During the "Dark Ages" ... When the Christian Church was trying to destroy or limit all scientific knowledge, and persecuting those with different religious beliefs ... The Islamic nations were bastions of learning and tolerance. They maintained at least 1 of the "Great Libraries", until it was destroyed during the Crusades (by Christian forces).
Without the knowledge maintained by Islamic nations ... The Renaissance in Europe would not have been possible, when it happened. We would be hundreds of years behind our current level of technology.
Of course, without the interference of Christianity - we would be hundreds (or thousands) of years ahead of our current level of technology.
