I don't believe that Israel will attack until it is known the world over that Iran has the BOMB. I base this upon the fact that President Bush used the pretense that Iraqi was developing weapons of mass destruction for going into Iraqi, and President Bush was vilified because no hard evidence was presented. If Israel were to attack without hard evidence (an underground nuclear test of an Iranian design would be proof) Israel would likewise be vilified. Additionally, Israel may use tactical atomic weapons in the attack and without real proof of Iran having the BOMB, Israel lose all world support for their existence.