It was, if memory serves, in relation to Eichmann that Hannah Arendt coined the now famous phrase "the banality of evil." Most of have seen more than one example of this idea in politics and everyday life. I always thought that it was a phrase that fittingly described Stephen Harper. He was a man with little or no charisma, he didn't seem to have any big vision, good or bad per se, he never seemed particularly bright to me, but was rather, like so many bad people, a very lucky person. He was ambitious, no doubt, but his ambitions always seemed petty to me and in the end seemed to be purely destructive tendencies driven by his own neuroses.
And many of us have known someone like this personally, someone who is actually unremarkable, seems fairly normal but is actually mean-spirited, selfish, and destructive for no particular reason other than some (perhaps deep-seated and undiscoverable) problem.
But evil is not always innocuous or banal. It often comes in larger-than-life, charismatic, individuals who somehow convince many people that their obvious nastiness is somehow an expression of something good. We often hear such people lauded by their supporters with the curious or dubious virtue: "he tells it like it is," or "at least he does what he says." I have always found this a strange kind of acclaim since doing what you say you are going do or 'calling'em like you see'em" hardly, in and of themselves, seem to be vitreous acts. I don't need to list all the terrible people who did what they said they were going to do. There are, of course, good people who are straightforward, but being straightforward (in and of itself) doesn't constitute a virtue, as everyone whose grandmother has purchased an horrendous new hat can attest.
But the real sad fact is that most larger-than-life evil people require an army of banally evil individuals in order to make their evil possible. Donald Trump may be fairly charismatic (if you like that sort of thing) and he certainly is larger-than-life, but many of his supporters are just average, drab, seemingly 'normal' people. I am not talking her about the loud-mouth, racists who thump passers-by. The media loves these types of people and gravitate toward them so we see them a lot. I am talking about the legions of quieter individuals who remain mostly in the background. These are people who have few ideas, no vision, little real experience of the world, and in most cases are shockingly short of common sense. But as banal as such people are, they are the real backbone of evil because they are the enablers without whom the larger-than-live evildoers could be no more than circus clowns.
When Harper attempted to enflame racist furor in order to win the last election, it was banal evil to which he was trying to appeal. The same is largely true of Donald Tump. Of course, he likes the loud-mouths and grandstanders; they bring him attention and enflame people. But he needs the average, quite individuals who hope to promote him to a real position of power where he can undertake evil that is not banal at all.