Mobile Infantry (Starship Troopers)

The Mobile Infantry (MI) is a fictional military force in Robert A. Heinlein's novel Starship Troopers. The MI appear in the movies Starship Troopers, released in 1997, the 2004 sequel, Starship Troopers 2: Hero of the Federation, the 2008 film Starship Troopers 3: Marauder and the TV series Roughnecks: Starship Troopers Chronicles. The MI is portrayed differently in each version, a constant element is their depiction as space marines, soldiers who undertake infantry operations after insertion onto a planet from space. The MI trademark powered armor of the novel appears only in the last films as rough prototypes.

The Mobile Infantry is part of the Terran Federation military. In the original source novel Heinlein uses it to compare and explore the differences between two races, one of free individuals (humankind) vs. a collective race (bugs). Heinlein's MI is a volunteer force that resembled the Roman Legions, or modern day US Marines.

The Starship Troopers role-playing game (RPG) developed by Mongoose Publishing and the Starship Troopers first-person shooter (FPS) make an amalgamation of the Mobile Infantry of the movie and the Roughneck Chronicles series with light infantry from the movie being supported by elite power suit equipped warriors for elite operations. The "light troopers" were envisioned as cheaper alternatives to the more fully trained, power armored, "true" Mobile Infantry.

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