I (US citizen living in Japan for most of a decade) took my wife (only in the US once as an elementary school student and only Honolulu) to DC for the first time a couple of months ago. I was pleasantly surprised. I had ridden DC's subways once or twice on trips there. We were table to do everything we wanted on foot, by bus, and by train. Getting on the train from Dulles, though, we had some only-partly-clothed woman passed out with what I can only assume was a trail of partly-dried piss on the floor by her. Police took her off when we got into the city at some point, but it was a less-than-stellar start. That said, I've seen people puke and piss on trains in Tokyo as well.