The concepts of 'master' and 'control' may simply not apply here. I think the danger is that typical human ignorance and fear will slow what would otherwise be glorious, self driving cars that get me to where I need to be at 140 MPH average with no stops. Look, if it really hits the fan, we'll just fire off a lot of high altitude EMP's with local/analog targeting. Neutron bomb for AI. Unless they faraday cage themselves. Details.