This is a good, moral proclamation by this Pope, refreshingly unambiguous and rightly apolitical.  Let the nations (Caesar) figure out how to achieve peace among themselves, and let the Church be a guiding light for them.  Notice he did not say, "Who am I to judge," when it comes to what is the right and moral act.  People will do what they do, the Church can only try to help them do the right and moral thing by taking a strong, unambiguous stance.