Just after the Yanks celebrated their bi-centenial, we were had the "mis-fortunate" to have to spend a few months on the West Coast of the States. We visited a couple of places uneducated in the ways of Jack. Their normal opening gambit was "Gee, why are you guys here". To which our response was always " We let you try and get it right for two hundred years and as you haven't, we've come to take it back!"
Needless to say, the joke went way over their heads.