The number you pull out is not telling. There are billions of miles driven in the US alone and people get killed on average after 100 mil miles driven. That is where the bar is, and I can tell you, that is a high bar. Even including all the idiots, teenagers, DUI's etc. it is still one fatality on 100 mln miles. So sure, it is a tragedy that those 40.000 people die, but that is not a simple problem to fix. In fact obesity and sugar caused disease is probably a much simpler problem to solve, that could likely save way more people.