If you read the stupid racist comments (and I don't recommend it - Youtube comments are the dregs of the Internet) there is this one which made me laugh:
California Nevada Arizona New Mexico and Texas are the United States of Mexico. Didn't you know?
I mean they meant it as a joke - but those states used to be part of Mexico. Then the US had a little imperialistic war of aggression, and we stole it from them. Doesn't anyone know that?