JaeThe State Department began including sex markers on passports in 1977, a change government officials attributed to the rise of unisex fashion and hair styles.
https://www.nytimes.com/2025/02/07/us/transgender-americans-lawsuit-trump-passports.html
“Gender-bending fashion made it harder for border officials to identify someone as male or female,” said Craig Robertson, a professor of communication studies at Northeastern University who wrote a book about the history of the American passport. “I sometimes joke David Bowie caused M/F sex markers to be added to the passport.”
Eric LawtonWhy do border officials need to identify people someone as male or female?
Mre. Dartigen [maker mode]@EricLawton @me Exactly. There's a photo right there if they need to know what someone looks like, and that's way more useful than a gender marker.