During World War II, many Japanese-Americans were sent into internment camps thanks to Executive Order 9066.
After the attack on Pearl Harbor by the Japanese military, many members of the government and US citizens in general were paranoid that there would be another attack on America by the Japanese. To ensure that this attack did not happen, President Franklin D. Roosevelt signed Executive Order 9066. This allowed for the removal of individuals from military areas. After this, internment camps were formed for Japanese-American citizens.