In the background of much of the religious and political posturing we witness today is the belief that the world is full of people who behave badly toward others just for the sheer thrill of it. The implied assumption behind prevalent theologies and political rhetoric is that many, many fellow citizens and especially outsiders are wantonly evil and derive pleasure from inflicting pain on others. This very type of thinking infects a significant portion of the populace across the full political spectrum. This is never more evident than when like minded people come together to express their contempt for those who think differently.
I recall that the great philosopher, Socrates, was one of the first to conclude otherwise. He stated that in his experience and observation, people always did what they thought was right and necessary, no matter how evil it might appear to others. In other words, everyone was driven by needs and survival instincts which made it easy, some might say essential, to justify whatever action was taken to address those issues. Therefore, to the perpetrator, the action taken was necessary; and the end result was what counted, not the apparent ruthlessness of the means.
No one could miss the fact that in every conflict, both sides assume that they are ethically correct, merely doing what is required. Certainly there may be specific actors in the conflict who recognize and seize the opportunity for selfish gain; but, in the large, the combatants have been coerced into participation, indoctrinated against the "enemy", and/or actually feel the need to eliminated a serious threat. In either case the practice of evil for the fun of it is not an underlying motivation.
If there is an inherent evil to which humanity is subject, it is the very idea that we are commissioned religiously and politically to identify and nullify inherently evil people. I think this reality was in the background when God warned Adam about the Tree of Knowledge. That symbol represented the beginning of this age long quest by humanity to deal with human weakness by punishing one another in the name of righteousness.