When you read the Bible in its entirety over and over, a larger picture emerges than when you cherry-pick a single line. The Book of Romans is but one place that gives a defense for the power of the "king" to order the deaths of lawbreakers or enemy combatants. That is an entirely separate issue from a society promoting the efficient killing of unwanted innocents such as fetuses, people with disabilities or the infirm elderly -- and, inevitably, using government coercion to compel medical caregivers to perform such acts.
Secondly, the original commandments were written in Hebrew, and the word was "murder", not "kill."
So I guess, "Thou shalt not kill", for example, is not a moral absolute. It appears to qualify under some circumstances and not under others. Sounds a lot like "situation ethics" to me.