Matthew 12:25 And Jesus knew their thoughts, and said unto them, Every kingdom divided against itself is brought to desolation; and every city or house divided against itself shall not stand:
History has proven this to be true. You do not have to be a believer to see it. Division unfortunately is a product of free will. Even if peace reigned throughout all the earth in loving concern for the wellbeing of the planet, division would still exist.
Division via freewill does not exist because our treaties of the mind but rather the condition of our hearts. Do you love God with all your heart, mind, soul, and strength? Then you are One with God. The other is one with the world. Doing the right thing for the love of the world is still on the other side of a world divided.
Peace on earth does not exist and history tells us that peace among men is illusionary. Every treaty has a side, an agenda, and a reason to keep the peace. Those things change, always have, always will. So if we cannot make a fragile peace, how can we live with hostile world?
Love God with all your heart, mind, soul and strength. Let love rule in your heart and leave the rest to God.
2 Corinthians 6:6-10 By pureness, by knowledge, by long suffering, by kindness, by the Holy Ghost, by love unfeigned, By the word of truth, by the power of God, by the armour of righteousness on the right hand and on the left, By honour and dishonour, by evil report and good report: as deceivers, and yet true; As unknown, and yet well known; as dying, and, behold, we live; as chastened, and not killed; As sorrowful, yet alway rejoicing; as poor, yet making many rich; as having nothing, and yet possessing all things.
The left and right side of the body is for balance, not division. We are still One.