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The United States, Israel, and Iran: Defusing an “Existential” Threat
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Chuck Freilich

Iran is an existential threat to Israel. This apocalyptic warning call has become a mantra continually repeated by virtually all Israeli leaders and defense officials and has been adopted by much of the U.S. national security establishment. President George W. Bush even warned that Iran’s declared intention of destroying Israel could lead to World War III.[1]

There is no doubt that Iran poses a severe threat to Israel, not only in the nuclear field, but what kind of danger does its nuclear program constitute? Is Israel’s future in imminent danger if Iran goes nuclear? The answer is probably not. Although somewhat reassuring, this response is less than satisfying.

First, the good news. It is difficult to imagine a practical scenario in which Iran would initiate the actual use of nuclear weapons against Israel. Iran has to take into account that Israel is reputed to be a nuclear power. Thus, any nuclear attack might result in a counterstrike and in a “Tel Aviv for Tehran” exchange or even a broader one. Iran certainly has a deep theological commitment to Israel’s destruction and has already proven its willingness to devote considerable resources in pursuit of this divine vision, but what price is Iran ultimately willing to pay? At what point does its cost-benefit calculus change? Would it accept thousands dead, tens of thousands? Probably. Hundreds of thousands, as it lost in the Iran-Iraq war? Maybe. Untold destruction?

Again, presumably not. As extreme as Iranian ideology is, Iran has pursued a largely “rational” policy over the years, in which its national interests have usually taken precedence over theological ones and which has generally adhered to a carefully calculated course. Iran has fundamental national security reasons, totally unrelated to Israel, for seeking a nuclear capability. Iran fears a future resurgence of Iraq, its traditional nemesis, and views the United States as the primary long-term threat to its security. It also lives in a highly unstable region in which two of its neighbors are already declared nuclear powers and many more are exploring nuclear capabilities. As aggressive as Iran’s stance toward Israel is, it genuinely fears Israel’s intentions, totally unwarranted as this may be, except in a reactive sense.

Now for the bad news. Iranian policy toward the United States and particularly Israel has been a partial exception to its generally rational strategic approach and is clearly heavily affected by nationalist and especially theological sentiment. Furthermore, Iranian rationality, at least that of the ruling mullahs, may simply be different than that of the West. When God is invoked, all bets are off. We cannot simply dismiss the possibility that the divine objective of destroying Israel is, somehow, worth the price, especially given the regime’s apocalyptic character. This is not to say that Iran is irrational when it comes to the United States and Israel, but there is certainly an element of doubt here that we cannot ignore.

An Iran emboldened by a nuclear capability will undoubtedly play a more influential, hegemonic role in the region. The unanswerable question, about which we cannot afford to be mistaken, is whether it will seek to throw its weight around and engage in potentially destructive behavior, even at the risk of devastation. As unlikely as an Iranian nuclear attack may be, there is simply no margin for error when national existence is at stake. Therefore, Israel has to take the Iranian threat deadly seriously and treat it as an existential threat, even if it most likely is not.

Furthermore, the greatest practical danger may lie not in an intentional Iranian use of nuclear weapons to destroy Israel, but in a variety of lesser scenarios. A renewed confrontation with Hezbollah seems only a matter of time, and one with Syria is quite possible. Either scenario may provide the setting for an unintended escalation that gets out of hand. Iran might threaten to use nuclear weapons to dictate the outcome of a future conflict of this sort or even as a means of affecting the Arab-Israeli peace process. Its nuclear umbrella might merely embolden Tehran to take harsher conventional measures or allow a regional ally to do so, for example, heightened terrorist or conventional missile attacks against Israel.
The danger of an Iranian transfer of nuclear weapons to Hezbollah or covert deployment of Iranian nuclear weapons in Lebanon also cannot be dismissed. Indeed, Iranian involvement in nuclear terrorism against Israel, directly or indirectly, with or without the knowledge of the Iranian leadership, may pose the greatest danger of all. The danger also exists of an Iranian nuclear capability falling into the hands of an even more extremist regime, if the current one is replaced, or of a loss of control over it in a scenario of internal chaos.

Finally, a nuclear Iran is viewed by its Sunni neighbors as a severe threat and has already led many of them, including Egypt, Jordan, some Persian Gulf states, Saudi Arabia, and Turkey, to begin pursuing “civil” nuclear programs of their own. Civil programs have this nasty tendency to morph into military ones. The prospect of a multinational nuclear Middle East is a nightmare scenario, which makes the complexity of the U.S.-Soviet confrontation pale in comparison. An Israeli-Iranian balance of terror may possibly be feasible, but what about one in which multiple adversarial actors are involved?

