Just trying to construct the cost model for that is pretty deep. The high-altitude view is that there will be a process that slowly eliminates safety hazards.

Just trying to construct the cost model for that is pretty deep. The high-altitude view is that there will be a process that slowly eliminates safety hazards. An analogous process is lineman safety in the electric grid; at one point the probability of fatal accident for electric linemen was quite high, and it declined to next to nothing as safety procedures improved. I don't think it'll really be safe until autonomous cars have transponders and can negotiate space in real time, but then you still have all the legacy vehicles out there that don't have transponders.