Answer:
Most likely because general Jackson respected the bravery of Barbara Frietchie.
Explanation:
Barbara Friechte is the name of a 90 year woman who defiantly hung a United States flag as her town was being invaded by forces of the Confederate States of America in September 1862. Her tale became famous thanks to a poem by John Greenleaf Whittier, first published in October 1863.
According to the poem, as Confederate troops marched through the town of Frederick, Maryland, a unit led by general Thomas "Stonewall" Jackson noticed a Union flag, hung by Barbara Frietchie. When Jackson ordered the flag to be taken down by his soldiers, Barbara stood up in defiance: "Shoot, if you must, this old gray head, But spare your country’s flag." General Jackson was so impressed by her display of bravery, that he replied: "Who touches a hair of yon gray head Dies like a dog! March on!"
While Barbara's story most likely didn't occur exactly as depicted in the poem, her tale became an enduring part of the folklore surrounding the Civil War.
