A spectrum of advantages that allowed them a much greater margin of error and tactical disadvantage

From Carnage and Culture by Victor Hanson Davis.  

In any discussion of military prowess, we should also be clear about  the thorny divide between determinism and free will. Throughout this  study, we are not suggesting that the intrinsic characteristics of Western  civilization predetermined European success on every occasion. Rather,  Western civilization gave a spectrum of advantages to European militaries  that allowed them a much greater margin of error and tactical disadvantage—battlefield inexperience, soldierly cowardice, insufficient numbers,  terrible generalship—than their adversaries. Luck, individual initiative  and courage, the brilliance of a Hannibal or Saladin, the sheer numbers of  Zulu or Inca warriors—all on occasions could nullify Western inherent  military superiority.