Peter has a very valid point re fuel as the mission profiles tend to be very different in the USA to Europe with larger distance spreads.
This usually means that fuel considerations are more critical than the majority (not all flights) Over here.
You would expect the incidence of fuel shortage would be higher in the USA! If it is the same that would infact give the USA a better record.
But that, Pace, is the point. There are always lots of complicating factors. And demanding that we do something the FAA way just because there is no statistically significant evidence that a different way is better is not a reasonable position to take.