Alexandria, Va.

For decades the Second Amendment might as well have been called the Second-Class Amendment. The U.S. Supreme Court spent the late 20th century expansively interpreting the First, Fourth, Fifth, Sixth and Eighth amendments, not to mention unenumerated rights ranging from travel to sexual privacy. But not until last month did the court hold that the Second Amendment means what it says: that "the right of the people to keep and bear arms, shall not be infringed."

What...