Isolationism is ok but what do we do when we are concentrating on our own issues and some insane person or group takes over a country like Russia for instance and pushes the button? It would be a good idea to take care of our own but we just can't ignore the rest of the world either. Isn't that how world wars started in the past?

As for being a bully, if we had truly been a bully we would own all the countries we defeated in wars instead of giving it back to the people. Maybe we would be better off if we owned Japan now instead of building it up and giving it back.