Next, you can deal with the fact that it's not just Canaanite nations under the genocide threat -- e.g. the Old Testament's own Jihad call in Deuteronomy 13. Or point to the New testament passage that invalidates any of this for Christians. *Lunatic*, n. One whose delusions are out of fashion.
I don't understand the relevance of the age of the text to your approval of genocide and slavery on "moral grounds", unless you think genocide was right back then but not now. *Lunatic*, n. One whose delusions are out of fashion.