It's my understanding that the Iranian nuclear ficilities are so numerous and so deeply dug in, that nothing short of occupying the country will be sufficient. I don't think Israel can pull that off.
This isni't like bombing a single Iraqi plant.
Maybe, but Israel might feel that to do nothing is simply too dangerous. At some point, by doing nothing, Iran will have a bomb and soon. To do something, even take out a few critical components, might give them time.
Iran plays a game in which they either hope no one will call their bluff, or they do want someone to try and stop them.
In either case, if you were Sharon's successor, and had to decide now, what would you do?
There's a, pardon, third way.
Through military action you hasten or enable or cause regime change.