law schools know that most students have no idea what their precise goals are in applying to law school. This question ferrets out those who, for example, have a PhD in Biochem and are absolutely going into patent law.
Your desire to work in other countries will work just fine for schools with strong concentrations in international law. What I would say is this: a personal statement is not a contract. You can therefore write about what your would do with your law degree, in the best of all possible worlds, if you had your druthers.
What you would do best to stay away from is: A) Vague generalities (Because the study of law will make me a better human being!) and B) Wild guesses (I think I might want to do entertainment law! Or, maybe, animal rights! Oooh, or maybe IP, because I kinda like computers and books!).
Write what is true for you, without being to syrupy, and you should be fine. Good luck!