I don't know if we're any worse than any other country or not but being American myself, hell ya we're rude and self centered when generalized. Everyone generalizes, it's not country specific or group specific. I just had someone in another thread generalize me while arguing against me generalizing.

Everyone has good and bad in them and depending on anyone's personal experience they'll see either the good or the bad. The rest of the world thinks Americans are rude, but look at them...Most of my friends are asian(I'm white) and as a generalization asians are racist as hell. So don't let it bother you. No one is perfect.