What does the mother's refusal to state her nationality is canadian or american signify

In the short story "Borders" by Thomas King, the mother's refusal to declare herself as either a Canadian or American signifies an opposition to imposed dominant categories. She persistently identified herself as 'Blackfoot' in order to reaffirm indigeneity and an indigenous worldview.

In the short story "Borders" by Thomas King, the mother's refusal to declare herself as either a Canadian or American signifies an opposition to imposed dominant categories. 
The conflict at the border is that Laetitia's mother will not say whether or not she is Canadian or American. Once asked regarding her citizenship, she simply says Blackfoot. This is often as a result of Laetitia's mother is incredibly happy with her folks and she looks to need them to be on an individual basis recognized in their own nation. The guards indicate their understanding by location that they might be proud if they were Blackfoot also, however they have to understand that country she is from, she there areBlackfeet on either side of the border.