Matt. 26:52: "Jesus said to him: ‘Return your sword to its place, for all those who take the sword will perish by the sword.’" (Could there have been any higher cause for which to fight than to safeguard the Son of God? Yet, Jesus here indicated that those disciples were not to resort to weapons of physical warfare.)
Isa. 2:2-4: "It must occur in the final part of the days that the mountain of the house of Jehovah will become firmly established above the top of the mountains . . . And he will certainly render judgment among the nations and set matters straight respecting many peoples. And they will have to beat their swords into plowshares and their spears into pruning shears. Nation will not lift up sword against nation, neither will they learn war anymore." (Individuals out of all nations must personally decide what course they will pursue. Those who have heeded Jehovah’s judgment give evidence that he is their God.)
2 Cor. 10:3, 4: "Though we walk in the flesh, we do not wage warfare according to what we are in the flesh. For the weapons of our warfare are not fleshly, but powerful by God for overturning strongly entrenched things." (Paul here states that he never resorted to fleshly weapons, such as trickery, high-sounding language, or carnal weapons, to protect the congregation against false teachings.)
Luke 6:27, 28: "I [Jesus Christ] say to you who are listening, Continue to love your enemies, to do good to those hating you, to bless those cursing you, to pray for those who are insulting you.
Just from those few scriptures and there are more it is quit clear to me that Jesus does not condon Christians to go to war and kill thier enemy.