If the Kingdom isn't of this world, then our citizenship isn't of this world. If that holds true, then you shouldn't arm yourself to fight to maintain it.
Remember what the King told Peter: Then Simon Peter, having a sword, drew it and struck the high priest’s servant, and cut off his right ear. The servant’s name was Malchus. So Jesus said to Peter, “Put your sword into the sheath. Shall I not drink the cup which My Father has given Me?”
The King uses angels to fight our battles. Citizens of the Kingdom trust in God's Word. Christians choose to fight their own battles. ...Then he said, “Don’t be frightened, Daniel, for your request has been heard in heaven and was answered the very first day you began to fast before the Lord and pray for understanding; that very day I was sent here to meet you. But for twenty-one days the mighty Evil Spirit who overrules the kingdom of Persia blocked my way. Then Michael, one of the top officers of the heavenly army, came to help me, so that I was able to break through these spirit rulers of Persia. Now I am here to tell you what will happen to your people, the Jews, at the end times—for the fulfillment of this prophecy is many years away.” (read the whole story: Daniel 10 )
John 18:36 John 18:10-11 Daniel 10:12-14