Well, I didn't have much time today, but when you toss out the main questions of violence and fairness of Holy War as I've been doing, you're not left with much for this chapter. So, I figured I try for a quick one. Actually, the two remaining notes here are both going to relate back to things I've already discussed.
First of all, the SAB notes some cruelty in the fact that Joshua houghed, or hamstrung, the horses. Honestly, I'm not sure what the deal is. Apparently, they were ordered to do so by God, and it was related to the destroying of the chariots. This actually goes back to the issue of Holy War in that God wants to make sure that they keep very little of what the Canaanites leave behind. It seems that chariots were among the things that God didn't want them taking, although we are not told why if this is the case. It may be that God wanted them to fight without what would have been more modern techniques of the time. If they fought with chariots, they'd be tempted to say "Isn't it great we have chariots on our side?" rather than "Isn't it great we have God on our side?" Even with that speculation though, I don't understand this method. If they were to keep the horses for themselves, then they ought to not harm them. If they weren't keeping the horses, why not just kill them as humanely as possible? I may be missing something, I don't know.
The only other thing here is the issue of the hardening of the hearts of the Canaanites. The SAB says, "...God hardens their hearts so that he can have an excuse to kill them." Well, that's right, actually, but it's not quite as arbitrary as it sounds. I discussed it way back in Exodus in the matter of Pharaoh. There comes a time for many people, if not everyone, that God will cause them to be set firmly in the way that they have already chosen. If you really want to hate the Bible, then God will let you; and in fact, He is likely to find a way to make you so strongly hate the Bible that He can use your hatred to bring glory to Himself. The Canaanites were hostile, and God gave them over to their hostility so that the war would proceed according to God's plan. God works that way sometimes, and if you don't like it, He's more than content to let you not like it.