Obviously not but that's how it STARTED. I believe Greece joined in the 70s or 80s. Originally there were only a few members, namely the ones that had been the most involved in recent wars, and their neighbours. However the idea proved useful in many different ways, hence Greece's decision to join. Nowadays of course, the EU is about much. much more than preventing France and Germany from fighting each other.
One of the really nice things about the EU is that all the parts are treated as equals even though in reality there are all sorts of economic, linguistic, religious and other differences. Nowadays kids are taught to appreciate every part of the EU for what it has to offer and whatever is good about that area. For the first time there is real hope of no more wars on the European continent.