What about "You shall not kill". There are quite a tradition of exceptions. In self-defence (generally accepted), in war (widely accepted, although not by everyone, and always with limitations such as requiring the war is just), and for judicial punishment (although again only as a necessity, and the Catholic Church has said its not necessary under modern circumstances).

The bible doesn't say that. It says "you shouldn't murder" where "murder" means "kill a human without just cause". The standard "thou shalt not kill" is a bad translation, nothing more.

You can tell that it is from context as the laws just after that mandates a LOT of killing. For being "a witch" for example (which I assume is another mistranslation).

Violence can be correct in self-defence and war, but being in self-defense is not enough to justify it alone.