I suppose, for iran, the best way to pay back Israel for an attack would possibly not be to rain [or attempt to rain] down missiles on the country but rather to cause general upheaval throughout the region as a consequence so as to stoke anger against Israel, not only in the region, but globally - in essence Iran would play the victim to Israel's cruel, self centered aggressor so that when oil prices spiked and the already fragile global economy crashed countries already predisposed to hate Israel would, well, hate it even more. This scheme would involve shutting down the Strait of Hormuz and possibly attacking other gulf states or finding some other way to draw them into the hostilities - not to mention how Assad might try to use the chaos as cover for a major escalation against his problems.
So would such a plan by Iran be much more likely to deter Israel than a 'mere' retaliation from Hamas etc etc? Possibly. Lot of unknowns here.
[and the biggest unknown is that of Netanyahu's confidence in the trustworthiness of Obama to do the right thing viz Israel's security needs. To me this is the dynamic people tend to overlook when talking about the likelihood of an Israeli strike on Iran - of course there are strong reasons, of both a strategic and practical nature, why Israel should forbear, especially if acting alone - but if you're the decider in Israel and you've come to the conclusion that, one, a nuked up Iran is not an acceptable outcome, and two, Obama cannot be trusted, then you're between the rock and the hard place and green lighting an attack becomes very real - and when Bibi speaks what I hear is a man who has looked through the door and seen the devil - he doesn't trust Obama, and for good reason as far as I'm concerned]
