My experience of American drivers is fairly limited, but on the whole they seemed to be a lot more laid-back over there. The exception being in Massachusetts, where everyone seems to drive like an idiot for some reason. According to friends of mine who live there, people in other states refer to them as 'Mass Holes' due to their levels of driving prowess.
Coming from England I found their appalling driving to be perfectly normal! (Recent surveys have shown that we have the rudest and most aggressive drivers in Europe.)
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