The NRA steadfastly maintains that the 30,000 gun-related deaths and 300,000 assaults with firearms in the United States every year are a small price to pay to guarantee freedom. As former NRA President Charlton Heston put it, "freedom isn't free."

And when gun enthusiasts talk about Constitutional liberties guaranteed by the Second Amendment, they are referring to freedom in a general sense, but they also have something more specific in mind---freedom from government oppression. They argue that the only way to keep federal authority in check is to arm individual citizens who can, if...