What Sun Tzu talks about is accepting reality and working with it. This has always been the true Warrior's way. The most important aspect of a Warrior's perception of reality is honest self-evaluation. "Dishonesty to oneself is bad discipline." I accept my limitations, and either make them work for me or do what I can to turn them into advantages. Each person has natural qualities and abilities as well as certain faults and limitations.
Jungian psychoanalyst Robert Moore put it this way:
"A man who appropriately accesses the archetypal Warrior draws upon enormous resources that enable him to live an empowered life in the service of his fellow creatures... When the Warrior is on-line, we feel a rush of blood and adrenaline, a quickening heartbeat, and a sense of something momentous about to happen. We feel mobilized for action, ready to charge forward to meet life head-on. Our daily concerns fall away from us and we are swept up into a kind of ecstacy in which we see ourselves and the world with a sharpened focus and clarity. Hidden rage is transmuted into energized courage. We come into touch with the great mystery of life and death, and we feel a strange sense of pleasure in the midst of pain."
So what should a spiritual warrior do? What is his job and responsibilities? To first accept responsibility for themselves and to overcome all spiritual handicaps. And then to fight for what is right, in accordance with the Creator's will. For more info I would read these books, one is new and one is older.