BS liberal crap. You can't tell a man that he can't be a Cristian and fight or do anything else for that matter. Christians don't tell atheists they can't fight so there should be no problem...but of course there is because everything has to be about appeasing Christianophobics.
Yeah, but do I really have to be Washed in the Blood of the Lamb to close with and kill America's enemies in ground combat?
You can’t tell a man that he can’t be a Cristian and fight or do anything else for that matter.
Actually, it can be done for without law there is anarchy:
U.S. Code: http://www4.law.cornell.edu/uscode/
Includes the UCMJ: http://www4.law.cornell.edu/uscode/html/uscode10/usc_sup_01_10_10_A_20_II_30_47.html
DoD Ethics regulations: http://www.dod.mil/dodgc/defense_ethics/ethics_regulation/jer1-6.doc