I stand by what I said. That included a sentence after that single word. I son't think the woes of the first half of the 20th century were due to materialism or a lack of ethics. Religion wasn't the only belief that led people to commit atrocities. It, like others (communism for instance), was often abused internally more than externally.It is impressive of how you are able to sum up your intellectual superiority over Albert Schweitzer in one single word.
As for Isabel, she didn't treat muslims and jews similarly. She sent jews away very early while initially she let muslims have freedom of religion. Only pressures led her to change her ways with regards to muslims, so I say she was more anti-jew than anti-muslim. I don't think this is depicted at all in Civ IV, because the game lacks purging a religion, forced conversions and inquisition (unless you play with some mods). In the game, she could only be fighting muslims outside her kingdom, not inside. The unmodded game can't represent what she did at all in my opinion.