Last year on Dec. 14, a troubled 20-year-old youth shot and killed 20 children and six adults before shooting himself at Sandy Hook Elementary School in Newtown, Conn. The anniversary of this tragedy is itself a tragedy. It is the tragedy of nothing learned.

In America, where the Second Amendment of the Constitution is placed by a hard-core minority above all other rights of the people, mass shootings have unsurprisingly become regular affronts to domestic tranquility. But, coming just before the Christmas season, this massacre of the innocents made a special claim on the nation’s conscience.

If the needless deaths of children and the staff who loved them could not move Americans to pity and then action, then surely nothing would. Indeed, for a few months afterward it looked as if some meaning would rise from the meaningless slaughter. It appeared that Congress might pass controls on guns to strike a balance between gun owners and other Americans.

The Senate proceeded with a bill to expand background checks for gun purchases. Unlikely senators, such as Pennsylvania’s Republican Sen. Pat Toomey, backed the effort. But before April was done, the Senate had rejected the bill. The stale arguments and old prejudices had prevailed, as usual.

Now the Sandy Hook school has been demolished, the recordings of 911 calls have been released to bear new witness to the horror that day and, as the Post-Gazette’s Tracie Mauriello reported Sunday, residents have been trying to put their lives back together. If only America’s leaders could honor them by doing the same for the nation. Instead, the lesson goes unheeded.

First Published: December 10, 2013, 5:00 a.m.