I'm the last person in the field of political science who is qualified to hold court on political theory. Like most people trained in American politics I know the relevant philosophical touchstones of the people who wrote the Constitution – Locke, Hobbes, Mill, etc – thoroughly enough to avoid embarrassing myself and to teach it effectively in the context of non-theory courses. Accordingly I do know a couple of useful things. One such nugget of knowledge is that nearly every one of the hundreds of competing definitions of terms like state and sovereignty boil down to, as Hobbes put it, a monopoly on the legitimate use of force.
That does not imply that individuals may never use force legitimately. Common law tradition back to the dawn of civilization recognizes, for example, that the individual can act in self defense when attacked. But as the state retains the right to determine whether an act of self defense is justified, even this is not a proper exception to the state monopoly. The reason that this idea is so central to the definition of a state or a legitimate, sovereign government is that if every individual or self-appointed group is able to determine for him- or herself when the use of force is justified and legitimate, then that's not a state. That's not a society. That's what Hobbes was referring to when he described the "State of Nature." Without a state monopoly on the use of force, the use of force becomes unpredictable to the individual. Whereas I can walk to work and feel reasonably confident that I will not be shot at random (note that this is not impossible, merely unlikely enough that I walk to work without a phalanx of personal bodyguards and a small arsenal of weapons to fend off highwaymen who might, in a term that almost certainly cannot be used in polite conversation anymore, Shanghai me) in a world in which everyone gets to decide when to use force without the threat of state retribution or punishment I can't do that. Like everyone else in society, as Hobbes explained so long ago, I would have to devote so much of my energy, resources, and existence to defending myself that I'd engage in no other productive activity. And despite my best efforts at self-defense, I'd learn that no man is an island when anarchy reigns and life would indeed be solitary, poor, nasty, brutish, and short.
As I posted over a year ago during the Trayvon Martin trial, this is essentially what "Stand Your Ground" laws produce. Every individual is left to decide when he or she feels threatened enough to justify using force to defend themselves from a threat (real or imagined). And if we're all making that decision on our own, using our own criteria, and without the threat of sanction (As written, the laws make prosecution nearly impossible; what prosecutor could establish that I did not fear for my life if I insist stridently enough that I did, regardless of whether that fear was justified or rational?) then we are teetering on the edge of a very dangerous precipice here. The fantasy of gun enthusiasts is that everyone will go around armed, that Good Guys are easily distinguishable from Bad Guys, and that somehow people making this decision independently according to no objective standards will use lethal force judiciously and wisely. In a nation of 320,000,000 people that seems pretty likely, right?
In Michigan this week a woman with a legally permitted concealed handgun pulled out her weapon and blazed away at someone she believed she saw shoplifting as the purported thief drove away from a Home Depot store. This woman, who was judged by the state and the few mechanisms of screening in place to be competent to walk around with a loaded gun, is not smart or rational enough to have thought what a normal person might in that situation – Maybe write down the license plate and call 911? Maybe tell a store employee and let them handle it according to their established and well rehearsed corporate policy? No, her judgment was that it was necessary to respond to what she believed was a nonviolent petty property crime by firing several rounds at a moving vehicle, the consequences of which could have been disastrous in any number of ways. And this is in a society in which the threat of sanction exists. She can be, and might be, prosecuted for her wanton and irresponsible actions. That wasn't enough to make her pause or to knock any sense into her.
The more people we arm, the more we are forced implicitly to trust that the people with guns will make just decisions about when and how to use them. Forgive me for saying that absolutely nothing about the American concealed carry gun enthusiast as a class rouses merits faith. Advocates can claim until they're blue in the face that most of them are sane and rational and Good; whether that is true is irrelevant. Ninety-five percent isn't good enough in this case, leaving tens of thousands of unstable and untrustworthy knuckleheads out there armed and ready to act out their Rambo fantasies. And in the long term it is not alarmist to ask how a society is supposed to survive when one of the defining powers of the state is privatized.