The real problem with driverless anything is the fact the USA can never string enough cable to accommodate an entire driving nation with service. So, what has to occur is what occurred in Arizona; the manufacturers preprogram the car with maps, ie: "Garmin GPS."

So, will everyone with such a car upload updates everyday? No. Will these cars perform to get a person from one point to another? Sure. But, no one knows when that computer software glitch will result in real tragedy. 

Sorry, but, there is no such thing as a secure internet and computers are not as reliable as the human mind.