In the abstract, self-driving cars should make traffic in cities better. In practice, I think self-driving cars will make traffic congestion far worse, requiring a fairly substantial redesign of the road systems in American cities.
The short-term congestion and long-term time, expense and disruption of the required redesign of city roads present yet another serious challenge for any company hoping to profit from a fully autonomous vehicle future. It will markedly slow down the transition, and give cities a major lever to extract rents from any company hoping to operate unmanned vehicles on their streets.
