If you live in an insulated community where everyone is like one another, religious values and family obligation are strong, most of the people you see are proud of who and what they are, and you have been taught that the outside world is threatening and despises you, it takes an effort not only of imagination but of will to want to leave it for the possibilities of American life, and you will pay a price in alienation and guilt if you do. That's been the American immigrant experience since the first Irish Catholics got off the boat.