I remember talking to a friend one night in Paris when she remarked that all the new people she'd met in America appeared to be artificial and formal. It's been a more than a couple of years now and she might have revised her opinion. What struck me today was a passage from The Razor's edge, where Maugham confesses his incapacity to genuinely portray American characters. The reasons he gives make me believe that it was a coincidence that they appeared unnatural to one person and were beyond comprehension for the other.
I don't think one can ever really know any but one's own countrymen. For men and women are not only themselves; they are also the region in which they were born, the city apartment or the farm in which they learnt to walk, the games they played as children, the old wives tales they overheard, the food they ate, the schools they attended, the sports they followed, the poets they read and the God they believed in.
It is much easier to start writing again after a long hiatus by simply borrowing someone else' words.