In his groundbreaking book The Souls of Black Folk, W. E .B. Du Bois writes, “The problem of the twentieth century is the problem of the color line” (339). Takaki introduces Part 4 with this famous quotation, highlighting the tension between American ideals of democracy and the realities of racism and inequality. As Americans entered World War II and combated Nazism and ideologies of Aryan racial superiority abroad, they were forced to reckon with their own prejudices and practices of discrimination at home—a reckoning that Takaki documents in the final chapters of his book.

Takaki opens Chapter 14 with a description of America’s entry into World War II after the Japanese bombed Pearl Harbor in 1941. The US government, unlike its treatment of German Americans and Italian Americans, singled out Japanese Americans as enemies of the state. In 1942 President Roosevelt authorized the internment of 120,000 Japanese Americans living on the West Coast. To prove their patriotism, 33,000 Japanese Americans enlisted in the US Armed Forces. Despite their military accomplishments and sacrifices, Japanese Americans faced hostility and discrimination upon their return from the warfront.

In the remainder of the chapter, Takaki details the involvement of African Americans, Chinese Americans, Mexican Americans, Native Americans, and Jewish Americans in World War II.