Maybe what you're missing from the movie is at the 2-hour point, Remer is home in the states after his tour, shopping for cereals, and is baffled by the multitude of choices...
...he realizes the inherent uselessness of his life as a citizen...then reinlists for a 2006 tour which ends the movie...it was quick, and subjective, but reinforces that his character is an adreline-junkie....
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"My people (the real Americans- descended from the original Angle-Saxon pioneers)"-Coke S.