I don’t understand under what logic AES encrypted radio communications (walkie-talkie) differ from AES encrypted radio communications (mobile network).
In the US, you can't run anything but analog voice on the bands you can use somewhat freely (CB, GMRS, FRS etc). On the amateur bands, you can run digital voice but you can't apply encoding for the purpose of obscuring the meaning of a communication.
You can do this on land mobile frequencies, but unless you're an organisation, you won't meet the eligibility requirements to be granted a licence by the FCC.
Your only other lawful option is one of the 900MHz FHSS solutions, though I don't think any of these offer robust encryption.
Well the whole point of hiding your tracks is evading law enforcement, why would you care if it’s illegal? Or is it because of the „only do one crime at a time“ thing?
I was thinking along the lines of „the state wants to oppress the protestors and makes it illegal“, but if you just want to avoid surveillance at a legal protest, yeah, you’re right.
Going into a protest with illegal communication devices is almost a direct sabotage of the protest's intent. It gives law enforcement a legitimate reason to act, even if almost certainly ex post facto. And it paints the protest as wilfully illegal--you went in intending to break the law.
"Arguing that you don't care about the right to privacy because you have nothing to hide is no different than saying you don't care about free speech because you have nothing to say." - Ed Snowden