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If you believe the optimists, self-driving cars will dominate our roads within a couple decades. This will reduce or even eliminate such human-created ills as traffic jams and fatal accidents.
I'm not so sure.
Granted, the rise of autonomous vehicles does seem imminent, with companies such as Apple, Google, Ford and General Motors already testing small fleets in realistic conditions. Some think the U.S. could have 10 million by 2020. Experts predict that the shift away from car ownership could save 1.2 million lives a year, and cut the number of cars on the road by 80 percent.