This story is an attempt to frame the social changes in China during the Mao Zedong era. It begins with the wrapping of Chang's grandmother's feet, a practice they started on her when she was only two, which stunted her growth and prohibited her from truly enjoying life. Why? Because Chang's great-grandparents were convinced that the only way to get a good husband for Yu-Fang is to physically harm her. This is a symbolic picture of what is wrong in China, from Chang's perspective.
The wrapping of the woman's feet can be contrasted to the equal and opposite problem; Chang's mother is forced to walk on her feet across China before she can be trained. This comes at a cost—Bao miscarries her first child. The question remains: What does the miscarriage signify about Chang's experience in China? It signifies that Chinese culture has continued to put strain on the women's lives who live there and want to be involved somehow in the course of Chinese history. In other words, Bao's trek is like a symbolic reminder of her own wayward relationship with Chinese policy. She is absolutely used up by Chinese society, and she is disenfranchised from power the whole time, and it comes at the cost of her family.
That's why Chang had to escape. Ultimately, even the changing tides of Chinese culture did not save her family, for in the new China, the competition between those who want capitalism and those who want Communism is so violent that Chang is made to watch her own parents being dragged into the street and publicly tortured. And when Chang escapes, she goes with the confidence that she has done the best she can to honor the painful lives of her matriarchs—by leaving, so she is not condemned to a similar life of abuse and misery.
