If Iran is in fact attempting to develop nuclear weapons, which they very well may be, it is somewhat asinine to assume they would actually launch a NUCLEAR attack on Israel despite what they think about the place. Nations like Iran have a nuclear goal for two reasons; leverage and deterrence.
On the leverage front, the nation feels having a nuclear weapon gives them a step up on any negotiating table. When a nation is viewed as somewhat unstable or volatile, the fact they have a nuc strikes fear in other nations.
On the deterrence front, if Iran does in fact develop nuclear weapons they will have some confidence that a conventional attack on a potentially nuclear nation like Israel will likely not result in a nuclear response. Israel will most likely not defend themselves with a nuclear weapon (like we did to Japan), when they know they will get one in return.
As far as Israel's nuclear response, it is highly doubtful they have any long range nuclear capability. I believe they are only estimated to have maybe 100 warheads, and chances are they probably only have the capability to arm large bombs. This would require flight into Iranian air space and getting by Iranian air defense to attack. Hell, given their "cannot confirm nor deny" stance, they may not even have any operational nuclear weapons, but they wont say they don't because of the above reasons (leverage/deterrence).
On the leverage front, the nation feels having a nuclear weapon gives them a step up on any negotiating table. When a nation is viewed as somewhat unstable or volatile, the fact they have a nuc strikes fear in other nations.
On the deterrence front, if Iran does in fact develop nuclear weapons they will have some confidence that a conventional attack on a potentially nuclear nation like Israel will likely not result in a nuclear response. Israel will most likely not defend themselves with a nuclear weapon (like we did to Japan), when they know they will get one in return.
As far as Israel's nuclear response, it is highly doubtful they have any long range nuclear capability. I believe they are only estimated to have maybe 100 warheads, and chances are they probably only have the capability to arm large bombs. This would require flight into Iranian air space and getting by Iranian air defense to attack. Hell, given their "cannot confirm nor deny" stance, they may not even have any operational nuclear weapons, but they wont say they don't because of the above reasons (leverage/deterrence).