But they are invincible!

All of this indicates that Leviticus 18 is describing the people of Canaan in terms of a well-known ancient Near Eastern trope about invincible barbarians destined to be destroyed by the gods. Despite the portrait of the barbarians, their status as living outside the ordered world, and their destiny of destruction, the trope is never used as an excuse to destroy them on behalf of the offended gods (what we would call holy war) because the gods reserve the right to deal with them themselves. It is also never used to justify attacking the barbarians and taking their resources (implied by the English word conquest), because attacking the barbarians militarily is suicide. Normally the trope is employed to rationalize losing battles (not winning them) and avoiding enemies (not assaulting them). This means that Israel would not have used the trope to justify going to war, and if Israel would not have used it, an interpreter of Israel’s actions cannot use it either. Likewise, the interpreter cannot use the reference to make any claims about actual behavior of actual Canaanites, because law treatises (and violations thereof) do not describe actions per se, and the trope of invincible barbarians does not necessarily reflect actual observations.— The Lost World of the Israelite Conquest, 144