We know, though, that there are certain patterns and behaviors that contribute to car accidents. For example, we know that speeding was a factor in something like a third of all car deaths. And I’m pretty confident that’s an underestimate, because there are lots of roads where the speed limit almost certainly should be slower and speed would not be indicated in the accident report, even though it was a factor. (I also think it’s pretty easy to think of additional reasons speed might sometimes not be mentioned in the accident report, even when it was a factor, but I don’t have any numbers on that.)

If we regulated automobiles the same way we regulate aircraft, every single automobile would have a speed governor installed.

We also know that size is a significant factor. This is especially true anytime an accident involves a pedestrian or cyclist. And here again, despite clear, common sense evidence, cars are getting larger and heavier over time, not smaller and safer. (Cars have of course gotten safer, but mostly not through commonsense measures like, “make them smaller” or “make them go slower.” And so safety features inside the car are always fighting against our intransigence on those two fronts.)

Size and speed. This is really obvious stuff, if anybody cared.