Or maybe viewing from the outside allows you to see certain nuances.
You're spot on with the culture being the primary problem. The NRA could be a big help by taking the position that the laws would help the law biding gun owners by keeping the weapons out of the hands of baddies. But they've staunchly maintained a fer us or agin us position, because that makes them the most visible leader of the fight for the common man against the big bad government/eastern eggheads, which makes the money flow into their coffers.
Trump learned to tap into that same common man defense to attract the disgruntled, but for personal aggrandizement rather than wealth. While the NRA wants to turn back the clock to the 1880s, Trump's promising to turn back to the 1950s, it says so on his hat.
Of course nobody in either camp mentions the 1880s was an era of lawlessness and high personal danger, and 1950s was an era of big government, and strong unions.