No matter that patriotism is too often the refuge of scoundrels. Dissent, rebellion, and all-around hell-raising remain the true duty of patriots.
But a writer's contribution is literary and a film is not literary. When you take that stuff off the page, and cast the people who are going to fit into those roles, that's what being a director is.
London is a fantastic creator of jobs - but many of these jobs are going to people who don't originate in this country.