When the Nephites decided to ignore the advice of Mormon and avenged themselves on the Lamanites, they set themselves up for a real disaster. Mormon tells us what happened.
The survivors from the city of Desolation fled to a nearby city closer to the seashore which was called Teancum. If the Nephites had left well enough alone they would still be in their headquarters city of Desolation and the lives of many Nephites would have been preserved. Furthermore their wives and children who were taken prisoners would still be free.