I would answer as follows: Israel has never admitted having nuclear weapons and in truth nobody really knows although yes there are strong suspicions. As a result, Israel has never threatened anybody ever with using nuclear weapons. In short, Israel isn't a smoking gun at all. Iran on the other hand has gone public calling for the removal of Israel from the planet. Don't you see a difference?
2 Yemeni Red Cross workers killed by gunmen (AP)
from the article: Israel's UN ambassador slams Qatar, praises U.S. envoy Bolton