American internment camps during World War II held Japanese-Americans who did no wrong.
Better known as the Internment of Japanese Americans it was a forced relocation of people of Japanese ancestry in concentration camps in the western interior of the country. It held between 110,00 and 120,00 people, most of whom lived in the Pacific Coast. Approximately 62% of the internees were United States citizens. These actions were taken by the president Franklin Delano Roosevelt after the Pearl Harbor´s attack.
More than the half of the Japanese american people held were Nisei or Sansei, this means second or third generation of american born japanese with U.S. citizenship. The rest were issei, first generation who had born in Japan and came to America but according to the U.S. law they were unfit to be U.S. citizens.
The internment is considered to have resulted more of racism than from any security risk posed by Japanese-Americans.
Roosevelt approved the incarceration with the Executive order 9066 on feburary 19 of 1942. This order allowed regional military commander to designate military areas from which any person could be excluded. Then the West Coast was declared as excluded from all Japanese ancestry people, This decision included all of the state of California, parts of Oregon, Washington and Arizona.
On the 1980s under the pressure of some organization the president Jimmy Carter opened an investigation to determine if the decision to put Japanese-Americans in concentration camps was justified. The commision in charge of investigate that found little evidence of Japanese disloyalty at the time and concluded that the incarceration was a product of racism. The president signed into law the Civil Liberties Act of 1988 in which the U.S. apologies for the internment and authorized a payment of $20.000 to each camp survivor.
I hope this answer help you understand a little more about the internment camps on American soil. Regards.