Why We Have Guns
You never miss something until it's gone. The anti-gun advocates are varied in their purposes, but are uniform in their message: there is no reason to own a gun, or guns with certain attributes. When Mayor Bloomberg says, "we just don't need assault weapons out there", he is implying that there is no reason to have a weapon suitable for warfare. When Governor Cuomo says, "no one hunts with an assault rifle" and "no one needs ten bullets to kill a deer", he is implying that the only reason to own a gun is to hunt deer, and therefore the only types of guns people should have are the ones just suitable for hunting. The rest of the anti-gun advocates are perfectly happy to point out that no one in America needs to hunt to survive, implying that there is no reason to have a gun at all. Meanwhile, the gun rights advocates tiptoe around the primary reason for the existence of guns, and arms in general: to kill. Especially, to fight with and kill people, which is the exact reason laid out in the Second Amendment.
If you find yourself needing to shoot a third time, that deer is probably long gone, but when the only thing standing between your life and death at the claws of a grizzly bear is your ballistically insufficient 9 mm pistol, do you want to be limited to 7 bullets, or all the bullets you can fit in the magazine? When some intruders break into your house, or some muggers attack you on the street, you use as many bullets as the threat requires; the last thing you want to do is run out. A day spent exterminating prairie dogs might see a person fire hundreds of rounds, equally so while fighting an invading army. Exterminating a tyrant governor or self-proclaimed emperor might require many millions of bullets, or just one. It was the fight with armies and home-brewed tyrants that the founders envisioned when they wrote the Second Amendment.
The fears of the Founders were well justified. The first line of defense against an invading force would be the people, and most law enforcement was handled by the people, with sheriffs only incarcerating criminals after they were caught. Most importantly, as indicated when Benjamin Franklin said, "a republic, if you can keep it", the founders were well aware that the historical ends of democracies were tyrannies.
The Founders realized that the electorate might lose interest in politics, becoming uninformed or misled by corrupt journalists, no longer knowing or caring that politicians abuse their offices; or even worse, demanding that politicians abuse their offices. They foresaw that government might steal from the rich and give to the poor, and be rewarded with reelection; that the mayor of a city might dictate how much of something a person could drink, and be applauded for it by his city council; that a president might attempt to undermine the Second Amendment by fabricating a gun running crisis, and receive a pass from Congress; that elected leaders in Congress might advocate for the President to dictate and make unilateral appropriations; that the Supreme Court might declare that the Court does not exist to protect the people from the consequences of their elections; and that States and local municipalities might create specially armed and professional forces, organized under their executives, that look like armies (but somehow aren't), to impose their dictates enforce the law.
The reason we have guns is to fight against armies, possibly our own, to protect our life, liberty and property from thieves, that might even be our own government. Why would politicians attempt to take away arms and surround themselves with armies of guards? To protect themselves against the crazy people, who have no fear for their lives and usually make it through, or to protect themselves against the sane people, who hope to keep their liberty and their lives? Image how much better our country would be if politicians still had to worry about getting shot, in addition to loosing elections, every time they consider a new flaming hoop for us to jump through; they might not make the hoop. Alas, we are whipped lions. Please pity us, Great Ringmaster, and stop making new hoops.
The anti-gun advocates claim that the founders had no idea that our modern guns would ever exist, and our Constitution is outdated because of it. Nonsense. Repeating arms were already under development, and were highly desirable. Some of the founders, as members of the Continental Congress, had even appropriated money for the purchase and development of repeating arms, such as the Belton flintlock. The development of arms has been mostly funded by entrepreneurs, and adopted by armies after their introduction into the civilian marketplace. The first machine gun, the Ager gun, was purchased by none other than Abraham Lincoln after the Army ordnance department refused the proposal. The first Gatling Guns were privately purchased by General Butler for use by his men in the Civil War, and the Rough Riders used two privately purchased M1895 machine guns in the Spanish-American War. The Thompson submachine gun was invented in 1917-1918, but the prototypes were shipped just as WWI ended. It was not officially adopted by the U.S. Army until 1938, after it had been on the shelves of hardware stores for almost 20 years. The British Army rather infamously discounted the machine gun in the early days of WWI, leaving many officers to privately purchase MG and Maxim models, and many WWI pilots experimented with their own weapons. From repeating to breach loading to self-contained cartridges, very few of the advancements in arms had anything to do with hunting, and very much to do with killing, but Congress made no attempts to infringe on our rights to own them, until 1934.
The United States v. Miller decision (1939) recognized that the purpose of the Second Amendment was to fight wars, and the types of arms protected were those in "common use". The Miller case was highly flawed for one reason; Miller was dead, there were few established gun-rights advocacy groups, and so no one argued against the government. The justices had the presence of mind to recognize that military weapons were the arms protected by the Second Amendment, but because no one argued for Miller, the Court was provided no evidence that short-barrel shotguns and machine guns were already in common use. The weapons were not banned either, only licensed and outrageously taxed ($200 each transfer, about half the price of a Model-A roadster, and the same price as a Tommy Gun).
Fully automatic weapons are now the most common guns in the world, easily found in the hands of any infantryman, police officer, terrorist, or criminal. Even a squad automatic weapon, such as the M249, a light machine gun capable of firing 700 bullets per minute, from a magazine of 200, would be protected by the logic of the Miller decision. As an absolute minimum, if the civilian police can have it, the non-special civilian can have it too.
We can no more ban infantry weapons than hammers, knives, axes, chain saws, cell phones or automobiles. All of these tools have their important daily uses, even though they might be used in the occasional crime. The difference between infantry weapons and the others is that their daily use is a lot less obvious. Guns are tools, people have the right to possess the best tools for the job, the job may not be obvious or daily (hopefully never at all), but we will miss them when we need them.