Letter writer Nelson Marans says that apart from the Holocaust there have been no mass atrocities in predominantly Christian countries in modern times ("Obama's comparison of medieval Christianity and modern Islamist extremism was hurtful," Feb. 11). Evidently he does not count Rwanda, where 800,000 people were killed in a hundred days in 1994. Based on its 2002 census, Rwanda is 94 percent Christian, predominantly Catholic. That the slaughter there was motivated by ethnic rather than religious hatred does not alter the fact that it was perpetrated by professed Christians, in flagrant violation of all Christian teaching. There will be time enough to talk about Christianity's advancement when practice begins to catch up with profession.