Marmon-Herrington CTLS: America's Forgotten Tankette (Not a Tank)

January 4, 2021 Topic: History Region: Americas Blog Brand: The Reboot Tags: TanksTanketteAmericaU.S. ArmyWorld War II

Marmon-Herrington CTLS: America's Forgotten Tankette (Not a Tank)

The Marine Corps was the first and last branch to use light tanks.

Here's What You Need to Know: In the event of a conflict with China, the Marine Corps might once again need a lighter, more amphibious tank.

American armor is perhaps best known for the M1 Abrams, one of the biggest, heaviest main battle tanks in existence. The iconic M4 Sherman of World War II renown also enjoys a great deal of attention. Perhaps less well-known however is the Marmon-Herrington CTLS.

Combat Tank Light Series

The CTLS was originally designed for service with the United States Marine Corps in the late 1930s, right before the outbreak of World War II. The USMC wanted to field a lightly armored amphibious tank that could take part in landing operations and be used to augment landing party’s firepower once on the beach.

To that end, the Marmon-Harrington company designed the CTLS. Their tank lacked a turret, and its armor was only about a half inch thick. But what it lacked in armor protection it made up for in sheer firepower. It had not one, but three machine guns—two M1919 .30 caliber machine guns and one M2 Browning heavy machine gun.

It was far from perfect. In an effort to make the tankette as light as possible, armor protection was sacrificed to the point of being very poorly protected. The CTLS’ tracks also lacked the robustness needed for maneuvering on austere island battlefield environments. The USMC would eventually reject the design for general service.

They did see service in Alaska however, during one of World War II’s more obscure campaigns. For about a year’s time, spanning across 1942 and 1943, Japanese forces successfully invaded and held two Alaskan islands in the Aleutian Island chain. As a stop-gap measure, the CTLS was issued to U.S. Army forces and used to dislodge the Japanese invaders from American soil.

The CTLS was also briefly saw combat in Indonesia, after they were delivered to the Royal Netherlands East Indies Army. A modified CTLS was also briefly in service with the Dutch that featured a small turret with a 37-millimeter main gun.

Light Tanks Today

The Marine Corps was the first and last branch to use them—and more recently, has started retiring all their tank battalions, rotating leathernecks with a tanker Military Occupational Specialty elsewhere. This move, though controversial, is how the Corps prepares to wage a fight in the Pacific against China. And there is an argument to be made in favor of a tankless Marine Corps.

The M1 Abrams has absolutely no amphibious capabilities and would therefore not be suited to a World War II-esque island hopping campaign, should a conflict with China break out. But would there be a need for a lighter, more amphibious tank in Marine Corps service? There just might be, yes. Germany still fields a small odd-ball tankette—maybe it’s something the Marines could use.

Caleb Larson is a Defense Writer with The National Interest. He holds a Master of Public Policy and covers U.S. and Russian security, European defense issues, and German politics and culture.

This article first appeared in September 2020.

Image: Wikimedia Commons