"Why isn't it obvious to Americans that the same laws should apply to tourists and residents as it does to Americans, i.e. every one within or at their borders should be treated the same way?"

Every country since the beginning of the city-state has been suspicious of strangers. Ever hear of that big wall thing they have in northern China? They didn't build it to keep the cattle from straying. There's another big wall in the northern England. How about all those castles dotted across Europe?

You think people get treated the same everywhere outside the US? That's really funny...