It isn’t often that the Supreme Court gets to dig down to Constitutional bedrock in the Bill of Rights. But yesterday, at the Court’s stately chamber, the nine took up the question of whether the Second Amendment gives individual Americans the right to keep a gun at home. The nine sat to hear, as in most great civil rights cases, the complaint of an ordinary American, in this case a retired security guard named Dick Anthony Heller, who felt the Columbia district was abridging a right guaranteed to him under our Constitution. The case could have wide impact, as there are some 192 million guns in the hands of 44 million persons in this country, according to a government sponsored survey in 1994.

In most places in this country there are few impediments to an individual keeping and bearing arms. Many states allow residents to walk into a sporting goods or other store, attest that they aren’t felons and are over the age of 21, and drive home with a pistol out in the open on the seat beside them, no license needed. That is even the norm in America. Over most of the country, the Supreme Court’s decision won’t change a whole lot in terms of gun ownership. In most places, the freedom in respect of arms that is enshrined in the Bill of Rights is taken as having been granted by the Founders of America.

In the nation’s largest metropolitan jurisdictions, however, the Supreme Court’s decision could have a huge impact. The case before the Court involves a challenge to a Washington D.C. law that bans handguns and requires rifles and shotguns to be kept disassembled or otherwise non-operable. The justices seemed to focus on the fact that those two requirements in combination left residents of the district insecure in their own homes, our Joseph Goldstein, who was in the Supreme Court yesterday, reports. America, represented by the solicitor general, sought to avoid linking the right to keep and bear arms to militias, apparently for fear the justices could end up allowing ordinary citizens to keep the kinds of weapons modern militias use, like machine guns.

New York City’s law isn’t as strict as that of the Columbia district, but it’s close. In New York City one needs a permit from the police department to keep a handgun at home. The problem is that the permitting process is entirely at the discretion of government officials. Mayor Bloomberg could instruct his police department to draw up a lawful licensing system that gives law-abiding, mentally sound adults with good vision the right to keep and bear a handgun. But Mayor Bloomberg has a hostility to this civil right that leaves little room for even those who feel they need to protect themselves in their own homes to keep and bear an arm.

We’re reluctant to predict how the Supreme — or any — court will rule, but it’s beyond us why the mayor is so exercised on this head. He speaks of “illegal” guns but rarely of the difficulty law-abiding citizens have owning legal guns. If he were balancing his campaign against “illegal” guns with a campaign to expand the rights of law-abiding citizens to own guns that are legally purchased, he would have gone a long way to defusing the issue. Most New Yorkers don’t want to own guns or carry them; they have a magnificent police force to protect them. But no one likes to see a crabbed view of the Bill of Rights, which is what Heller is about.