STRASSER: What´s your nationality? RICK: I´m a drunkyard. R ENAULT: That makes Rick a citizen of the world. (Casa blanca) Al so a way to define your nationality. If we look an a global scale, all nationalities define themselves mostly based on geography - people living in a defined area for a certain (longer) time. So I would have to answer "I´m a traveller." To bad that they don´t issue passports...