"A well-regulated militia, being necessary to the security of a free state, the right of the people to keep and bear arms, shall not be infringed."--The Second Amendment to the Constitution of the United States of America
Many people simply refer to this text, and any discussion of the regulation of firearms simply ends. I'm not going to do that, because 1) a Christian worldview demands more careful reflection; 2) there is nothing sacrosanct about the Constitution itself, that is, it isn't a religious text, or sacred object, no matter how good or correct we think it to be; and 3) we have new challenges that the Founders could not have foreseen.
One of the great strokes of genius in our founding and its documents is the separation of powers. More than this, that the Constitution does not enumerate all the rights individuals may have, but rather limits what the government may licitly do with respect to the individual. The US Constitution limits the federal government with respect to the people. In a time when participatory governance was new in the modern world, the United States articulated it fully, and most successfully. Therefore, we cannot dismiss procedural concerns in pursuit of highly desirable goals, because in our system and sensibility, correct procedure both denotes and confers legitimacy.
However, it must be said that with respect to firearms, obviously we do not live in a time when relatively small groups of citizen-soldiers could overthrow the government. It is very likely that the insurrection that gave birth to our country could never be repeated. Also, it appears to me that the highly contingent nature of political authority conceived of by the American founders owes more to John Locke and Thomas Hobbes than to the Church and to the Bible, and in that manner, could be contrary to the common good in its very conception. Of course, having been founded after the Protestant rebellion, some of that pluralism, in evidence right in the First Amendment, is not surprising. This doesn't mean that the whole project is useless, or that no rights of self-governance or self-defense exist. It does, however, mean that conceiving of the right to bear arms in this absolute, insurrectionist sense is incompatible with being Catholic. Why do I say that? Because the state has a more expansive role in the promotion of the common good than a tax revolt over 3 pennies would seem to allow, to put it somewhat crassly.
I do believe that federal regulation of firearms can only be done in furtherance of local and state objectives, in terms of legitimacy. I also believe in the judicious use of force in self-defense. Where I part ways with the "vigilance culture," if you will, is my relative estimation of how pressing a need for lethal self-defense actually is, and my assessment of the costs of exercising that right is, in terms of accidents and suicides. In my estimation, it is highly imprudent for most people to carry a firearm for personal and home defense. Most of the regulations concerning the exercise of this right under discussion seem prudent for the good of all people, with the possible exception of those involving watch lists, that have no accountability to anyone. Waiting periods and training requirements, as well as extensive background checks, seem like an acceptable circumscription of such a grave right. The people still retain the right of self-defense, should it ever arise. I don't believe that most people who choose not to use a firearm are irrationally afraid of them, or any such thing. In fact, it is the "vigilance culture" which has, in my view, taken insufficient account of how misuse and also advancing technology of firearms poses a threat to the common good.