Final answer:
Executive Order 9066, authorized by President Roosevelt after the Pearl Harbor attack, allowed the forced relocation and internment of approximately 120,000 Japanese Americans, citing national security despite lacking evidence of espionage. The U.S. Supreme Court upheld the order's constitutionality, institutionalizing discrimination against U.S. citizens of Japanese descent.
Step-by-step explanation:
Executive Order 9066, issued by President Franklin D. Roosevelt in 1942, was intended to grant the military authority to remove persons of Japanese descent from the West Coast. This measure was in response to the Japanese attack on Pearl Harbor, which fueled fears of espionage and sabotage among Japanese Americans. As a result, the order led to the legal internment of an estimated 120,000 people, including U.S. citizens, who were forcibly relocated to camps. Alongside Japanese Americans, around 5,000 Italian and German immigrants were also arrested due to similar concerns of national security.
Despite the lack of evidence supporting collusion or espionage by Japanese Americans, and even though many demonstrated their loyalty by serving in the U.S. military during World War II, the implementation of Executive Order 9066 resulted in a significant loss of civil rights for those of Japanese descent.
The U.S. Supreme Court, in cases such as Hirabayashi v. United States and Korematsu v. United States, upheld the constitutionality of the Executive Order, reinforcing the severe institutionalized discrimination experienced by U.S. citizens of Japanese descent during this time.