Before the NSA Honored Historian David Kahn, the FBI Investigated Him

Recently declassified files show that J. Edgar Hoover's FBI once investigated cryptography historian David Kahn, potentially aiming to prosecute him for gathering cryptography manuals. This revelation underscores the intense scrutiny and fear of encryption that characterized the era, highlighting how even respected scholars could be targeted. Kahn, who later became a prominent figure in the field and was honored by the NSA, faced significant risks during his career. This episode sheds light on the broader historical context of government surveillance and the tension between national security and intellectual freedom.