Track Coach, While I do agree that americans do have very diverse cultures in the big cities, I cannot agree with you on getting to know other cultures within the US.
You cannot expect to know the chinese culture from going to the local Fook Mii place and visiting NYC's chinatown. Same goes for Creole, other asian, european, african, arabic cultures etc.
People from these places have a completely different approach to personal relationships, hospitality, physical contact, gender differences, entertainment, time, organisation, company organisation, public nudity or what not.
Plus: Even if the communities are large enough to give an insight into their culture, they live a separate lifestyle which white americans get to see only seldomly.
You also do not get to see much architectural diversity in the US simply due to the fact that it did not exist (architecturally) until 400 years ago. So while places like Chicago< NYC Or Washington do offer some great modern architecture i have to say this: if you want to see where the world as we see it today came from, you have to leave the states.
Furthermore: while you may have been fortunate enough to know the US and other countries quite well, thjere are many americans who have not travelled further away from their home town than a few hundred miles. I personally know quite a few that never went north of NC or west of New Orleans.
Similar things you can observe in the midwest. So these people don't even care about their OWN country, why the hell would they care about any other?
It might just be about the media opening their eyes to the world out there, so if that happens, we may see a change of mind... but I believe that will be a VERY long shot.