when a british actor does an american accent everyone’s like “i didn’t even know they were british until they were on colbert.” but when americans do a british accent everyone’s like “they’re supposed to be from east cocksford but their glottal e’s are north dicksford. shameful.”
Saw an interesting interview with Hugh Laurie talking about this (on playing House and 'getting away with' doing an American accent):
".... because they're much less interested...they don't have that 'Professor Higgins' ear for.... class and background and geography and the way the British are much more attuned to wait a second where are you from and what trick are you trying to pull on me by... with that particular choice of words. I think partly again because it's such a big country nobody really.... it doesn't bother people so much where you're from or why you sound the way you sound. America's a country that's too big to know itself. Someone living in Florida's go no idea how people behave or what they eat or how they dress in Oregon, it's just so far away - whereas we know, of course, we know absolutely everything about... every British drama we watch, we're like, well that's High Wycombe, that could never happen because it's a one way system there! whereas America's so mythically grand, it's too big to know it'self, and that actually has an affect with things like accent. "