Nativism and Immigration Restriction in the Early Twentieth-Century United States

If we grant that the United States of the 1920s was a defensible social organization and that nativism could have either rational or irrational bases (see "Triumph of Nativism" PDF), why was the 1924 National Origins Act considered irrational and inconsistent with core American principles by 1965 when lawmakers overturned it? To answer this question, consider the causes and sociopolitical context of Third Wave nativism and explain the features of the 1924 immigration restriction legislation (we will not cover the Immigration Act of 1965 until later, so I do not expect you to know or write about that just yet).