>>9848129It’s a Pavlovian response. You’ve seen how thugs and rapists have acted in videos, news and statistic, so now you associate their skin color with danger.
It could also be deeper than that. Throughout western culture, White is associated with purity and goodness while darkness is associated with sin and evil. Even the word “dark”. Look at them. They are “dark skinned”. Now consider how much the word “dark” is used to describe something evil across all forms of media.