We don't think nuclear weapons are useful,” remarked John Hamre, a former U.S. deputy defense secretary, at a symposium in Omaha, Neb., in summer 2009. “We think they are dangerous. But most countries think they are useful.”

That's an important statement to remember as the face-off continues in the Middle East between a nation that everyone knows has nuclear weapons, but does not admit it, and a nation that claims to not be developing nuclear weapons but acts as if it is. To say that Israel and Iran have their differences is a monumental understatement, but the actions of both are similar in their lack of transparency and the mixed and contradictory signals.

To some extent, these signals spring from real disagreements. In Israel, there are two opposing camps. One is led by Prime Minister Benjamin Netanyahu and Defense Minister Ehud Barak, who hold that Israel must bomb Iran's nuclear sites in the near future. The other follows former Mossad chief Meir Dagan and Yuval Diskin, director of the Israel Security Agency from 2005-11, who make the case that Israel absolutely should not bomb Iran, or at least not before the U.S. presidential election next month.

Between these camps, two polarized schools of thought emerge. The mainstream of government leaders—for the most part politically to the right—maintain that a nuclear bomb in the hands of a radical religious regime like Shiite Iran—which openly says Israel must be wiped off the map—poses an existential threat to Israel's national security. Therefore, if bombing Iran could indeed prevent that country's obtaining a nuclear capability, it is the correct strategic move.

In the government's view, the persistent claim that an attack on Iran will cause the entire Middle East to go up in flames is incorrect, because Israel's self-defense capabilities can keep Iran at bay. Israel's leaders assure their people that whoever portrays what transpires the day after the strike as a war that will cost the lives of tens of thousands of Israelis is overstating the threat. There are those who expect that the Sunni Arab world will not be sorry to see such a strike, and that the Iranian response will be measured, calculated and absorbable.

Retired air force general and former chief of military intelligence Amos Yadlin is more critical in his outlook. In his view, the decisive year to act is not 2012 but 2013, maybe even early 2014.

“We have at least a half-year left before we reach the true crossroads where we will have to make the fateful decision. But even when we reach the crossroads, in order for an Israeli strike to really prevent an Iranian nuclear bomb for a long time to come, it must enjoy legitimacy,” Yadlin says. “The international community believes there is still time for diplomacy and sanctions. Consequently, our legitimacy battery is almost empty. Above all, we must cease butting heads with the U.S. and try to reach a strategic understanding with it. Israel must shape a policy and take action to ensure that, if we are compelled to attack, the world will be behind us on the day we do so,” the general emphasizes.

Former Israel Defense Forces chief of staff Gabi Ashkenazi and current chief of staff Benny Gantz have worked hard to strengthen the military option versus Iran. Some analysts argue that even if Iran obtains nuclear weapons, it will hesitate to launch an immediate attack on Tel Aviv. Tehran has a greater and older strategic interest in treating the oil-rich Sunni Gulf States as prime targets—to be influenced by a nuclear-backed force—rather than Israel, with a known capability to retaliate.

However, hardliner government leaders still aver that a nuclear Iran is intolerable for several reasons. First, it is unclear whether Iran will be a rational player. The Jewish State may well be dealing with a culture that sanctifies death and glorifies martyrs and suicide bombers. “If we have to chose between a nuclear Iran or [act] to prevent them from having the bomb, we will take the road of action,” Yadlin contends. “You may ask why we cannot live with a nuclear Iran like the U.S. lived with a nuclear Soviet Union. The Soviet Union did not have a suicidal culture. The Iranians invented the suicide bomber.”

Also, more than in the Cold War era, the danger of unplanned and uncontrolled escalation exists between the two adversaries. There is no hotline between Tel Aviv and Tehran, so the danger of a mistaken nuclear confrontation is highly significant.

Yadlin is also convinced that nuclear proliferation will be the inevitable consequence of an Iranian breakout. “One day after the Iranians get the bomb, the Saudis will go to Pakistan,” he says. “They've already paid for the bomb. They supported the program with a lot of money. A Shiite bomb is much more of a concern in the Sunni countries—Saudi, Egypt, Iraq and Turkey. Each is a regional superpower and they will not let Iran alone posses a bomb so it will be a nuclear nightmare.”

The internal controversy creates uncertainty among allies and adversaries—and the argument about a kinetic strike tends to distract attention from Israel's other means of attacking Iran's nuclear program, which continue to generate results. Also muddying the picture is the difficulty of assessing Israel's offensive and defensive strength—which is where Israel's own concealment of its nuclear capability plays a part.

