In the poem "Barbra Frietchie" why did Jackson order his men not to hurt Barbra

Explanation:

Up from the meadows rich with corn,

Clear in the cool September morn,

The clustered spires of Frederick stand

Green-walled by the hills of Maryland.

Round about them orchards sweep,

Apple- and peach-tree fruited deep,

Fair as a garden of the Lord

To the eyes of the famished rebel horde,

On that pleasant morn of the early fall

When Lee marched over the mountain wall,—

Over the mountains winding down,

Horse and foot, into Frederick town.

Forty flags with their silver stars,

Forty flags with their crimson bars,

Flapped in the morning wind: the sun

Of noon looked down, and saw not one.