he’d been assigned his military occupational specialty, or MOS: 0301, infantry officer, inexperienced. If he was still alive in six months he would be anointed 0302, infantry officer, experienced. All Marine infantry specialties were designated by zero-three followed by different pairs of numbers: 0311, rifleman; 0331, machine gunner. Zero-three, called “oh-three,” was dreaded by many Marines because it meant certain combat.
