Not only were they throughout FDR’s cabinet and many cabinet offices below the Secretaries, but many of them were actively passing information to Soviet spies. Eleanor was a fellow-traveller.
Read “The Venona Secrets” for the full story. It is indeed frightening.
I have the Venona Secrets and the first time I read it, I was stunned how the press, for years, has been protecting the communists foothold in this country.