New immigration blamed for rises in: crime, revolutionary terrorism, and anti-US ideas such as trade unionism. Many believed immigrants were inferior to US ideal of WASPs, and there presence, let alone interracial marriage, would have a negative impact (these marriages/relationships described as miscegenation at the time). There was a common belief in eugenics which taught of racial hierarchies w/ WASPs at the top and plentiful literature bemoaning the threat new immigrants posed to the white race.