Apologies for being late to this gleefest about, let's say, the signal point of error, but I've been delighting in seeing ElReg commenteers use expressions like "the Turd Reich" and "Almighty Radiant Super Excellent Holy Orange Loony Emperor". But to the point, I found this amusing:

Top Trump officials text classified Yemen airstrike plans to journo in Signal SNAFU

Massive OPSEC fail from the side who brought you 'lock her up'

[ ... ]

Signal co-founder Moxie Marlinspike couldn't hide his glee.

"There are so many great reasons to be on Signal," he opined. "Now including the opportunity for the vice president of the United States of America to randomly add you to a group chat for coordination of sensitive military operations. Don’t sleep on this opportunity ..."

[ ... ]

To the technical aspects of this: Signal is a damn good covert-comms program; it's used by Bruce Schneier, who literally wrote the book on cryptography. But:

* Hardened comms software requires a hardened OS on hardened hardware for full protection, to protect the end points. The OS and hardware of the average commercial cellphone tend to have the "get it to work" nature; breaking into them is a very profitable business model.

* Using secure comms kit securely requires a professional mindset. (*ahem*)

However, the sort of secure comms made officially available to POTUS and crew has one major and overwhelming disadvantage: Anything said over it leaves a permanent record.