>I can't even imagine the overhead of unpacking and then "scanning" each of those letters by hand At this point in the war, all mail (not just those to service

>I can't even imagine the overhead of unpacking and then "scanning" each of those letters by hand At this point in the war, all mail (not just those to service members) entering and exiting the United States were opened by hand and microfilmed for censorship and counter-espionage purposes by the Office of Censorship[0]. So technically the mail opening and scanning aren't extra overheads, since those same steps apply to regular snail mail as well. [0] https://en.wikipedia.org/wiki/Office_of_Censorship https://en.wikipedia.org/wiki/Office_of_Censorship