Hastaroth, let's say you have a new dog. This dog has been treated badly by another guy in the past, so he is snapping now at everything he can get. That will leave you with two options: You can either put the dog into the cellar and lock the door. If you do that chances are quite good that he will be a little "monster-dog" once he gets out. Or you can try to "work" with the dog, which may include "speaking" to him. There is still no guarantee that he will/can change by then. But at least a chance.
EU's Mogherini in Tehran to talk nuclear deal, regional issues (Reuters)
from the article: Israel to snub foreign envoys who meet with Hamas ministers