To Israel, Iran is "rational & dangerous"

"...  In fact, the probability of this happening is quite low. Rather, the more immediate danger of a nuclear Iran lies in the extreme rationality that it is most likely to display in its actions vis-a-vis the region.... The real danger of a nuclear Iran is that this state will continue to act as rationally as it has since the current nuclear crisis began - in this case, using its image as a nuclear state as a cover to enhance its regional hegemonic goals, and advance its revisionist approach to the Middle East.

Consider how Iran has played the game of moving toward a nuclear bomb over the past decade. If there's one lesson that can be gleaned from observing Iran's behavior on the nuclear front in this period, it is that it has proceeded very carefully. While many may perceive Tehran as a rash and reckless regime rushing toward its goal of a military nuclear capability, closer scrutiny reveals a different picture. One can easily identify a pattern whereby Iran tests the international waters after almost every step it takes. Indeed, it has until now employed a simple cost-benefit analysis as its guide: moving forward on its nuclear program at maximum speed, but with minimal cost to itself - in economic, and certainly military, terms. ... ... Tehran concluded that it could endure a measure of economic hardship as a result of the suspicions that its activities aroused, it has been much more cautious about the prospect of being attacked militarily. Iran, however, has gradually been reassured that the risk of such action is minimal. In good part due to statements by high-level U.S. officials openly rejecting the military option for fear of the dire consequences of opening an additional front, Iran has come to discount the threat, even as both the United States and Israel repeat the familiar refrain that all options remain on the table.

There is little reason to believe that once it has achieved nuclear status, the current regime in Iran will be any less rational in its cost-benefit analysis, or any less averse to the prospect of being a target of military force than it was while en route to the bomb.

But the point is that Iran doesn't need to attack with nuclear weapons in order to enhance and entrench its regional prominence and hegemony...  The real danger of Iran thus lies in its cold rationality. It will no doubt pose severe challenges to the region and the world, but will be very careful that no one action, by itself, will be blatant or outrageous enough to elicit a military response. Moreover, assuming it does not act in a truly extreme manner, it will most likely enjoy enhanced immunity to counterattack for most of the actions it takes, exploiting the fact that all states will be even more wary than before of attacking Iran - once it is a nuclear state."