One of my students told me (completely innocuously, mind you - she's 12) that I am the darkest English person she's ever met. I told her that I'm not British at all, and that I am, in fact, American. She then responded with "Well, you speak English, what's the difference?"

Apart from the obvious cultural/geographical differences, we're guilty of the exact same blanketing in the States regarding Spanish-speaking people. How many times have you heard a Dominican or Guatemalan person in the USA referred to as 'Spanish'?

I remember my high-school Spanish teacher illuminating this difference in class. It's pretty funny (and eye-opening) to be on the receiving-end of these generalizations for once.