Wait, I didnt know Role Playing Games were illegal!
In all seriousness though my stance is similar to yours but one step up... Any weapon allowed on US soil, to be used against US citizenry, by the government should be legal to own by a citizen.
That would mean either we would need to make it illegal to deploy the national guard against its own citizens or would need to allow US citizens to have military weapons. I'd be ok with either of these two outcomes.