I've never viewed these sorts of regulative barriers as anything more than a headache for Google. There's going to be some government somewhere on earth that will be gung ho about self-driving cars. Americans will not stand for the US not being #1, so regulators will be forced to do a rather quick 180 on this.
Meh, Americans also don't like dying horribly and will freakout if they think something makes that more likely. The FDA is relatively conservative compared to many other countries and, especially after Thalidomide, most people probably appreciate that.
