The first public revelation of Israel's nuclear capability (as opposed to development programme) came in the London-based Sunday Times on October 5, 1986, which printed information provided by Mordechai Vanunu, formerly employed at the Negev Nuclear Research Center, a facility located in the Negev desert south of Dimona. For publication of state secrets, he was sentenced to 18 years in prison for treason and espionage. Although there had been much speculation prior to Vanunu's revelations that the Dimona site was creating nuclear weapons, Vanunu's information indicated that Israel had also built thermonuclear weapons.[5]

In 1998, former Prime Minister Shimon Peres said that Israel "built a nuclear option, not in order to have a Hiroshima but an Oslo." [6]. ("Hiroshima" refers to the atomic bombing of Hiroshima, while "Oslo" refers to the Oslo Peace Accords). The "nuclear option" may refer to a nuclear weapon or to the nuclear reactor in Dimona, which Israel claims is used for scientific research. However, no scientific report from the Dimona nuclear facility has ever appeared in a peer reviewed scientific journal. Peres, in his capacity as the Director General of the Ministry of Defense in the early 1950s, was responsible for building Israel's nuclear capability.[7]

According to the Nuclear Threat Initiative, based on Vanunu's information, Israel has approximately 100-200 nuclear explosive devices and a Jericho missile delivery system. A United States Defense Intelligence Agency report (leaked and published in the book "Rumsfeld's War" by journalist Richard Scarborough in 2004) puts the number of weapons at 82. U.S. intelligence sources in the late 1990s estimated 75-130 [8]. The difference might lie in the amount of material Israel has on store versus assembled weapons.

Israel has operated three modern German-built Dolphin class submarines [9] since 1999. Various reports indicate that these submarines are equipped with American-made Harpoon missiles modified to carry small nuclear warheads [10] and/or the larger Israeli-made 'Popeye Turbo' cruise missiles, originally developed for air-to-ground strike capability [11]. On October 12, 2003, The Observer reported that the United States had equipped Israeli submarines with nuclear tipped Harpoon missiles. [12]

http://en.wikipedia.org/wiki/Israel_and_weapons_of_mass_destruction

So, I will uise the LOWER numbers from this last site, and Iran would suffer less than 3% destruction.... WHICH YOU CLAIM WOULD PREVENT THEM FROM ATTACKING ISRAEL, and acheiving their goals.