I don't think we know it can be done - has anyone demonstrated a self-driving car that works in all conditions, but is prohibitively expensive in its current fo

I don't think we know it can be done - has anyone demonstrated a self-driving car that works in all conditions, but is prohibitively expensive in its current form? If they had, you could extrapolate and say 'it's coming as soon as the tech gets cheaper'. You can't adapt roads to fog or snow (unless you're going to enclose them in a tunnel). You can't adapt roads to pedestrians or bicycles (unless you prevent them from going near the road). Whatever adaptions you could make would be prohibitively expensive to roll out to all roads everywhere. In both the country I live in, and the USA, the government can barely afford to maintain the existing highway infrastructure. Of course it will get better, and self-driving will be more widely deployed, but I don't think you'll ever get 100% percent coverage (assuming that's what we both agree is the goal). I think in a way you're agreeing with my point - the last bit is just too hard, whether it's engineering, legal or political.