumps, to throw napalm hundreds of feet ahead into Japanese defensive areas. Noting the effectiveness of the 75mm pack howitzer which the Marines had wrestled up to Hill 140, they sought and found other sites to which they moved pack howitzers, and from which they fired point-blank into defending caves. To support their growing need for sandbags on ridge-top “foxholes,” their engineers strung highlines to transport sand (and ammo and rations) up to such peaks and ridgetops.
Department of Defense Photo (USMC) 98401
As a result of Maj Gayle’s targetting of enemy positions in the Umurbrogol, napalm-laden Marine Corsairs lifted from Peleliu’s airfield, and returned to the field to be rearmed, in perhaps the shortest wheels-down bombing run of the Pacific War.
Notwithstanding these deliberate siege tactics, the 81st troops still faced death and maiming as they ground down the bitter and stubborn Japanese defenses. The siege of the Umurbrogol Pocket consumed the full efforts of 81st Division’s 322d RCT and 323d RCT, as well as 2/321, until 27 November 1944 (D plus 73).
This prolonged siege operation was carried on within 25 miles of a much larger force of some 25,000 Japanese soldiers in the northern Palaus. Minor infiltrations aside, those Japanese were isolated by U.S. Navy patrols, and by regular bombing from Marine Aircraft Group 11, operating from Peleliu.
Difficult and costly as the American advances were, the Japanese defenders in their underground positions had a similarly demanding and even more discouraging situation. Water was low. Sanitation was crude to nonexistent. Rations were short, and ammunition was even scarcer. As time wore on, some of the Japanese, when afforded opportunity, chose to leave their defenses and undertake futile, usually suicidal night attacks. A very few succeeded in being captured.
Toward late November, even Major General Murai apparently came to this point of view. Still not in command, he nevertheless proposed, in a radio message to Lieutenant General Inoue on Koror, a banzai finale for their prolonged defense. But General Inoue turned down the proposal. By this time, Nakagawa’s only exterior communications were by radio to Koror. As he had anticipated, all local wire communications had been destroyed. He had issued mission orders to carry his units through the final phase of defense.
As the tanks and infantry carefully pressed their relentless advances, the 81st Division’s engineers pressed forward and improved the roads and ramps leading into or toward the heart of the Japanese final position. This facilitated the tank and flamethrower attacks to systematically reduce each cave and position as the infantry pushed its sandbag “foxholes” forward.