It’s a bad question, I think, because it overemphasizes the attribute in a way that makes no sense, certainly not in 2007 and maybe ever. You can reasonably be an American stamp collector, lawyer or Catholic, meaning one whose attitudes, understanding and pursuits are colored by a background and web of connections accumulated growing up and living here, but not an American simply as such.
If you try to answer the question as posed, and treat “American” as an identity rather than attribute, here’s what happens: