I have spent time with mass killers, warlords and death squad leaders as a reporter in Latin America, the Middle East, Africa and the Balkans. Some are psychopaths who relish acts of sadism, torture and murder. But others, maybe most, see killing as a job, a profession, good for their careers and status. They enjoy playing God. They revel in the hypermasculine world of force where theft and rape are perks. They proudly refine the techniques of murder to snuff out one life after another, largely numb to the terror and cruelty they inflict. And, when they are not killing, they can sometimes be disarmingly charming and gracious. Some are decent fathers and sentimental with their wives and mistresses. They can dote on their pets.