When I was growing up on the farm, we used to have a few rabbits. I imagined how a caged rabbit would react if I put him out on the lawn where he'd be free. Surely he'd take off like a bullet. So one day I tried it. I carried the rabbit outside in the middle of the yard, and slowly backed my hand off. Nothing. I stood up and watched, and the rabbit just sat there, nibbling a bit at the grass.
His whole life had been in a wire cage. His ancestors lived their lives in a wire cage. All the rabbits he knew lived their lives in wire cages. He had no concept of freedom, and the absence of the cage made him nervous because the cage kept predators away.
I've thought about that a lot when encountering gun owners from blue states who didn't see a big problem in restrictions on firearm ownership.