There is a minority of the country that is over represented in the media that are as you describe but the vast majority are not like that. Also, making vast generalizations about a huge diverse population of people is generally bad form.
Are those that support people to own and carry guns a minority?
Edit: Well, that came out a bit wrong, I think. I didn't mean to support or not support OP. I was just curious.
Assuming your number is accurate, that is still a minority of the country. They are large enough to have _some_ influence by virtue of being concentrated in certain regions to elect idiots like MTG and Matt Gaetz but not large enough to represent majority viewpoint of the country. I will grant you that they are a big enough base to cause some problems such as the grid lock we see in congress right now.
Bringing it back to the original topic, these right wing gun toting idiots aren't the root cause (I'm not even sure you can point to one root cause, its a complex problem...) of our very real policing problems but they certainly aren't helping.
At the end of the day, it's a belief problem. It doesn't take a leap to understand how a belief system that agrees with "The only way our country can get through the crisis ahead is to get back to our traditional values, put some tough leaders in power, and silence the troublemakers spreading bad ideas," leads to police who act as tough leaders on troublemakers.
Like you said, it's a complex problem, and beliefs are a component.
1. https://pro.morningconsult.com/articles/right-wing-authorita...