What is an American?

     By definition, an American is "a native or citizen of the United States".

     True.

     But then, the question is why don't we ever answer "American" when people ask us our ethnicity? Caucasians whose families have been here for generations may say "white", and if you press for something more specific, chances are they might launch into, "Well, I'm part Dutch, French, Italian, British, Russian, Polish, Scandinavian, Lithuanian, Latvian, Bulgarian, Ukrainian...".

     It's not much, but I have a theory. Compared to the rest of the world, the United States is relatively young. It was fortunate enough to have been born with an adolescent rebel mindset, and not unlike a certain child born out of adultery, it is fresh and new and unbiased (well, from one perspective, anyways). At some point, it became a "melting pot", a congregation of many different types of people from around the world. When you have a newly arrived group of people, you're not going to expect them to be in unison already.
    It's the equivalent of having a certain year's tributes gathered up in The Capitol; you're not going to ask them where/what are you because it's quite obvious that they're in The Capitol and they're one of that year's tributes. Instead, you'd probably ask what district are you from, because it's the one that they can give you an answer to without an accompanying look questioning both you and your existence. From this viewpoint, it's simply logic and a tad of human etiquette.

     However, if the United States isn't an "ethnicity", then where did the other ethnicities come from? Other countries, yeah? But what's the difference between all the other countries and the US? Why are their native people automatically deemed "[Country]-an" by us and their emigrants?
    The answer, I believe, is simply time.
    The other countries in question have had time to establish their racial features and culture, while I return to the fact that the U.S. is incredibly relatively young. But doesn't this kind of mean that "American" will eventually be an ethnicity too, just like all the others? The races of the world will begin to meld here, slowly but somewhat surely, and before long (maybe a few hundred, thousand years), the ethnicity of this country will be that of all the other ethnicities in the world combined.

     Basically, my great-great-great-great-great-great-great-great(x100)-grandchildren may travel abroad someday and be presented with the question of, "So what ethnicity are you?" in some language or another, and--who knows?--they just might say, "American."