In Steps to an Ecology of Mind, Gregory Bateson wrote about national character, and positioned adults and children on two axes of the Big 5 Psychological Traits.
(For example, adults might be exhibitionist and dominant while children might be spectators and submission. Okay, these aren't exactly from the Big 5, but they're pretty close.)
By looking at where the American and English national characters fell on these, he showed that interactions between individuals would result in an attempt by one to be polite appearing to force the other into a role, and this accounts for the apparent boastful (of Americans) or snooty (English) characteristics.
I'm not sure how falsifiable it is, but entertaining.