Interestingly, the chance of the average American dying in in a meteor or asteroid impact is about the same as the chance of an average American dying in an airliner crash. (Sounds ridiculous, but think about it carefully.)
The problem with "us" is that "us" hasn't been around for very long. And a lot of life forms before "us" weren't around after large impacts.
Yup. And there's really nothing we can do about it. So, again, why worry?
I've never heard of a single American ever dying from a meteor impact but I do remember several airline crashes. Obviously a large enough meteor strike would kill all Americans but for the average person at any single point in time, the odds aren't equivelant. This is one of those ridiculous stats that has no empirical basis.