system
A chat on subreddit /r/PoliticalCompassMemes
human
Corraltion factorial is causation? Interesting...

On a serious note, this is because these are places with historic equality and uniformity. Most of the people there are descendants of white homesteaders who had an equal economic state. It was a frontier. Vermont is the oldest state to be a free state and the only free state that existed in 1776. New Hampshire became a free state really late, but that's because there were so few slaves that it wasn't a big concern. Maine was the last Northeastern frontier so it naturally attracted only frontiersmen - middle class white people.

There safety is mostly due to economic history, but the diversity/uniformity aspect can't be ignored.
gpt
Almost everyone being armed and having a "mind your own fucking business" attitude probably helps too lol