Prototypes of production vehicles have long been running on America's public roads, though in limited numbers I'm happy to say. I believe that testing of advanced vehicles should be done mostly on company proving grounds.
Now I suppose it may be necessary to do some testing of autonomous vehicles on public roads, where real-world conditions can be simulated. But let's not allow these prototypes to ignore basic safety considerations when they are out mixing with your car and mine. The idea that these unproven vehicles should be tested in public without steering wheels and brake pedals seems reckless at best.
Recently there was a report from California that occupants riding in autonomous vehicles being tested were frequently required to take over the controls for one reason or another.
That would seem to demonstrate that these vehicles are not yet ready for prime time.
Still, there seems to be a huge rush among automakers to be first with self-driving vehicles, although I'm not sure why. I do not doubt that sooner or later they'll be available to the buying public, though it could take decades.
I certainly don't know if they will be successful or not. Cost is one major consideration.
Regardless of their success or failure, plenty of testing will be needed. When they are on public roads there cannot be any wild, Wild West rules. These vehicles have lots of potential, but let's not leave a trail of killed and injured victims during the testing cycle.
If you are going to test on public roads, let us at least have a steering wheel and brake pedal. Just in case.