The Options

U.S.-Iranian Engagement

What can be done to forestall an Iranian nuclear weapon? Undersecretary of State for Political Affairs William Burns recently participated in negotiations with Iran over the nuclear issue. Others have floated the idea of establishing an interests section in Tehran. Democratic presidential nominee Barack Obama speaks of engagement as a necessity. On all sides—the United States, Europe, and Israel—the preference for a diplomatic solution is manifest.

In the past, Israel appears to have feared that a U.S.-Iranian dialogue would lead to appeasement and a slippery slope in which Israeli interests would be harmed. The European example of endless dialogue, what the European Union first termed a “critical dialogue,” then a “constructive” one, and which may ultimately become a “perpetual” one (my term), looms large. Even the change for the better in the European approach, starting around 2003, is beginning to look like more of the same: diplomats who become so infatuated with dialogue that they forget that talks must ultimately lead to a practical outcome, not become an end in themselves. Many U.S. critics of the engagement approach fully share these concerns.

Today, too, Israel’s immediate response to a U.S.-Iranian dialogue might be one of alarm, even a fear of abandonment in the face of a possible existential threat. After further reflection, however, Israeli officials might actually support such an effort, not out of belief in its efficacy, although it would be nice to be proven wrong, but as an essential way station on the route to stronger measures. Indeed, given the overwhelming importance Israel attaches to ending the Iranian nuclear threat, it would likely welcome virtually any agreement that put an end to it or at least to Iran’s uranium-enrichment program, even at the expense of its other concerns in regard to Iran (e.g., support for terrorism). The terms of reference set for such a dialogue would clearly have an important impact on Israel’s approach to the issue and confidence in its outcome.

In exchange for an end to Iran’s military nuclear program, Israel would presumably support the concept of a grand bargain, a broad set of incentives, such as rapprochement with the United States, a U.S. commitment to forgo regime change and provide security guarantees, end sanctions, and enable Iran’s integration into the world economy. Both the United States and Israel would clearly prefer an agreement that provides for complete cessation of all nuclear activity in Iran, at least of fuel cycle-related activity, although what precisely this means is a complex technical issue and they may have to accede to some limited, fully safeguarded, civil program. Israel’s only demands would likely be Iranian agreement to suspend all enrichment activity for the duration of the dialogue and establishment of clear benchmarks, with a deadline for assessing the outcome of the dialogue. Many if not most U.S. supporters of engagement favor these same conditions. Given the short timeline until Iran has the capacity to produce enough highly enriched uranium for a nuclear weapon—early 2010 and even sometime in 2009 in the current worst-case analyses—the importance of these conditions is greater than ever.[2]

Iran will probably reject the offer, as it has all others, but we will only know if the attempt is made fully, explicitly, and wholeheartedly. U.S. hard-liners on Iran in particular should support a policy of engagement. The exigencies of realpolitik are such that, if Obama wins or possibly if his opponent, John McCain, does, the United States will only be able to pursue severe measures, let alone future military action, if it proves to domestic and world opinion that it has exhausted all other options.

In any event, engagement must be conducted from a position of strength. Just as a policy of sticks with no carrots is doomed to failure, the opposite is true as well. Iran must be made to clearly understand the consequences of a failure to reach terms, and the timeline is short.


To date, Iran has shown no inclination to reach a negotiated end to its nuclear program, and Western inducements to do so have only heightened its bellicosity. Indeed, under its radical president, Mahmoud Ahmadinejad, and more importantly its supreme leader, Ali Khamenei, who is the real source of power, Iran seems to welcome gratuitous tension with the international community. Until now, however, its defiance has been cheap. Western rhetoric aside, Iran has not been called on to pay much of a price and has not been faced with the need to make difficult choices. It has truly been a case of eating one’s (yellow) cake and having it too.

Given the strategic importance Iran attaches to its nuclear program, it is highly questionable whether any combination of inducements, positive and negative, will be sufficient to engender a change in its policy. We will only know, however, if the attempt is made. Iran is a proud and ancient civilization, with a sense of its own unique place in history, affronted by the temerity of a 232-year-old “new kid on the block” attempting to dictate policy to it. Nonetheless, Iran does not want to be the subject of severe international opprobrium or an international pariah. Even the highly limited steps taken thus far by the UN Security Council generated something of an internal debate in Iran.[3]

Iran is likely to demonstrate flexibility, if at all, only in the face of imminent and severe measures. Pinprick sanctions in the Security Council will not do the trick. Iran will only get serious when the international community does.

