The problem with your theory is that it involves playing for high stakes. You are asking Israel to sit back and wait and let events take care of themselves. Well sometimes events don't take care of themselves. Sometimes revolutions are brutally crushed. Who is to say what will happen here? Who is to say the mullah's will be able to hang onto power after their country is decimated?
U.S. confirms ISIS computer expert killed in air strike (Reuters)
from the article: MI chief: Iran has enough nuclear material for bomb