I forgot, defense of Christian lives and property was "murderous zealotry" during the Crusades....
The indiscrinate massacre of all Muslims in Jerusalem, be they man, woman, or child, combatant or invalid, was murderous zealotry at its most vicious. So was the mass killings of Jews in Germany by Crusaders passing through on their way to the Holy Land in 1096, and the remaining 200 years of the Crusades provide plenty more examples - unless you feel that Christianity needed "defending" from the little Jewish children of Mainz.