Listening to Stone: The Art and Life of Isamu Noguchi by Hayden Herrera:
Leonie’s decision to go to Japan may have been prompted by California’s change in attitude toward Japanese immigrants. Americans had been pro-Japanese during the Russo-Japanese war, but Japan’s postwar expansionism in China met with American disapproval, especially in California. Already in 1905 a law prohibiting marriage between Caucasians and “negroes” or “mulattoes” had been amended to include “Mongolians.” The influx of Japanese laborers incited angry protests in some San Francisco labor unions, and the press was full of alarmist talk of the “Yellow Peril.” In 1906 the San Francisco school board ordered the children of Japanese immigrants to attend segregated schools. California farmers established the Asiatic Exclusion League and orange growers around Pasadena set up signs saying that no Japanese or Chinese would be hired. For a mother with fierce pride in her son, who wanted to protect him from the sting of racial prejudice, these changes were surely disheartening.