Some humans will be predatory monsters no matter what. No amount of parenting or social influence will change that (but it can indeed help in many cases and should be explored).

It is understandably difficult to accept this for the average human, but my extensive research on serial murderers (yes, I know that's an odd interest, but it is important) has led me to this conclusion.

We have to accept some level of evil in the world and mitigate it the best we can. Perfection and safety are myths in this reality. Prepare accordingly and then live life happily.