Well, yes, it is bad policy -- it hinders development of a home-grown technology and business in a field dominated by foreigners. But the direct-sale bans are based on politics, not rationality. In the long run, many Americans will be employed in a very successful domestic electric car industry, and when that happens, the politics will reverse. Then the car dealers will say, "What were we thinking?"
People may wonder why Tesla is moving part of its operation to China. I don't. It's a shame, but it's perfectly understandable.