There’s been another attack on Christians in Cairo, this time on St. Mark’s Coptic Orthodox Cathedral, where 25 pounds of TNT somehow slipped past government security guards and killed at least 25, mostly women and children, and injured another 49 so far. The Coptic Orthodox, led by Pope Tawadros II, are the largest denomination in Egypt and North Africa, and have been independent both of Rome and of Eastern Orthodoxy since the Council of Chalcedon in 451. The church traces its founding to St. Mark the Evangelist. (Amr Abdallah Dalsh/Reuters)