"A well regulated Militia, being necessary to the security of a free State, the right of the people to keep and bear Arms shall not be infringed."

That's what the U.S. Constitution's Second Amendment says. Last week the Supreme Court agreed to decide what it means. It could be the most far-reaching decision on guns in almost 70 years.

That's when the high court rejected the notion of an individual right to possess guns for purposes unrelated to state militias. That 1939 decision allowed room for the federal government, the states and the District of Columbia to regulate and restrict gun ownership, and that has frustrated gun-rights advocates ever since. The case the court agreed to hear next March challenges D.C.'s 31-year-old handgun ban.

The Supreme Court shouldn't reverse this settled law.

A ruling that establishes a precedent for an individual's constitutional right to possess guns would open the floodgates and drown the courts in challenges of the existing, rational restrictions on gun ownership. And a sweeping decision could mean that the nation would soon be awash in ever more firearms.

With an estimated 192 million privately owned guns already in the country, that we don't need.