Why do Americans think they are the best at everything?

Yes, we don't accept foreign singers/groups (other than Led Zeppelin, Eric Clapton, Pink Floyd, Rolling Stones, The Spice Girls, AC/DC, Coldplay, the Beatles...etc). All these groups came to the US to make it big. They don't get internationally popular in Britain or where ever. That's not even mentioning actors. But you're right, we don't accept foreign celebrities. Oh, and by the way, we are the best at everything....except whining about bullcrap.