>On the technical side, the difficult bit is coming up with ways that discern the owner of a computer from a mere possessor of a computer. There are many legitimate cases for protecting against a mere possessor (evil maid, datacenter, theft prevention), to the point that blanket outlawing processors with built in code signing isn't going to happen.
That idea is so easy to abuse (e.g. are you sure you become the owner when you buy a computer?) that IMO there really should be no distinction between owner and possessor. If you have physical access to the device you should be able to do whatever you want with it. Physical security is easy for people to understand, unlike public-key cryptography. I'd much rather have maids steal my encrypted bits due to my carelessness if it means I have full control over my hardware.
That idea is so easy to abuse (e.g. are you sure you become the owner when you buy a computer?) that IMO there really should be no distinction between owner and possessor. If you have physical access to the device you should be able to do whatever you want with it. Physical security is easy for people to understand, unlike public-key cryptography. I'd much rather have maids steal my encrypted bits due to my carelessness if it means I have full control over my hardware.