.jpg)
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Mitsui was a physics major and had joined the club to get practice working with the technical side of the DBS. He took a class on the subject with Professor Willis Rayton, and in his own words was appreciated by the other members of the organization for his work installing a new transmitter. But that didn't matter in wartime. Mitsui was Japanese and came from a prominent Japanese zaibatsu family. Working in radio—which was especially susceptible to espionage and tampering—was not allowed.
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Mitsui, who was the target of race-based judgements himself, was forced to apologize for pursuing extracurricular interests. He wrote, “I should have been wise enough to keep myself out of DBS; in fact I have always been conscious of the fact that I was taking a rather heavy risk.” Other Dartmouth students could easily work in radio; for him, because of his race and nationality, it was a risk.
Mitsui expressed his desire to work with the DBS in an unofficial capacity. “It may not be helped,” he wrote, “if they come to me for advices and assistance on technical matters.” DBS clearly meant something to him: “I have been getting acquainted with some of the nicest fellows there at DBS, and it has been a very good practical experience for me to work with them. I have seen the most interesting part of the growth of this young and promising organization, in fact, I have had my own little share of it.” He didn't want to leave, but his own respect for President Hopkins, the College, and DBS led him to give up a passion.
President Hopkins was sympathetic to Mitsui, and certainly didn't suspect him of nefarious motives. He was sure that Mitsui had “not intended to do anything that would in any way be detrimental to the College or that would lead to misjudgement of the relationship between the College and yourself.” College leadership supported Mitsui throughout his time in Hanover. They helped him deal with immigration authorities and provided him with funds while he was cut off from his family in Japan.
Still, public sentiment and government suspicion broke through Hopkins's trust. Hopkins wrote that it was “very wise that [Mitsui] should have decided to withdraw from the organization of DBS.” Hanover was the homefront, and as a training site Dartmouth was effectively a place of war. Mitsui faced relentless suspicion, both from federal authorities and the students and community members whom he called neighbors.
Mitsui's exclusion from the Dartmouth Broadcasting System is a reminder that racist and xenophobic suspicion during the Second World War extended beyond obvious sources. He wasn't allowed to participate in a student club, despite there being no evidence of any wrongdoing. For Mitsui, participation in an innocent hobby turned into a perceived threat to national security.
To read these correspondences from Mitsui and Hopkins, request DP-11 Box 7046, Folder 17.
Posted for Dalton Swenson '26, recipient of a Historical Accountability Student Research Fellowship for the 2025 winter term. The Historical Accountability Student Research Program provides funding for Dartmouth students to conduct research with primary sources on a topic related to issues of inclusivity and diversity in the college's past. For more information, visit the program's website.