All you have to do is to say that your group is pure and good, eligible for a full life and for some kind of eternal meaning. But others like Jews or Gypsies are the real animals, are spoiling everything for you, contaminating your purity and bringing disease and weakness into your vitality. Then you have a mandate to launch a political plague, a campaign to make the world pure. It is all in Hitler’s Mein Kampf

Ernest Becker