It is often quite terrifying to realize that “good” is not “perfect”, and that “did something bad” does not necessarily make one a “bad person”. My take on why is that it says more about us, and about the society we portray in this age.
To the societal aspect, we seem to have a strong desire to “other” anyone who does something bad, and the worse it is, the more we have to other them. They are a different political group, a different race, a different gender, a different religion, not a “real man” or a “real woman”, and ultimately, if they push hard enough, they are monsters or something other than human. Whatever we need to do to make them not us, we will do, especially if we can find a way to benefit from the action. We do not want to be reminded that they are us, which brings us to what it says about us.
We are all capable of disturbingly deep depravity. Yes, all of us. That means I am and you are. So is your sister, mother, birth, uncle, father, favorite politician, actor or actress. We, in my view, do not want to admit this. We do not want to understand and accept that we are all capable of doing bad things. We build up an image of how good we are, often, I think, to avoid recognizing our innate capabilities for doing bad.
Thus, to recognize a person we think of as “good” doing something we consider “bad” means confronting the specter of our personal and unexplored capacity for bad. It is, in part, cognitive dissonance because we place such a mental barrier between the two that it is almost blinding when it hits us unavoidably.
Accepting the notion that good people can do bad things means we have to accept that bad people can do good things, as well. We disassociate with these cases for the same reason. It also requires us to accept that we, too, are capable of doing bad things.
When we lose that, when we think that only bad people do bad things, we suffer. We create the conditions for lack of compassion. It is easier to be discompassionate, mean, or violent to people whom we can not accept as “like us” than it is when we realize “there but for the grace of God, go I.” It is a far more difficult thing to treat people in those ways when we can envision ourselves doing it.
Finally, by not coming to terms with our capacity to do wrong, we lose a strong protection from doing wrong. The greatest of evils and atrocities committed against humanity were done by those who believed they were doing good. Those people had built up such a combination of othering bad people and refusing to understand their own capacity for doing ill, that they were unable to see the wrong in what they were doing. They could justify it as “for the common good”, “social justice”, or by casting the other as so evil victory must be achieved by any means necessary.
Once you’ve truly come to terms with what you are capable of, it puts such a fear in you that you wind up creating a sort of internal watchman on your behavior. Knowing you are capable is the first step to keeping yourself from doing it. So accept that good people can do bad things, and still be good people. Internalize that bad people can do good things, and remain bad people — but they are still people. Ultimately, plumb your own depths (mentally, don’t actually do the things you come up with) to understand your own potential for such things. Then recognitions like that are no longer scary or terrifying, they are obvious and somber.