Personally, I studied French for AS and can safely say that it is a huge step up. I don't know much about politics but I would say that overall it's up to personal choice. Politics goes well with English and History, but French is so so valuable to employers, simply because its another language.
If you want to do travel journalism, I would say French is a safe bet - Politics doesn't sound so relevant to me for what career path you want to take. Having done up to French AS, I can speak, read and hear French adequately and understand what they are saying. You become more fluent than you realise!