I'm glad you brought that up. I think you're right that our personal security can have an effect on which people we perceive more or less as "scary" or "bad", or for whom we are more or less capable of feeling empathy.

Also, the more we know about a person, the more we might understand their motives. In the case of someone who kills purely for pleasure, that might not assuage us much. But in most cases, we can probably realize that people's crimes were done out of desperation, or within a particular extreme or limited context (e.g. a soldier killing an enemy in a war), such that we don't feel like they pose a threat in the current context.

Your article about eating dogs is great! Touches on a lot of the same points I'm making here.