I would say that a lot of what you see isn't representative of the Americans I know. With one exception, I've never met anyone who in the US who was a 'gun nut', although this might be to do with the demographic as most of my friends are palaeontologists or interested in palaeontology. In most of the US that I've visited I didn't give the presence of guns much thought as they weren't in the open even in N. Carolina and Virginia (although the museum had a 'no guns' sign on the entrance doors).

Whist out in the field we found evidence of gun use though, including 9mm rounds from an automatic weapon, and shot up objects like plastic bins etc.

I love the US, and outside of the cities the people are brilliant, always very welcoming, chatty and refreshingly polite and it hurts to see the country suffering the way it is.