Well, this gem. Following the link to the related post here:
They literally could not talk to each other that day. It was COMPLETELY SILOED - not just partially siloed with the command post serving as a way to make it interoperable and share communications.
@ SenRonJohnson and his team of staffers were the first to bring up the siloing of communications in his initial report released publicly on 7/21.
It appears as if unified command centers at rallies and events --(made up of Secret Service supervisors and their local law enforcement counterparts) before Butler were limited to National Special Security Events ONLY.
Those events are major federal govt or public events considered to be nationally significant and designated by the president and/or the Dept. of Homeland Security Secretary – in this case Mayorkas. They, therefore, did not include rallies and campaign events for Trump.
With this Alejandro Mayorkas also sitting on the FirstNet Board.
edit: appears as if… As far as I remember, until recently the official line was “communication was not working”.