Disagree on a point
Northern Ireland, as bad as it was, pales in comparison to the estimated 100 million people murdered by communist governments during the 20th century. Remember, communism was officially atheist, although it seems their form of government was their religion.
I personally believe that politics represents the worst aspects of humanity. Even the Crusades of the Dark Ages were more political that religious in nature. In a world with some 6 billion people, politics is a necessary evil, but IMO an evil none the less.