Why does society often tend to blame the victim?

I notice this is a trend all over the world. Women who are raped whilst drunk are often blamed for being raped for having one too many... In certain countries even little girls who get raped are accused of asking for it. When Pakistan bombs India, India is blamed when they fight back. When Palestine bombs Isreal, Isreal is blamed for fighting back. When children who are abused emotionally or physically by their parents fight back, other family members try to blame them for not being quiet about being abused by their family members.... Millions of examples. What is it about human nature that tends towards blaming the victim rather than the perpetrator?