How does Liesel connect the word communist to her past and her family? (include evidence if needed)

There is a speech going on. A man at a podium gives a violent speech condemning Jews and Communists, and Liesel suddenly makes the connection between Nazism and the fate of her family, as her father was a Communist. As the crowd goes "Heil Hitler!" and the books are set on fire, Liesel becomes nauseated and tries to escape.