Talk politics.

Americans are particularly regionalistic without always wanting to fess up to it. I have never met an Italian national who is not honest about the deep divisions between northern and southern Italy in heritage, cuisine and attitude, but I have had American students get into actually angry arguments about whether or not it is "soda" or "pop" and then question the idea that America is hard to define as a unified culture within five minutes. We are strangely convinced that everyone else is every other region is a weirdo but simultaneously convinced we are all one.