In my travels I have found we are only second to the Brits on the perceived rudeness of our nationality. I grew up w/ a home in Singapore as well as the states and have traveled extensively most of my life. I have found that being a well behaved, respectful American abroad was a refreshing surprise to the locals and was always treated very kindly in return ...
err wait a sec, there was that time a local girls dad tried to run me over w/ his FIAT in the Azores, but that's a whole other story that involves my kindness, not my rudeness