Brit found this site with Soviet military acronyms:
https://www.safar-publishing.com/pos...itary-acronyms
And here's a pretty comprehensive list of US military ones:
https://www.military.com/join-armed-...-acronyms.html
And modern US military slang:
https://www.military.com/join-armed-...nd-jargon.html
These could add some realism/flavor to your campaign.
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