In comparison between US and Europe: US is like a melting pot. No one can claim to be the true owners because most of the people's ancestry lies in some other nation. This is not the case with Europe. And thus, you can feel American without even living there but you will never be an European even if you have lived here for more than 50 years. That probably affects everything here. UK might be a bit more accepting though. So if you can never feel like you belong there how can you realize your dreams? US and Australia: If you want a laid back life, Australia is a much better place but there is very little scope there. If you want tough competition and want to come out as a winner US is the place to be and if you want to have a nice life and don't want a rat-race, you are better off in Australia. So basically, it depends on what you want. Both US and Australia could be the place to realize your dreams but it depends on what your dream is.