He serves as an officer in the U.S. Marines, which helps pay for him to go to university and he gets into the law school at Yale, by which time you'd assume that he would have seen enough of the world outside Middletown, Ohio to be able to handle most social situations. It almost comes apart when at a dinner thrown by one of the big law firms who come to recruit at Yale he tastes sparkling water for the first time and is so unused to the taste that he spits it out in disgust.
No nation has a monopoly of insularity but one of the things about growing up in the UK is you're aware that there is a world out there bigger than the world of home. For a start there's the the other world you see every time you switch on the TV, which is usually America. You quickly learn the world is full of unfamiliar things, some of which you might encounter at some point, and you tend to be ready for them.
