What difference does the time of infestation matter? Christianity overtook the Roman Empire when Constantine abandoned the Greek commitment to reason, mathematics and science for the miracles and magic of an exotic "new-age" (for the times) mind virus. Shortly after that the west completely forgot the "western values" that defined the Greco-Roman culture and entered into the dark ages. "Western Values" were re-introduced to Europe by Muslims during the Crusades. The rediscovery of classical Greek mathematics, science, philosophy and drama propelled Europe into a renaissance of those values. "Western values" were not restored to Europe (because Christianity still dominated the Renaissance) but they weren't lost either. European culture became an amalgam of the old western values of the Greco-Roman period and the new Middle Eastern values found in the distinctly Middle Eastern book known as the Bible. The Middle Eastern influence runs very deep in the modern western world, especially the U.S. It is the life-blood of the Christian religion. The differences between Jews, Christians and Muslims are miniscule. They hate each other because they have so much in common. People who have truly different beliefs from each other are generally indifferent to each other. Strong disagreement on religion requires differing perspectives on a common historical issue to which both parties are strongly committed. You hate them because you are like them.