Wiesel is a great man, but wrong in this instance. Our initial instinct is to punish Iran, but this is the wrong tactic here. When dealing with one's enemies, it is best to keep them close at hand. Keeping Iran in the UN is better than expelling them because it provides another method for monitoring them. The more we alienate them, the more evil they will brew. Just like Mordor. So no, do not expel Iran, but crush them politically.
Palestinian man suffers light wounds from rocks thrown by Jewish men in Jerusalem (Haaretz)
from the article: Elie Wiesel calls for Iran's expulsion from the United Nations