The whole point of the 2nd amendment is to be able to form a militia if the government gets big and tries to take your liberty. You don't need artillery, just a small percentage of resistance like the small percentage that fought the british
How can you promote handguns, but not RPGs (if the logic of promoting handgun availability is that it enables resistance to tyranny)? Or, looking at it the other way, how can you ban RPG/IED purchases, but not ban handguns?