NPR ran a story this morning, “NRA Targets One Of Its Own In Tenn. Race,” that nicely illustrates the perils of single-issue politics, although you’d never learn the principle of the matter from the NPR account. It seems that the NRA has launched a $75,000 ad campaign against state Rep. Debra Maggart, a long-time NRA member and avid gun-owner who a year ago had an “A+” rating from the NRA. Her sin? She and several other Tennessee Republican officials opposed a bill that would have allowed employees to keep guns in their cars while parked in their private employers’ parking lots.

The NRA’s Chris Cox, who’s spearheading this political vendetta and, in the process, is supporting Maggart’s tea-party backed opponent, invokes both “our First Amendment right to assemble to petition our government” and, of course, the Second Amendment, seemingly oblivious to the fact that neither is relevant here. In fact, the issue could not be simpler: individuals, including employers, have a right to determine the conditions on which others may enter their property.

The Second Amendment prevents the government, not private parties, from infringing your right to keep and bear arms. If a private party can ban you from his property for any reason, good or bad, he can do so for carrying a gun. So too with the First Amendment: it limits what governments, not private parties, may do; government may not violate your rights of assembly and petition, none of which is happening here.

As so often happens, here again we see how single-issue politics, in the name of liberty, ends up undermining liberty. The tea party should know better.