In this world, there is very little clear vision. One pious person's vision of a just society may differ radically from another's. We may drink the Blood of Christ from the same Chalice, but when it comes to politics, have very different views. We are all quite blind.
However, when we love those who disagree with us, we are beginning to manifest the justice "from above." A great deal can be accomplished in this world, but it is not by everyone having the same opinions or the same politics. Genuine societal change happens when we listen to those we disagree with, when we refuse to demonize our enemy.
Life in this world sucks, but the Kingdom God is manifest in and through us who live in this world.