I’d go further, and predefine the available messages and bake them in - $place is {under attack|on fire|underwater|beset by the whooping palsy} etc. - and then the decentralised send no longer needs distribution of a message, just an ID and enumerated metadata, like location.

Then the men with guns come and you can earnestly say “well guys, i know you want to declare the eternal republic of Basingstoke, but all I can do is send a warning about a tornado in Slough, is that close enough?”