Israel has a number of Jericho missiles, with the Jericho 2 in the process of being replaced by the Jericho 3, with sufficient range to cover the entire Middle East. The missiles are road-mobile, and housed in tunnels driven into limestone hills at a base near the town of Zechariah, 28 mi. south of Tel Aviv. (The base is variously referred to as Sdot Micha and Sdot HaElla.)

It is also generally believed that Israel's four German-built Dolphin submarines constitute a second-strike force, armed with nuclear cruise missiles. Unusually, the boats feature four oversize 650-mm weapon launch tubes in addition to six standard 533-mm tubes. Three were ordered in the late 1990s and the first of three additional craft, ordered in 2006, was delivered earlier this year. Finally, Israel is also believed to have nuclear bombs that can be carried by F-16I and F-15I strike aircraft. The result is that any attack on Israel using weapons of mass destruction could prompt a nuclear reprisal against which no regional adversary has any defense.

However, the ability of Iran to launch a nuclear attack is uncertain (see p. 52). It clearly does not exist today, and a real threat will not exist until Iranian forces can launch an attack with a high probability of success. That is a simple statement, but masks a huge degree of uncertainty that is very different from Cold War concepts of deterrence.

In the Cold War, both the U.S. and Soviet Union acquired a near-guaranteed ability to inflict enormous damage on each other before the concept of deterrence was even formulated in detail. In World War II, air defenses never destroyed more than 25% of the attacking bomber force and even some of the bombers shot down had reached their targets—a catastrophic failure in the face of nuclear weapons.

In the missile era, no true defense against missile attacks was fielded because of the anticipated speed and intensity of the offensive. Multiple independently targeted re-entry vehicles, designed to overwhelm defenses, were developed and fielded before defensive systems were out of the test stage. In the West, civil defense was largely ignored after the 1960s.

In the Iran-Israel scenario, a nascent attacking force lacking countermeasures faces a missile defense system that has been under development for 25 years and that is now receiving third-generation equipment, probably including classified capabilities. Iranian uncertainty will be compounded by the potential for unconventional defensive techniques, including cyberattacks. Israel's ongoing civil defense efforts have been recently upgraded.

From the viewpoint of Iranian leaders, there can be no worse scenario than an attempted nuclear strike that fails to destroy Israel as it exists today. Israel could be seen as justified in threatening any use of its forces—including nuclear—to compel Iran to take steps to ensure that such actions would never be repeated, up to and including regime change and the surrender of existing leaders to international tribunals. Iran also could expect no support from its Sunni neighbors.

It is impossible to say when Iran would be able to guarantee an effective nuclear attack—a regional form of mutual assured destruction—if only because the equation involves Iran's confidence in its own assessment of Israel's defensive capabilities in all regimes. (That confidence cannot be at a high level, following cyberattacks and assassinations of nuclear researchers.)

The situation makes more sense in the light of other potential motivations—reasons why, to paraphrase Hamre, Iranian leadership might view nuclear weapons as useful.

Iran's conventional armed forces are weak relative not only to those of Israel, but to those of the Sunni Arab States to the south—something that is apparent to any Iranian with access to the Internet, government propaganda notwithstanding. However, by being seen as the first Islamic nation in the region to be close to acquiring nuclear weapons, Iran can appear strong.

The nuclear move has also driven the Israeli and U.S. governments to talk about military action. For governments embattled and criticized at home to magnify the threat from external enemies is not exactly unknown. At the same time, Iran's continued denials that it desires nuclear weapons allows its leaders to escape from the charge that they are warmongers.

On the other hand, a real Iranian bomb—even in the form of a handful of weapons and rudimentary delivery systems—could vastly complicate the tense military and political situation in the Gulf. At the same 2009 conference where Hamre spoke, Vice Adm. Robert Harward, then-deputy commander of U.S. Joint Forces Command, reported on a five-day Joint Operating Environment wargame held in November 2008. It reflected some probabilities: That rising nuclear powers might be willing to use tactical nuclear weapons, and that both state and non-state actors “would not view nuclear weapons as a first resort, but might not see them as a last resort.” The result: “The presence of nuclear weapons brought on operational paralysis.”

Distances from Iran to its targets are shorter in the Gulf, the Gulf nations' defenses are not as advanced as Israel's, and above all, those nations are not yet nuclear-armed. Whether they can readily use an Iranian bomb as a justification for going nuclear, without getting cut off from their Western conventional weapon supplies, is unknown.

In short, Iran's leaders can use a bomb—real or potential—to offset non-nuclear weakness, force other nations to treat their wars-by-proxy more diplomatically and generate an environment where its own people are willing to accept repression in the name of security.