Did racial prejudice play a role in the government's treatment towards Japanese Americans during World War Two? One could disagree and agree with this question.
One may argue that it was not racial prejudice because the US was attacked at Pearl Harbor and the country was extremely paranoid as during World War Two there were many spies in enemy countries. In the majority opinion it may have justified their paranoia as it says, "Approximately five thousand American citizens of Japanese ancestry refused to swear unqualified allegiance to the United States and to renounce allegiance to the Japanese Emperor." (Key Excerpts from the Dissenting Opinion, Justice Murphy.) However the fact that the US government had grouped all Japanese into the category that all of them are disloyal is a racist allegation, and weakly justifying it by excusing it as not an racial issue because the military did not have the time to evaluate each Japanese American, "it was because we could not reject the finding of the military authorities that it was impossible to bring about an immediate segregation of the disloyal from the loyal." (Key Excerpts from the Majority opinion, Justice Black.)
There is also an understanding that grouping all the Japanese Americans together is another way for America trying to maintain a white supremacy, by getting rid of non white races. Not only can the Japanese interment order be considered racist but also that it took away the rights of citizens of the United States. The United States in fact could be argued that it replicated what Nazi Germany did to discriminate against the Jewish population and justify it. Such as shutting down Jewish businesses which prevented Jewish people from having an income but also from being involved with their community, likewise the US stopped Japanese Americans from being out between eight pm and six am, "West coast military areas to remain in their residences from 8 p.m. To 6 a.m." (Key Excerpts from the Majority Opinion, 1, Justice Black). Therefore there was hardly a chance for the Japanese Americans to mingle with white Americans, creating a segregation of races through time schedules. Thus the Japanese internment order is viewed as a a racial prejudice order done to maintain white supremacy.