At first glance, many appear uninteresting. Virtually all the sets share the same generic textbook knowledge that soldiers learn to pass career development courses. These include definitions of terms, acronyms, forms to turn in, laws, procedures and radio protocols.

But in many cases, servicemen or women have added their own need-to-knows and highly specific security details.

For example, an individual at one base noted down over a 100 things to know related to their specific function. These included the location of modems that connect vaults to the monitoring facility, the procedures for duress signals for each area on base, the sight pictures of cameras aimed at the vault as well as the components and workings of their console. Details around the composition of passwords, usernames and whether they can include spaces were also detailed in the cards.

Some platforms also show when users last studied their flashcards. The user above studied these details most recently in April 2021, although it also appeared to have been removed after Bellingcat contacted NATO, the US Department of Defense and US European Command to ask for a response to the findings of this article.

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