Re: And of course the moral issue...
"But you do have a point that all these cases have to be covered, evaluated, resolved, and catered for before a car can be autonomous"
I see this kind of statement quite a lot in the discussions of autonomous cars.
No you don't need to solve every possible case before implementing this. We don't do this for any other form of engineering. All you need to do is to solve enough of them that the autonomous systems are better than the (quite fallible) meatbags that are currently in charge of driving.
The most recent stats I can find (2016) on the current state of play in the UK show ~1800 fatalities and ~180,000 injuries on the roads. US is ~37,000 (impressive as it's only around 5X the UK population, but no doubt greater distances for emergency response, maybe more miles travelled pp etc etc of course). Oz ~1300 likewise. So, there's your target - autonomous vehicles just need to kill/injure fewer people than that.
So, all the autonomous systems need to do is to show that they're safer than these current figures. At that point, the insurance companies are going to step in and start pricing us meatbags out of our cars, to keep their own costs down.
Our friends in the Gummint may also take a hand, to cut down the overall health costs. There are already rumours of them introducing a road tax per mile travelled, in preparation for losing all that petrol tax now that they've mandated that we're all going electric Real Soon Now (another rant, don't get me started...). It would be simple to extend that as another way of pushing autonomous cars.