Considering the huge trade imbalance it is probably preferable to sue in the US for imports. More bang for the buck?

If you have to sue in every country where products are sold that infringe I can see where that could be awlfully expensive and time consuming. I wonder if the World Trade Commission enters into issues concerning patents? I would think so, but honestly don't know. If it were the case, then why even have re-validation in Germany? I really don't know. Does anyone know?