If not for sin, we would be living in a world order. In a sinless world, man would obey natural law and be a united brotherhood.
We will live in the kind of world the Pope is talking about after the final judgment; but it is still a goal we should all strive for daily. If everyone did the right thing by every person encountered, this would be heaven on earth.
Our choice to sin affects everything. Some believe that this is why Satan defied God: God chose to create us with free will and Satan saw us as a flawed creation. He couldn’t accept God’s will about us.
Your comments are very useful and insightful.