Iran must be convinced that a failure to cut a deal will lead to truly painful sanctions, even at this time of tight oil markets. A leading oil exporter, Iran imports 40 percent of its refined gasoline products. If the West banned these sales, its economy could be brought to its knees.

Some fear that Iran could respond to such a threat by cutting off its oil exports. Oil exports make up 80 percent of Iran’s state budget. Without such funds, its economy would be devastated, and this would be tantamount to cutting off its nose to spite its face. The far-greater “stick” is thus in the hands of the West, even if the price of oil would rise again significantly.

Similarly, Iran’s domestic automotive industry is highly dependent on foreign components and could be rapidly shut down. Many other measures remain to be applied, as the United States has successfully demonstrated in recent months through pressure on international banks.

Russia is the key to sanctions in the Security Council. If Russia can be convinced to support effective sanctions, it is difficult to imagine that China will remain the odd man out among the permanent, veto-wielding members of the Security Council. For years, Russia has professed to view a nuclear Iran as a threat to its security and to oppose this eventuality. If taken as genuine, and there is no reason to doubt this, then a common basis does exist for a joint approach. Israel’s dialogue with Russia on the topic, including Prime Minister Ehud Olmert’s recent visit to Moscow, appear to have contributed to some caution on Russia’s part, but only the United States may be able to affect a change in Russia’s policy. Achieving this, however, would require a major change in the U.S. approach to issues of fundamental concern to Russia, such as NATO expansion and deployment of the anti-missile system in Europe. These may be important objectives, but it is arguable whether NATO expansion is essential at this time. Bargaining away an anti-missile system designed to prevent an Iranian attack against Europe, which is almost unimaginable to begin with, in exchange for Russian cooperation in preventing the emergence of the very threat the system is designed to foil, also appears worthy of consideration. Indeed, the “grand bargain” needed may not be just between the United States and Iran, but between the United States and Russia.

Even before recent events in Georgia and the subsequent deterioration in Western relations with Russia, the prospects of the Security Council being the source of relief were meager at best. Short of quasi-military and direct military action, the only realistic hope for a change in Iranian policy is through severe extra-UN multilateral sanctions. Here, too, the prospects are limited. To date, U.S. allies and friends, including the EU-3 (France, Germany, and the United Kingdom), have not shown much willingness to take the necessary measures. To this end, it may be necessary for the next president to make it clear that if cooperation is not forthcoming, the United States will be left with little choice but to go it alone, with all of the attendant consequences. The fear of a replay of U.S. unilateralism, such as in Iraq in 2003, may be enough finally to get the Europeans and other allies on board for serious sanctions and ultimately even a naval blockade.

Naval Blockade

Should the sanctions fail, a further ratcheting up of the pressure on Iran, short of actual military attack, could take the form of a naval blockade, preferably multilateral but unilateral if necessary. The blockade could be comprehensive from the outset or graduated (e.g., initially limited to Iranian imports of refined petroleum and then expanding over time). A partial air and ground blockade might also be feasible. Only if this, too, failed, would there be a need to consider direct military action.

Some will oppose the option of a unilateral naval blockade on the grounds that it would constitute a violation of international law and even an act of war. So be it. Illegal development of nuclear weapons also constitutes a violation of international law, as does dealing a killer blow to the international nonproliferation regime and repeatedly threatening the annihilation of a fellow member state of the United Nations. The issue is not one of niceties or international norms, but of the cold world of realpolitik. A naval blockade may be the only way of ending the Iranian threat without having to resort to direct military action.

For the economic reasons argued above, Iran would be extremely vulnerable to a blockade, and the prospects of its acquiescence to international demands are high. For the reasons argued in the next section, its military response can be expected to be quite limited. Iran talks a very good and scary game, but its behavior is far more cautious; even more importantly, its actual ability to respond significantly would most likely be very limited. Those who truly wish to deal with the problem but are wary of direct military action should give careful consideration to the blockade option.

Military Attack

In recent months, there has been extensive media speculation regarding Israeli preparations for a military strike against Iran, as well as dramatically overblown assessments of the disastrous consequences of military action, whether Israeli or U.S. Only one thing is clear: Regardless of who actually conducts a strike, Iran will hold both responsible.

The operational objectives of a military strike would be to set the Iranian program back by a few years, convince Iran that attempts to reconstitute it would result in renewed attacks and thus be futile, and make use of the time gained in order to promote an effective international regime that would make reconstitution harder, should Iran choose to do so. Preventing the program’s reconstitution would also require the capability and determination to conduct repeated attacks over the course of years and to withstand the ensuing military and political backlash. Hopefully—but no more than hopefully—a more moderate regime might emerge in the interim, whose very character would diminish the threat and which might possibly even be persuaded to dismantle the program. Of course, the opposite could occur too and may be more likely.

