In the 1986 film "Aliens", what is the name of the fictional military branch that the marines belong to?

In the 1986 film "Aliens," the marines belong to the fictional United States Colonial Marine Corps, commonly shortened to the Colonial Marines. The stored answer, "Colonial Marine Corps," identifies the canonical military organization and is a fair quiz answer.

The Colonial Marines are a future military force used for security, combat, and colonial operations across human space. In the film, Lieutenant Gorman leads a squad sent with Ellen Ripley to investigate the loss of contact with the terraforming colony Hadley’s Hope on LV-426.

Their military identity is reflected in the film’s equipment and language: the squad uses pulse rifles, smart guns, motion trackers, dropships, and a heavily armed assault vehicle. Characters such as Corporal Hicks, Private Hudson, Sergeant Apone, and Vasquez are all members of this unit.

The wording is sometimes confused with "Space Marines," a generic science-fiction term used in other franchises, or with the real-world U.S. Marine Corps. Aliens’ force is fictional and specifically called the Colonial Marines or United States Colonial Marines. James Cameron’s film was released in 1986 and expanded the original Alien story from isolated horror into military science fiction.