They still want the local traffic to see them; this is like twitter exposing messages on your LAN to the Internet.
If you have a problem with this data being public, that's not a Twitter issue, that's a policy issue which will affect several companies (and if that's what you think, that's fine). If you think this data should be public, just not on Twitter, what sense does that make?
There aren't many analogies that have any use beyond sounding pithy. They fall over at the slightest bit of scrutiny. I don't think this LAN one is much of an exception. Data that is public by default shares little relation to traffic on my LAN. Just say what you mean. Don't want the data to be public? Sure, I think that'd be interesting to talk about. Just don't like Twitter? Also cool, though not as interesting.
Hiding this is only hiding the problem, not improving actual security.
If your military aircraft isn't in war zone, then how much do you really care about other people in the world picking up your ADS-B transmissions? After all, they can just turn the transponder off, and take on all the responsibility of dodging other aircraft.
They already have some resolution for this https://www.faa.gov/air_traffic/technology/equipadsb/privacy
ADSBExchange.com does not, I always use that as it's completely free and fully powered by volunteers. They don't do any filtering or add artificial delays. Recently they've even added MLAT reception of pre-ADSB flights (needs quite a bit of coverage in the area though!)
Asked directly they try to refuse as long as they can. However, they seem to use the block list maintained by the FFA. Sign ip now through a new convenient online form [0]. The seem to accept non-N registered, too.
ADSBexchange continues to refuse, but there's still some hope. FAA adding convenience to their process shows the pressure is rising.
Why?
And military would have encrypted insider communication between eachother
It may be naive question cuz I never operated such a thing
Then you have to rely on a human element, which is a horrible idea in a rapidly changing environment.
Imagine someone hits the base and takes out its comms. You no longer have any idea where anyone is.
And yes, there are people who have cameras pointed at the sky all over the country, and with software that says "I see a plane, and I don't see no ADS-B".
Combine https://www.tomshardware.com/how-to/raspberry-pi-airplane-tr... with https://medium.com/swlh/automated-meteor-aircraft-satellite-... and you're golden.