Greg - watch the movie. Your indignant about the wrong parts of the plot. ;-)
He's not with the military anymore, and is basically a mercenary, but can only be such because his DNA happens to fit; has nothing to do with his injury. The galaxy-crossing spaceships in this case aren't put together by the country or any other governmental body, but are in fact mining ships doing this for profit, along with some science investment that allows these avatars (but only because the profiteers believe they will help make them money).
There are many things that happen in this movie that people can perceive as an insult to the military, but this particular one likely isn't in the top 20.