The minor prophet, Nahum, explains that God will not endure sin without responding. Nineveh repented of sins after Jonah preached to them. However, they returned to their sins. God judged Nineveh and the Assyrians, punished them and they were never a powerful city again. As it went for Assyria, our nation must also repent of our national sins. If we do not, we too will be judged and cursed.