Yet another casualty of a Biblical mistranslation. The Commandment is "thou shall not murder." ....quite a distinction.
Um, no. The KJV (which would more than likely be the translation used as it is through large parts of the South) says 'thou shalt not kill'.
Also note that when King Saul went to war with Amalek, God told him to "smite Amalek, and utterly destroy all that they have, and spare them not; but slay both man and woman, infant and suckling, ox and sheep, camel and ass." (1 Samuel 15:3)
I think that's a pretty good indicator God distinguishes between "murder" and "war".