Because in Australia we're so inundated with American culture, television, this that and the other, everyone in Australia can do an American accent. It's just second nature.
I'm able to lead my life as well as make a film. My wife and my friends and people around me know that I do tend to distance myself a little bit during the making of a film, but I have to, it's a natural part of the process for me because you are indulging in the headspace of somebody else, you are investing in the psychology of somebody else and you are becoming somebody else, and so there isn't enough room for you and that somebody else.
Sometimes I'll go for something more because of the story, or more because of the director. But, generally, I have to feel like it's something that I have a real sympathy for - a person that I can completely go, "Oh, wow, oh, I'm there." Otherwise I don't feel like I will be able to pull it off at all. I know I haven't done everything very well in the past; some things have worked and some things haven't. But I need to feel like I can feel about the person, understand that person, I suppose.
English is no problem for me because I am actually English. My whole family are English; I was brought up listening to various forms of the English accent.