Gun owners had their day in court on Tuesday, when the U.S. Supreme Court heard oral arguments in the DC v. Heller case, which involves a challenge to the DC gun ban. Absent some world-shaking surprise, it is pretty clear that there are five votes on the Supreme Court to declare that the Second Amendment is an individual right. That fact alone should be enough to settle the argument over gun control and protect gun owners' rights. But as we all know, that's where the battle over the meaning of the Second Amendment begins. More to the point, Justice John...