Bigotry towards the Jews was quite common in that portion of the 20th century. Antisemitic commentary was not nearly so unacceptable as today, and a substantial proportion of Americans held antisemitic views. Belief in Jewish conspiracies was far wider than what we're familiar with today. Just as in Europe, it was particularly virulent during the 1930s. That two people who grew up during the early 20th century would harbor those prejudices is wholly unsurprising.

source: Gilman, Sander L., and Steven T. Katz, eds. Anti-semitism in times of crisis. NYU Press, 1993.

A journalistic (but cited) article about the manifestation of this in higher education might be worth a read--here's a link. I wrote about the underlying causes of antisemitism in general in a comment here.

I am (warily) approving this thread, since it is not technically against subreddit rules. It will be watched closely for racist or inappropriate discourse, bad answers, soapboxing, flame warring, and so on and so forth.