Mass gun ownership is a terrible idea... However I I was to live in many places in the US (from my probably wrong outside perspective) I would definitely want to own a gun and learn how to be effective with it.
If gun ownership in the US was to prevent a tyrant from abusing his office, I'd say now is the time to properly use that 2nd amendment... sadly, most believers in the 2nd amendment are on #45's side
Mostly, they've made me less sympathetic to police carrying weapons in their normal work, and especially to police bringing weapons to protests that aren't violent.
No change. Private citizens ought be able to own --in EVERY US jurisdiction-- all firearms make/models including full-auto, and local militias ought be able to have mortars, artillery, tanks. "Able to" being contingent on being a Full-Rights Citizen & displayed weapon competence.