Experts assert that while #Signal is technically robust, its utility for high-stakes scenarios can be limited. Government officials themselves have indicated that although Signal is suitable for unclassified discussions, they prefer more secure government-operated systems for classified communications, such as the Secret Internet Protocol Router Network ( #SIPRNet) or the Joint Worldwide Intelligence Communications System (#JWICS)

@kobilacroix granted, #Tor is used by tem alongsite their private distributed #VPN systems like #SIPRNet...

@ahriboy Case in Point: @torproject is being used by basically every government at this point and I'd say that those that don't are either criminally incompetent to setup #OpenVPN over #Tor or already have something better, like the #SIPRnet...
https://en.wikipedia.org/wiki/SIPRNet