You might be surprised to know the NSA has already cloned versions of Facebook, Tumblr, and Twitter onto US classified networks so IC and DoD agents can use them to publish and exchange classified information the same way influencers use normal social media. I can't remember what they call the Tumblr clone, but the Twitter one is eChirp and the Facebook one is called Tapioca.
It's not like there's anything all that complicated about the basic tech model of "loosely synchronized, eventually consistent live data feed algorithmically sorted with the ability to follow and group sources." Where these services earn their valuations is in sheer scale of the user base combined with the backend telemetry and machine learning services that drive user profiling and personalized ads, but government institutional use would not want or need those features. As far as I know, eChirp and Tapioca are maintained by volunteers and functionally equivalent to Twitter and Facebook if you stripped out the features built for serving personalized ads and maximizing reader engagement.
It's not like there's anything all that complicated about the basic tech model of "loosely synchronized, eventually consistent live data feed algorithmically sorted with the ability to follow and group sources." Where these services earn their valuations is in sheer scale of the user base combined with the backend telemetry and machine learning services that drive user profiling and personalized ads, but government institutional use would not want or need those features. As far as I know, eChirp and Tapioca are maintained by volunteers and functionally equivalent to Twitter and Facebook if you stripped out the features built for serving personalized ads and maximizing reader engagement.