Possible Clues:

• American woman's declaration may be two-edged
• An American woman's promise is a dangerous thing
• Brothers promise to carry occasionally handy weapon
• Weapon from part of Norfolk with message on base
• That woman has a word for it that's cutting.
• Promise to support part of Norfolk, given means of attack
• Weapon in East Anglian dialect
• American woman's promise to provide cutter
• American women honour old weapon
• American woman's talk is a cutting thing