That's only the position in the US, I believe. In France, as long as you are more than 30 kg (children from 9 to 15) you can take aspirin.
> http://www.doctissimo.fr/medicament-ASPIRINE-UPSA.htm
I seriously doubt North American kids are facing lethal dangers while kids in France would be safe at the same age, it's not like the populations are very genetically different or something.
EDIT: Confirmed in Japan as well, you can give aspirin to children and even babies in Japan - there are no particular contraindications except prior patient history, and the discretion of the HCP. Link : http://www.info.pmda.go.jp/go/pack/3399007H1021_1_15/@Generi...
So, because FDA decides something does not mean everyone agrees with it universally.