"Now these are the nations which the Lord left, to test Israel by them, that is, all in Israel who had no experience of any war in Canaan; it was only that the generations of the people of Israel might know war, that he might teach war to such at least as had not known it before." (Judges 3:1-2)
Now there is an interesting verse from Scripture. Part of God's work in the heart of his people is to teach the men how to fight battles, to be prepared for war. Our God is a warrior!