The root problem is man trying to decide if HE approves of GOD....as if the God who created the entire Universe is someone we can comprehend and judge!
My time In Afghanistan in 2007 convinced me God probably had good reason and just cause to exterminate the Canaanites. In any case, it is certain that a God who can create a universe is likely to know more about the situation than modern man does!
This just shows the pride of modern man, and sets us up for just judgment by the God they reject.
"Barbarism is that which prevailed from the days of Adam down through ten generations to the time of Noah. It is called barbarism because of the fact that in those times men had no ruling authority or mutual accord, but every man was independent and a law unto himself after the dictates of his own will." (John of Damascus, "The Fount of Knowledge," cited in Political Apocalypse, Ellis Sandoz, p. 131)