Few things regarding The Troubles. First, it was awful, and against what either of the religions profess. Second, Catholics and protestants might consider each other ‘Christians’ in a broad sense (some of the latter might not grant that to Catholics, who conder the protestant churches heretical), but not the same faith. While the conflict had some historical religious roots, by the 20th century that was incidental. The ‘catholic’ side were socialists, if not outright communists.