Woops!  Got a little trigger happy, thanks for catching that...indeed it's only 10 9/11's per year.  But that's every year, pretty much like clockwork and no one seems to be like "oH MAH GAWD, the automobilses are gonna get me!"
Actually, the apologies are mine. I forgot they happen year in and year out. Excellent point. Imagine how much money, gasoline and lives would be saved by lowering speed limit to even 60. And enforcing it.

And I'll go out on a limb here. No productivity would be lost. You'd just have a better world. Or, at least, a better USA.