I routinely hear this argument -- no need to worry about the slippery slope, or about this or that Presidential candidate, or whether the Second Amendment is read as protecting the right to bear arms. Given how much Americans love guns, only a paranoid would worry about guns being banned. The only things that are really on the table, or likely to get on the table, are some modest regulations. A few thoughts in response.
1. Calls for total bans on handguns or all guns: It doesn't take a paranoid, it seems to me, to worry about gun bans when many leading politicians, news outlets, and other institutions have called for such bans. See here for a list (which is not intended to be complete). Recall also that one American jurisdiction (D.C.) does make it illegal for you to keep any gun ready for self-defense, even in your own home. (The D.C. Circuit decision striking down that ban on Second Amendment grounds hasn't yet taken effect.) Chicago and some neighboring cities ban handguns; New York, I'm told, makes handguns quite hard to get.
2. Worrying about fellow citizens' rights: It's true that the overwhelming majority of gun owners, and of gun rights supporters, live in jurisdictions in which it's unlikely that gun bans or handgun bans will be enacted any time soon. But so what? California abortion rights supporters worry about Louisiana women's access to abortions, not just about their own. You wouldn't tell them, "look, you live in California, why do you care about constitutional protection about abortion rights," because people who see something as a basic human right tend to worry about their fellow citizens' access to that right, and not just about their own. Why then assume that American gun rights supporters are purely in it for their own self-interest?
3. Looking down the road at possible future proposals: Gun rights supporters, like abortion rights supporters, free speech supporters, and supporters of other rights, also sensibly try to think ahead, not just to next year but also some decades down the line.
Take, for instance, bans on semiautomatic weapons (not fully automatic weapons or even so-called "assault weapons," but all semiautomatic weapons). Barack Obama is on the record as endorsing a total ban on "the sale or transfer of all forms of semi-automatic weapons." Now this would cover the majority of all handguns now being manufactured, as well as many rifles and quite a few shotguns. But I acknowledge that by itself it won't dramatically restrict people's ability to defend themselves, because revolvers (for handguns), bolt-action rifles, and pump-action shotguns would still be legal, and would be pretty much as effective for self-defense as semiautomatics.
Yet what would happen after this ban is enacted? To the extent the ban would have any effect on criminals, it would lead them to shift to revolvers, bolt-action rifles, and pump-action shotguns. Crime using those kinds of weapons would thus go up.
What do you expect a President Obama and others who take his view to do? Just say "Well, we were for a ban of semi-automatic weapons, and that's all we were for; though now more gun crime is being committed with non-semi-automatic weapons, we're not going to touch them"? Or would it be likelier that they'll start talking about "closing the revolver loophole," or banning "assault revolvers," or dealing with the "skyrocketing revolver crime rate"?
It doesn't take a paranoid to assume that the pro-gun-control forces would take the latter course -- and might succeed in that course, at least in many jurisdictions. It may take some years for that to happen. But people who care strongly about what they see as an important right want to preserve it not just for now, but for decades to come, not just for themselves, but also for their children.
So I wouldn't condemn those who worry about broad gun bans as paranoid, just as I wouldn't condemn those who worry about broad abortion bans as paranoid. When lots of people keep talking about banning guns, when some cities have banned handguns, and one has banned possession of any guns in a state in which they can be immediately used for self-defense, and when a leading Presidential candidate is on the record as supporting a ban on all semiautomatic guns, being worried about gun bans -- not for the whole country today, but for some of your fellow citizens today, and perhaps for many more in a few decades -- is perfectly reasonable.
Thanks to Cory Hojka for the pointer to Obama's opinion on semi-automatic weapons.