The "Republic" of Haven regards war and sneak attacks as the necessary prelude to conquest. Thus the Kingdom of Manticore needs allies, such as the planet Grayson. But sending Honor Harrington to carry the flag was a tactical blunder - on Grayson, women have no rank or rights.
Honor would withdraw if she could, but that would lead to attacks from Grayson's fratricidal sister planets. So, she must remain...for:
THE HONOR OF THE QUEEN