> He signaled his intent for the group to contain sensitive info by turning on disappearing messages.<p>This product reviewer has elided what "sensitive info" means. The participants are required by law (the Federal Records Act of 1950 and it's updates) to preserve records. These records may be sensitive info now, but not in 25 years, when it may be automatically declassified.<p>A product-minded engineer trying to channel Norman should know to look at all of the roles involved, including in this case the archivist.<p>> I wondered: Is Signal even appropriate for this scenario?<p>> Let’s define the scenario as: “A large group chat in which sensitive information is shared with a trusted set of collaborators”<p>Let's define the scenario as "a set of collaborators with authorized security clearance and devices", in which case we see immediately that Signal is a completely inappropriate solution.<p>> I think it’s plausible that most of the (non-techie) people in the chat didn’t realize the risk they were taking.<p>What they did was illegal (and the military action they organized was a war crime).<p>If they cared about risk, they would follow the security training they were supposed to get, instead of feeling themselves above the law.<p>> if Signal had somehow convinced the government not to use it, they would have avoided this headache.<p>"The government" here is doing a lot of work. Parts of the government said that Signal was not appropriate for top secret communications.<p>If government security training wasn't able to convince these high-level people to not use Signal, what could Signal-the-company do?<p>> it’s useful to imagine what they might do to expand into that use case<p>None of which are relevant to the actual scenario.