Fighting against people, to some degree, is inevitable. There are people who will stand in the way of the kingdom of God and that alone will bring us to a place of contention. What we must be careful of is that we never find ourselves in conflict with God! That is a fight that we cannot win!
Solomon and his offspring found themselves in conflict with God - they had turned away from the path God had laid out for His people. This resulted in the division of the kingdom and ultimately to its demise. Nebuchadnezzar found himself in conflict with God and that landed him in a position where he was completely humbled and broken.
Sometimes, God allows us to get knocked down, to be humbled, to have our world broken and destroyed - not to punish us or make us suffer, but to give us an opportunity to rebuild ourselves in accordance with His will which is always a better path!
Scriptures used: 2 Chronicles 13:10-18, Acts 5:34-39, Exodus 14:13, Daniel 4:28