I agree with that sentiment. But sometimes, some sort of "lawerly" or just plain regular folk thinking can insert itself. If the creator both calls one to war, and tells one to not intentionally kill, there will be a conflict in one's mind.
And therein lay the problem. The Creator is not the leader of any army today, men of the flesh are. Since the Babylonian captivity, the Ark of the Covenant which represents Elohim's seat of Authority that went before the army of Israel in war, has been no longer. No longer was Israel to war with the nations, it was to submit to the nations that Elohim placed over them. Isaiah prophesies this, also Jeremiah, Ezekiel & even Daniel prophesy the freedom removed from Israel, that until Messiah returns, Israel is to serve the nations, not be served by the nations.
And thus the reason Messiah teaches to love our enemies, do good to those who hate us and to pray for those who persecute us. There is reward for those who heed His Word and there are consequences for those who do not. It does not necessarily mean eternal death for those who do not, however, it surely does not include reigning and serving Messiah when He returns to rule this earth for 1000 years.