There is no quandary. I've provided evidence to support my view and you haven't.
The lobby group is called the National Rifle Association. Its magazine is called the National Rifleman.
Proper nouns because they are names of organisations. I repeat, there is no organisation, national or otherwise, of illiterates that Serious was referring to.
Don't often come across someone arrogant enough to argue with a dictionary, but there you are.