They wanted people available to repel invasion or other insurrection. Since there was no real Regular Army at the time, and no logistics to issue a mass quantity of arms, they wanted people to have weapons of their own. Handguns aren't that useful in battle anyway. I really don't see how you derive the conclusion that the founding fathers wanted all americans to have the same state of the art weapons as the regular militia. I am not saying that all hunting rifles should be confiscated or anything.
Modern papers are automated, some are even electronic.
But their technological advances don't mean that the first amendment doesn't apply to them. It also doesn't mean that radio, television, the internet, and magazines with color photographs, aren't protected as well. Actually, I am not assuming anything like that. They wanted people available to repel invasion or other insurrection. Since there was no real Regular Army at the time, and no logistics to issue a mass quantity of arms, they wanted people to have weapons of their own.