How One Marine’s “Forbidden” Brig Trick Made 40 Thieves Stop 3,000-Man Banzai Charge

.
.

In the early hours of September 27, 1942, Lieutenant Colonel William Whailing stood at the edge of Henderson Field on Guadalcanal, his heart heavy with the weight of loss. He watched as four Marines carried a stretcher toward the aid station, a grim reminder of the brutal realities of jungle warfare. At just 22 years old, Whailing had witnessed the devastating toll the Japanese forces were inflicting on his men. That day, a seven-man patrol had been ambushed, leaving only four to return. The jungle, dense and unforgiving, had swallowed them whole.

The Guadalcanal campaign had become a nightmare for the First Marine Division. In just three weeks, 17 patrols had been wiped out, and the enemy moved through the thick vegetation like ghosts. The Japanese had turned the jungle into their weapon, picking off Marines with sniper fire and ambushing squads with hidden machine gun nests. Whailing knew that if they continued with standard infantry tactics, they would be annihilated. The division had already lost 400 men to ambushes in September alone.

Two days earlier, Whailing had been relieved of his command as the executive officer of the Fifth Marine Regiment—not due to combat failure, but because of personality conflicts with his commanding officer. Most officers in his position would have been sent back to the United States, but Colonel Gerald Thomas, the divisional chief of staff, recognized Whailing’s potential. A World War I veteran and expert marksman, Whailing understood fieldcraft better than anyone else in the division. Thomas kept him on Guadalcanal, tasking him with devising a solution to the jungle problem that was costing lives.

Whailing spent three days observing patrols, counting how many returned. The mathematics were brutal, and he realized they needed a different approach. They required men who could hunt the hunters—Marines skilled in stalking, terrain reading, and silent killing. On September 29, Whailing walked into General Alexander Vandergrift’s command tent with a bold proposal: to organize a scout sniper unit composed of 100 handpicked volunteers from the Marine Corps.

Vandergrift, familiar with the tactics of Lieutenant Colonel Robert Rogers from the French and Indian War, saw the potential in Whailing’s plan. He approved it immediately. Whailing had one week to find his men and begin training. That night, he pored over service records, searching for candidates with hunting backgrounds, expert rifle qualifications, and a spirit of independence. By October 1, he had identified 43 potential recruits.

At a briefing on October 2, Whailing made it clear that the assignment was voluntary and warned the men that the casualty rate for reconnaissance work was above 50%. The stakes were high, and he emphasized that they would operate in small teams behind enemy lines with no backup. To his surprise, 41 Marines volunteered immediately, eager to embrace the challenge. Whailing saw the determination in their eyes—these young men, most of whom were under 20, wanted to hunt.

Training began on October 3, 1942. Whailing had no manuals to guide him; the Marine Corps had disbanded its scout sniper program after World War I. Everything he taught came from his extensive experience in the Corps. The first lesson was silence. He took his volunteers into the jungle, instructing them to walk 100 yards without making a sound. Every man failed. The jungle amplified even the slightest noise. Whailing stripped them of noisy equipment, wrapped cloth around canteen hooks, and taught them to walk softly. After three days, half the men could move silently through dense vegetation.

Marksmanship followed. Whailing taught them to estimate distances, judge wind, and account for humidity—all factors that affected bullet trajectory in the jungle. By October 10, his best shooters could kill Japanese soldiers at 400 yards with iron sights. But the hardest part was instilling a sense of independence in these Marines. Unlike regular infantry, they needed to operate in small teams, making tactical decisions without orders. Whailing trained them in map reading, terrain analysis, and ambush tactics—skills that regular infantry never learned.

On October 13, Whailing received orders for an offensive across the Matanakau River. Japanese forces were entrenched on the other side, and regular patrols had been slaughtered trying to locate them. Vandergrift wanted Whailing to take his partially trained unit and scout Japanese positions before the offensive began. Whailing selected eight men, split them into four teams, and sent them out to gather intelligence.

The results were astounding. The teams reported back vital information about Japanese artillery positions and troop movements, information that regular patrols had failed to gather in months. Vandergrift quickly changed his offensive plan, using Whailing’s scout teams to guide flanking maneuvers around Japanese strong points. The concept had proven successful, and now Vandergrift wanted more. He instructed Whailing to expand his unit into a full company.

As the Matanakau offensive began on October 6, 1942, Whailing’s scouts moved out ahead of the main assault. Their mission was to infiltrate Japanese lines, locate command posts, and create chaos before the Marine infantry crossed the river. They moved through the jungle, unseen and unheard, eliminating key targets and disrupting Japanese operations. The fighting lasted four days, with the Marines suffering lighter casualties than in previous offensives.

But Whailing’s success came at a cost. On October 8, he was injured by shrapnel from a mortar round, leading to an infection that would eventually see him evacuated to a hospital ship. He spent the next four months recovering, missing the rest of the Guadalcanal campaign. However, the legacy of his training endured. The First Marine Division formally established scout sniper platoons in each infantry regiment, and Whailing’s methods became official Marine Corps doctrine.

Whailing’s impact on the Marine Corps was profound. He had created a new way of fighting in the jungle, one that emphasized stealth, intelligence gathering, and targeted elimination. His training methods became the foundation for all Marine scout sniper operations through World War II, Korea, and beyond.

In 1944, another Marine officer, First Lieutenant Frank Tachsky, would take Whailing’s ideas and build upon them, creating an elite unit known as the “40 Thieves.” Tachsky sought out the most undisciplined Marines, those who had been incarcerated for fighting, believing that their fierce spirit would serve them well behind enemy lines. He trained them in silent killing and survival skills, preparing them for the brutal combat they would face on Saipan.

As the 40 Thieves embarked on their missions, they became notorious for their audacity and effectiveness. They operated outside the constraints of traditional military tactics, stealing supplies and weapons when necessary to survive. Their actions disrupted Japanese operations and significantly reduced enemy morale.

Ultimately, the 40 Thieves would play a crucial role in the battle for Saipan, executing daring missions that would change the course of the campaign. They faced overwhelming odds and suffered casualties, but their tenacity and skill proved invaluable.

The legacy of William Whailing and the 40 Thieves lives on in the modern Marine Corps. Their stories of courage, ingenuity, and silent determination serve as a reminder that sometimes, the deadliest warriors are those who operate in the shadows, unseen and unheard, yet always ready to strike.