"You became brothers & sisters pledging allegiance to the same timeless principles, joined together in a common mission: to protect our country, to defend our people, & to carry on the traditions of freedom, equality & liberty that so many gave their lives to secure."
If brothers cannot become brothers in arms when it comes time to defend their families and themselves, then they deserve no peace, but deserve to be pieces.
There is no NT/OT difference here. There is no harmony with the devil.