Some of the Tell Tale Signs That a Tourist Traveling Abroad Is American

Taking Personal Space Very Seriously

People in the US are used to having a lot of room, so they probably want the same thing when they go on vacation. They normally wish to keep their personal space as much as possible, even though they don't mind being nice and talking to strangers. It's smart to be sociable yet retain your distance at the same time.

This is a rather extreme example of people respecting each other's personal space, but you get the point!