How does Karen Abbott discuss themes of race in the context of the Civil War?

As Abbott profiles the four protagonists of her book, how does she use perspective to inform the reader of their thoughts and opinions?

Liar, Temptress, Soldier, Spy is narrative nonfiction. What writing and storytelling elements associated with the genre does Abbott use to tell the stories of Belle Boyd, Emma Edmonson, Rose Greenhow, and Elizabeth Van Lew? How do these elements give life to the four protagonists?