It's a curious phenomenon. When I'm in the states, I am barely able to write. My thoughts are more diffuse, my observations less concise than when I write in Paris. I have often wondered about this. Obviously many writers write wherever they are. Not me. I find simply that when I am in the US, a place where I can so easily verbalize the ideas swirling around in my head, I am not as able to articulate them as well. In Paris, my mental process is so funneled, so intense.
When I am in Paris, I often have stories that explode from me. I wake up and have to write a passage or a paragraph or an entire essay, and can't perform any other tasks or functions until the crystallized thought is transcribed. Business and other mundane details are tended to when I have captured the wild mental beast and put it into its written form.
Now I'm back here for a short stay in the US. The obervations and thoughts are there, but more transitory and elusive. "Oh, yes, I ought to remember to write about that". The compulsion isn't there. The idea has less shape to it, the story lacks flavor.
Lord knows I am no Hemingway --- but I wonder sometimes if other expat writers have found their voice when living in Paris, or any land where the native tongue is not their own. There, thoughts are distilled through the daily filter of another language, forcing the would-be writer to hone the narrative, giving a perspective that is unavailable when back "home." When I am living my American life in my maternal language, my native culture, my thoughts are more distracted, my prose muddier.
A friend recently told me she loves to live in Paris simply because it's where "a cucumber tastes like a cucumber." It's also a place where a thought tastes more like a thought.