United States Colonial Marines

The United States Colonial Marines (USCM) are a group of fictional space marines first introduced in the movie Aliens. They have taken a prominent role in the successive games, comics, and novels set in the Alien series.

The actual details of the force are not expressly revealed in the movies. An associated book Aliens: Colonial Marines Technical Manual by Lee Brimmicombe-Wood was published by HarperPrism in 1996 and describes their force structure, tactics and weapons in some detail.

The USCM is the United States' "force-in-readiness", who are at all times ready to operate in environments far from home soil. By the year 2179, the force has roughly 165,000 Marines divided into four divisions, four aerospace wings, and numerous support groups. There is also a reserve division and aerospace wing with an additional manpower of approximately 50,000 Marines.

The USCM, along with the United States Army, are part of the United Americas Allied Command. The primary duty of the USCM is to maintain the security of the United Americas signatories and colonies, and serves as the vanguard of any major operation.

The fighting groups are organized into three Marine Space Forces, each has primary responsibility for security in their areas. A Marine Space Force consists of one or two Colonial Marine Divisions and a Colonial Marine Aerospace Wing, for ground and air/space combat respectively. They are:

The Colonial Marines are best known for their use of the M41A pulse rifle, a futuristic assault rifle with an underslung grenade launcher, and for the M56 smart gun, a large computerized and target-tracking machine gun which is actually worn by the user using a sophisticated harness mechanism. Also featured in the movie Aliens are the M240 flamethrower, the M4A3 pistol and the UA-571C sentry guns. The Colonial Marines also employ a variety of land and aerospace vehicles, including the M577 A.P.C., the UD4L Cheyenne dropship and the Conestoga-class assault-transport ship Sulaco, all of which are featured in the film. A variety of other tanks, artillery and anti-aircraft vehicles are also mentioned in the Colonial Marines Technical Manual.

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