The Bible teaches the right to life, when it says, "Thou shalt not kill." Just as the baby in the womb has the God-given right to life, so too entire nations have the same God-Given right to life.
The Bible permits the taking of human life under four circumstances: to protect one's self, or someone else, from murder; as a punishment for a capital crime; or in carrying out a just war. The 6th Commandment, taken in the total context of Scripture, does not forbid all killing. If it did, God would never have called himself a man of war (Exodus 15:3). The Spirit of God would not have attributed David's war-skills to God (Psalm 144:1). Jesus would not have allowed his disciples to carry deadly weapons (Luke 22:36).
Consequently, we learn that military service is a morally valid way to serve God. Jesus taught personal self-restraint in the extreme, but his teaching about turning the cheek was intended for the individual acting as an individual -- not to nations acting corporately as nations. Christ later taught that God has put the sword into the hand of government, to be used for the right (Romans 13:4).
But a Christian in military service will need moral discernment, courage, and vigilance. God condemned evil wars, and evil actions performed during war. God swore vengeance against the pagan nations around Israel, for their wars of race-hatred and plunder (Amos 1-2). God condemned Joab for treacherously assassinating Abner during a war, under false pretenses, while operating under the white flag of truce (II Samuel 3). God promised vengeance on Babylon for the wave of military terror they unleashed on the world (Habbakuk 2).
This is why we need the Bible seeded into all branches of the U.S. military. It isn't enough to be a powerful military. We must also have a virtuous military. The man who claims the U.S. military's only job is to "kill people and break things" speaks godlessly.
War is horrible enough, without our men and women being reduced to the level of savage animals. Our military men and women are not "killers." There are too many times in our history when our armed forces have been used for unjust purposes. God's will is that each nation's military should be defenders of the innocent, and deterrents against international thievery. This virtue comes through the Spirit of Christ and the teachings of the Bible.
Pray for the spread of the Gospel throughout our armed services, so that we have not just a powerful military, but a virtuous one as well.