I don't know how helpful it is to use the word resilient at all if we're talking about catastrophies like this. I mean, the International Space Station is pretty resilient, but if the population of earth is wiped out in a super volcano, it doesn't matter anymore, right? I'd still call the ISS resilient though.

> So if every country passes something like EARN IT, Signal shuts down, how is that resilient?

That's not a forgone conclusion. Maybe it is for Signal, but not for chat overall. There's this thing called Tor. If you're careful, you can remain anonymous. And there's the new onion routing network Loki, which backs the Session chat app.

If things got bad enough, there are more robust options. I can imagine a botnet that spread much like WannaCry, and which offered deniable messaging via covert channels. Data transmissions would be hard to detect, and running the network components would be deniable.

When should applications should fail-open when forced to pick between availability and security?

The obvious answer is decentralization, and Signal is not equipped at all to do this.