You said: "Thanks for clarifying the distinction. I appreciate your viewpoint. At the same time, I'm afraid I am as firm in my starting assumption that evil is not inherent in human beings, as you are in yours."
I think you have misunderstood my point of view. But then, looking back, I think it is easy to come away with your impression, so I'm glad you brought it up so that I can set things straight.
I believe that:
1) The overwhelming majority of (but not all) people are NOT inherently evil.
2) The overwhelming majority of (but not all) people are, under the right circumstances and external pressures, capable of doing horribly evil things
3) There is no contradiction between beliefs 1) and 2)
How is this possible? Social psychologists distinguish between situational attribution and dispositional attribution. The former explains how an individual can carry out actions or behave in highly uncharacteristic ways due to external circumstances, whereas the former explains behaviors and actions that are characteristic of an individual. So if belief 2) is assigned a situational attribution, then there is in fact no conflict between it and belief 1). This is just psychological jargon for something you said yourself:
"So I think it's the structure of social systems -- external coercion -- that leads individuals and groups to evil, not innate characteristics."
So, you see, our perspectives on this point are not as far apart as you might have thought. The points on which I disagree with you are as follows:
1) Not all coercion is external. If it was true that all coercion was external, then someone who is coerced into committing a certain evil action repeatedly would have to be coerced with the same force into doing that action each time. This disagrees with the available evidence. For instance, there are records of Nazi soldiers assigned to exterminate civilians who were initially highly reluctant to do so. However, after they had already killed a few, their reluctance faded. Most likely, there was an internal rationalization mechanism along the lines that since they had already crossed the line, it did not matter to resist any longer. In my view, rationalizations, willful ignorance of evidence in contradiction of one's convictions, biases, internal justifications by means of fallacies, delusions and other forms by which the mind leads one to behave uncharacteristically are internal forms of coercion.
Moreover, there is a certain subset of the population who are NOT inherently evil but are unfortunately more prone to performing these kinds of mental maneuvers on themselves and as a result are more easily potential cases that illustrate the "banality of evil". You may want to take a look at the first few chapters of Altemyer's book.
2) Not all people are inherently good. If you really believe that no one is inherently evil, then your belief is again in contradiction to the available evidence. If nothing else, the stereotypical serial killers who kill purely for the joy of it present stark counterexamples to that belief.
3) Each of us should openly admit to ourselves that we are, under the right external pressures, capable of committing horribly evil deeds. I believe that if I am willing to honestly admit that to myself, then, should I ever find myself in a real-life Milgram-experiment type situation, I will be much more likely "catch myself" doing something evil before I actually carry it out. If, instead I desperately hang onto the notion that I am inherently good, I may be much more prone to activate the rationalization, self-deception etc. mechanisms in my own mind which make it more likely that I will actually carry out the evil deeds.
In fact, this underlies something you said yourself:
"I think people do evil things because they believe they are doing good."
I think this holds for almost all followers of evil and almost none of its leaders. Again, it is important not to confuse the two types of situations.
A major point of my essay was the "social structures" giving rise to "external coercion" which lead people to "do evil things because they think they are doing good" may not come about randomly or at least inadvertently, but rather are built up intentionally and gradually by people who understand very well that what they are doing is not because it is good but because it satisfies some of their wants and desires.
At this point, let me pull out in the open what I think is your real objection and confront it head-on.
I think that you find the notion that a minority of the population is singled out as, at least in some sense, "evil" highly disturbing and uncomfortable, and you would rather believe that this was not true.
Let me emphasize that I completely agree with you! If we associate a certain group of people with "evil" we are taking the first step towards dehumanizing them, and thereby, we are taking the first step towards dehumanizing ourselves. In other words, acknowledging that this might be true suddenly causes one to be immediately confronted with a profound and very difficult ethical and moral dilemma. I understand this, had to grapple with it and acknowledged it and my inability to come up with a good answer (at least at the moment)in my essay. On the other hand, if this is really true and I deny it because its consequences make me feel uncomfortable, I have failed in my search for truth. We all like to think of ourselves as reasonably objective and rational, but the true test is when we are presented with evidence that contradicts our most cherished convictions. Moreover, if this is true and I deny it, I may make myself more vulnerable to the consequences of my denial.
The way I have tried to deal with this is not to let the ethical conflict stop me from investigating this possibility mentioned in my essay, but at the same time openly acknowledge that an ethical conflict exists and that it needs a solution. Some of the things one could do, and I am attempting to do for now, are
1) Minimize the emphasis on the moral and ethical concept of evil and maximize the emphasis on medical and scientific concepts disease and selection
2) Refrain, in the absence of a medical diagnosis, from calling specific people psychopaths unless there is clear and generally agreed upon evidence that the person in question most likely did not have a conscience (e.g. Hitler, Stalin). In my essay I did name some specific persons at the end, but if you read carefully you will see that I only described their actions and did not label them.
3) Refrain from a description of the situation in anything but the most objective language possible.
This got to be a very long response, but I hope that now things are really clarified.