Kenji or Kenneth? Pearl Harbor and Japanese-American assimilation

Do immigrants assimilate in response to an exogenous shock in anti-immigrant sentiment? I investigate this question by examining the Pearl Harbor bombing as a natural experiment. I generate an index for the Americanization of first names from the 1900–1930 censuses and merge this index with records from the universe of Japanese-American internees during WW2. Regression discontinuity in day-of-birth estimates suggest that Japanese Americans born in the days after Pearl Harbor had more Americanized first names relative to internees born in the days before December 7th, 1941. There is no discontinuity in socioeconomic variables, and a within-family analysis yields similar results.