The novel Paradise of the Blind by Duong Thu Huong and the mural Man at the Crossroads by Diego Rivera both present the struggle between communism and democracy/capitalism. Let's look at both works to help you get started on this assignment.
The novel presents an allegory of the communism versus democracy/capitalism struggle. It is set in Vietnam, and its characters represent both sides of the issue. The young woman Hang, representing Vietnam itself, is caught in the middle of them and harmed by their conflicts. Hang's mother, Que, and Que's brother, Chinh, symbolize communism, while Hang's father, Ton, and his sister, Aunt Tam, symbolize capitalism/democracy. They all compete over Hang, clouding her past, making her present miserable, and seriously endangering her future. Within the novel, look for quotations, perhaps from Chinh and Aunt Tam, that support this allegory.
Now let's examine the mural. It is filled with symbolic images that represent communism (notice the red flags and the portrait of Lenin on the right side) and capitalism/democracy (look at the diversity of the people and the machines on the left side). The mural is designed to show the struggles between the two systems and the human cost those struggles bring.