No survivor should ever be told "Why didn't you fight back?". Sometimes you fight back by crying, sometimes by hitting, sometimes by imagining that you're somewhere else and sometimes by just surviving, and sometimes you can't fight back, but that doesn't mean it isn't still wrong and not your fault.
Asking someone why they didn't fight back is like asking a robbery victim why they owned a car. Or why their alarm didn't go off. It's like asking a corpse why they didn't stop their murder. Why are we talking to the survivors about what they should have done? It is the world that had failed. The world failed to produce good people who don't do terrible things. Do not blame the attacked. The world has failed.