Updated

The National Archives has unveiled a handwritten note by Abraham Lincoln exhorting his generals to pursue Robert E. Lee's army after the battle of Gettysburg, underscoring one of the great missed opportunities for an early end to the Civil War.

An archives Civil War specialist discovered the July 7, 1863, note three weeks ago in a batch of military papers stored among the billions of pages of historical documents at the mammoth building on Pennsylvania Avenue.

The text of Lincoln's note has been publicly known because the general to whom Lincoln addressed it telegraphed the contents verbatim to the front lines at Gettysburg. There, the Union army's leaders failed for more than a week to aggressively pursue Lee following his defeat.

A week after Lincoln's note, the Confederate army slipped across the Potomac River into Virginia and the war continued for two more years.

Though Gen. George Meade led the Northern troops in the battle at Gettysburg that marked the turning point of the war, he has always been faulted for not closing in and destroying Lee's army.

At a news conference Thursday, archivist Trevor Plante said he was looking for something else last month when he found Lincoln's note tucked away in a drawer among other papers. His reaction was "wow" when he recognized the handwriting and Lincoln's signature.

Lincoln's note says "the rebellion will be over" if only "Gen. Meade can complete his work." Lincoln says he wants the "substantial destruction of Lee's army."

Plante's find reinforces "Lincoln's desperation to turn Gettysburg not just into victory, but decisive victory that stops the bloodshed," said historian Allen Guelzo, director of Civil War era studies at Gettysburg College.

The importance of the newly discovered document is that it is in Lincoln's own handwriting, pinning down in time what he was thinking.

The accuracy of the long-known telegram communicating Lincoln's thoughts was not in doubt. At the same time, "there are always risks" relying on documents by a third party for what Lincoln was saying or writing, said Guelzo.