As Japanese defensive tactics shifted from the banzai counterattack to increasingly elaborate fortifications, Marine assault tactics were forced to change as well.
While training for the Marianas campaign in the spring of 1944, the Fourth Marine Division emphasized demolitions training for its rifle platoons. One squad from each platoon was given additional training in the use of high explosive, satchel charges, and bunker-busting tactics; flamethrowers and bazookas were carried by company headquarters personnel. On paper, the specially-trained men would be “on call” to deal with trouble spots, but since the men also had to serve as front-line troops, shuffling them around under fire was easier said than done. The dangerous nature of their work meant casualties were high, with few opportunities for replacements.
A new concept grew out of the experience of Saipan and Tinian, reports from Peleliu, and the initial intelligence reports concerning Operation Detachment. On 1 November 1944, volunteers from the division’s line companies reported to their new assignments with their respective assault platoons. Now, each company would have a full squad of specialists on top of their full complement of Marines. The idea was later adopted Corps-wide with the G-series Table or Organization.