Major realization I've just had: There's a fundamentally confusing mirror-image of concepts in trying to think about safety and security. To be a security expert is to imagine every possible enemy, and defend against all of them. But, for any of us to have any security at all, relies on the fact that not every enemy you can imagine actually exists. If you don't prepare for every possible enemy, your preparations are not enough to make you safe; But if you do prepare for every possible enemy, it still wouldn't be enough to make you safe if all those enemies actually existed at once.