The founding fathers were very bright people. They also knew what they didn't know and couldn't forecast. Thus, when they wrote the Constitution, they stayed with broad, general guidelines, not specifics. And it's worked. People that have loved and hated the document can't seem to come up with arguments against it.
So, the Dads realized that the instrument they were building would on occasion get out of tune, and they put in a process to fine tune it using the court system. On a few occasions, it's been given a heavier overhaul with additional constitutional amendments.
And it works. Whenever law enforcement comes up with a new tool to look into our privacy, it ends up in court and rules are made. When new forms of media arrive, policies are adjusted to fit speech and press freedoms (the Wisconsin state Capitol is the exception--the Constitution of North Korea applies there). I can believe in any religion I want, but I can't sacrifice a human in the process. Don Imus can make his "Nappy Headed Hos" remark and, while it cost him his job, it did not cost him his freedom. Remind me sometime to tell the story of the time I shouted "theatre" in a crowded fire. Great story.
With one exception. Somehow, the Second has been declared the Constitutional version of the Shroud of Turin. If anyone dare suggest that it is time to "tweek" the Second, you are labelled all sorts of names, none of which would be said in polite company. Your patriotism, your intelligence, your work habits and the species of your parents will all come into question. Want to ban something that someone prints? HELL YEAH, because the First amendent didn't cover that! End polygamy? Got to, because the freedom of religion was written before Mormonism was founded. But...don't touch the Second!
When the second was ratified, the first line weapon was a musket. The range was 50-100 yards. The expectation was that the average person could fire 3 rounds a minute. Hardly compares to weapons of today that I could buy in minutes, legally, based on a clean criminal record and the fact that I have yet to be proven to be insane. Yet.
So, why is the second the only one that can't be touched? Well, there's the argument that a well armed populace keeps the other rights protected. Hogwash. The U.S. military took the Iraqi military apart like it was nothing, and it was equipped with jets, tanks, and all sorts of things that most people don't have in their garages. If "the gobberment" wanted to take military control of the country, there's nothing anyone has in their closet to stop it. Red Dawn was fiction. Get over it. You aren't stopping a missile fired from a drone with a rifle. Sorry.
But mostly, it's because the NRA is funded by gun makers, and they don't want regulation. There's another group of people that want to sell us stuff we want but shouldn't have, but they don't have nearly as good lobbyists and PR people. They are called "drug dealers". Here's the other dirty little secret about the NRA. They don't actually care about what their members want. Know why? Because not enough care enough to quit, and because the NRA, this most American and patriotic of organizations, is run like the old Soviet Politburo. Members don't vote. Members of the board select other members of the board, and right now, the members that represent gun makers are selecting other gun makers. If they were dating, soon the entire board would be made up of dwarf, hunchbacked albinos for lack of any depth to the gene pool.
So, we have a group of private interests that are controlling a group using Soviet tactics that advertises that they are supporting the common good. Gee, sound familiar in some other facets of life, people?