I agree it's a good point. A nuclear blast is extrinsic to the system. I think what something like CAP gets us to think about is failures/limitations that are _

I agree it's a good point. A nuclear blast is extrinsic to the system. I think what something like CAP gets us to think about is failures/limitations that are _intrinsic_ to the system. Someone walking around the data center and unplugging all the machines, then flying to the next data center and unplugging them, etc, would also cause all of CAP to fail. Though, thinking about it more, what it also tells us is that we need to be clear about what "the system" is. There are, after all, some systems that _do_ take nuclear blasts into account, or systems that take "physical breach by a hostile actor" into account. Less dramatically, we make trade-offs all the time as to what we consider "in" system vs "out", and it's good to be conscious and explicit about them. We see this a lot in UI, especially web UI in terms of things like what browsers to support, whether we care about users' battery life or data cap limits, if we foresee ourselves running the system in a jurisdiction with different regulations around data collection and usage, etc.