A recent facebook post pointed me at an entertaining video
in favor of gun control. The point of the video, surely correct, is that mass shootings were a lot less practical with 18th century firearms than with modern firearms. Its conclusion: "Guns have changed. Shouldn't our gun laws?"
There are two problems with the argument. The first is that gun laws have changed quite a lot over the past two hundred plus years. The second is that, while mass shootings get a lot of publicity, they represent only a tiny fraction of all killings.
There is, I think, a better argument to be made for the effect of technological change on the argument for the right to bear arms. As I interpret the Second Amendment, it was intended as a solution to a problem that worried eighteenth century political thinkers, the problem of the professional army. As had been demonstrated in the previous century, a professional army could beat an army of amateurs. As was also demonstrated, a professional army could seize power. Oliver Cromwell and the New Model Army won the first English Civil War for parliament and then won the second English Civil War for itself, with the result that Cromwell spent the rest of his life as the military dictator of England.
The Second Amendment, as I interpret it, was intended to solve that problem by combining a small professional army with an enormous amateur militia. In time of war, the size of the militia would make up for its limited competence. In time of peace, if the military tried to seize power or if the government supported by the military became too oppressive, the professionals would be outnumbered a thousand to one by the amateurs. It was an ingenious kludge.
It depended, however, on a world where the weapons possessed by ordinary people for their own purposes, mostly hunting, were as effective as the weapons possessed by the military. We are no longer in such a world. The gap between military weapons and civilian weapons is very much larger now than then. One result is that the disorganized militia, the population in general, no longer plays any role in military defense. Another is that, if there ever was a military coup in the U.S., ordinary civilians would be much less able to oppose it with force than they would have been two hundred years ago.
Civil conflict in a modern developed society is much more likely to be carried on with information than with guns—a government that wants to oppress its population does it by controlling what people say and know. It follows, in my view, that the modern equivalent of the Second Amendment, the legal rule needed to make it possible for the population to resist the government, has nothing to do with firearms. The 21st century version would be a rule forbidding government regulation of encryption. A government that has no way of knowing what who is saying to whom lacks the most powerful weapons for winning an information war.
There remains a strong argument for the right to bear arms, different from but related to its original function. People who are unable to protect themselves are dependent for protection on the police. The more dependent people are on the police, the more willing they are to tolerate, even support, increased police power. Hence disarming the population makes possible increased levels of government power and the misuse thereof, although for a somewhat different reason than in the 18th century.
Which is an argument against restrictions on the private ownership of firearms.