Actually, I think state by state regulation would be a great idea, and I am not sure why people are so down on it. Sure, it’s a bit more work for developers, but they already need to handle the different vehicle codes in different cities. As long as the hardware is the same, the software can easily handle crossing borders. Now, nobody overtly wants more work, but the huge plus is the chance for jurisdictional competition and local innovation. Let the states discover the best way to regulate, don’t force them all into one mold.