It depends *how* Israel attacks. If Israel really wants to play hardball, then its first attack should be a covert operation and very discreet.
Upwind of a major city, Israel should set up some vehicles that would spray large amounts of radioactive particles in an invisible cloud that would contaminate the city, then remove all trace of the vehicles. In a few days, hundreds of Iranians would go to the hospital in a panic, with radiation burns on their skin and other symptoms of radiation poisoning.
The purpose of this would be to convince the Iranian people that a horrible nuclear accident had taken place. Assuredly the Iranian government would deny this, and in turn this would create tremendous popular unrest.
It would also show the Iranian people an example of the horror that could result from a nuclear war.
Before you reel in disgust, consider the alternative of the deaths of thousands of Iranians during a conventional armed attack.
I think the decent thing to do would be to use leaflets, broadcasts, internet, international forums— skywriting— to make sure the Iranians know what’s is certainly going to be in store and urge them to do what the must to prevent it. Include some graphic pictures and some video of practice runs. And if they don’t act, give them what they asked for and give it to them in overwhelming doses. Tell them they are not the enemy, unless they choose to be the enemy. Stop apologizing and declaring them ‘innocents’ as we did with the hapless Iraqis.
Israel cannot take out the nuclear facilities without taking out the leadership of the country. Israel will use her excellent intel to do this at the dedication of the nuclear system with the leadership in attendance. That will create a window of opportunity for a CIA/Mossad jointly supported coup d’etat by the progressive, pro-western student movement. The mullahs will be rounded up and silenced. Pakistan would follow through by neutralizing the Taliban.