There is little doubt that Iran will respond to a direct attack or even a naval blockade, but its options, heated rhetoric notwithstanding, are actually limited. What can it truly do? Attack U.S. ships, block the Persian Gulf? Maybe a pinprick to make it look good at home, but beyond that, the risks of escalation and the costs to Iran’s economy are probably too great. Iran is extremist but most evidence to date indicates that it is not irrational. It may very well cause the United States greater difficulty in Iraq, a serious problem at a time when trends there have finally taken a turn for the better, and increased levels of terrorism can be expected against U.S. and Western targets. It is highly unlikely, however, that Iran would be willing to go beyond limited actions and risk direct military escalation with the United States, and it too has an interest in preserving the emerging order in Iraq. Moreover, U.S. preparations can greatly reduce, although not eliminate, the dangers of Iran’s potential responses.

Oil prices will rise, and Iran could add to the crisis by cutting output, but anything beyond temporary measures would be self-defeating. There will be a strong public reaction in the Muslim world, although Arab regimes will be quietly relieved to be free of a nuclear Iran. If the United States plays out the diplomatic route first, international reaction will be comparatively muted.

Iran is far more likely to respond against Israel, even if the attack is clearly American. Indeed, it can be expected to open up with everything it and its Hezbollah and Hamas allies have, including large-scale terrorism, rocket attacks blanketing Israel, and ballistic missiles. Israel will pay a heavy price, and there is a significant danger of confrontation with Iran, Hezbollah, Hamas, and even Syria, possibly all at once. Relations with Egypt and Jordan will suffer a serious blow. This is a price Israel should be willing to pay. Whether the price the United States will have to pay is also justified is a strategic and normative judgment call, to be weighed against the dangers of a nuclear Iran.

The real issue regarding military action is the anticipated operational outcome. Iran has dispersed and hardened its nuclear sites and may have a parallel covert program. Thus, even a fully “successful” strike would only destroy the known program; and Iran, having largely mastered the technology, might be able to reconstitute it in a comparatively short time. Clearly, U.S. operational capabilities far exceed Israel’s, especially if repeated attacks are required, but the crucial factor is time. Given Iran’s anticipated responses, as well as the fact that they would presumably be far less reticent about hiding their nuclear efforts after an attack, how long a delay in the nuclear program makes an attack worthwhile? Two to three years? No. Five or more? Probably yes.

Regime Change

Even if one believes that regime change is feasible, it will apparently happen only well after Iran has gone nuclear. To date there is little if any evidence to indicate that regime change is in the offing in the next few years, whereas a nuclear capability is highly likely. Moreover, there are no assurances that the next regime will be any better than the current one. Most of all, simply no one seems to know how to do it. The option has been roundly explored ever since 1979. Israel, in any event, would be foolish to pin its hopes on this possibility.

Living With a Nuclear Iran

Coming to terms with Iran’s emergence as a nuclear power is a further possibility, albeit one that no one in Israel wishes even to contemplate but that may become a necessity if all other measures fail. The primary options in this regard are U.S. or multilateral security guarantees for Israel or all nations in the region facing a similar threat and a change in Israel’s policy of nuclear ambiguity. The ramifications of these and other options for U.S. and Israeli policy have been analyzed in detail elsewhere but are briefly presented here.[4]

Option 1: Unilateral U.S. deterrence of Iran.
A clear U.S. declaratory policy, stating that the use or threat of use of nuclear weapons against any state in the region, or Israel specifically, would be viewed as a threat against the United States itself and would result in a devastating response. Unless Iran is irrational or a severe miscalculation is made, the combined effect of U.S. “extended” deterrence, when added to Israel’s own strategic capabilities, should provide a good response to the threat. Israel may be unwilling to suffice with a deterrent posture, however, when the price of error is existential. The possibility that otherwise “unacceptable” consequences might be tolerable for Iran’s theological and apocalyptical regime is at the heart of the problem. Moreover, in practical terms, most countries in the region, Iran included, already believe that Israel enjoys a de-facto U.S. security guarantee. It is thus not clear that a further expression of this will alter their strategic calculus.

Option 2: U.S.-Israeli defense agreements.
Extended U.S. deterrence might be further strengthened by a bilateral defense agreement, whether an overall commitment to Israel’s security or one more narrowly focused on nuclear, chemical, or biological threats. Assuming U.S. willingness to provide a formal commitment of this sort, something it has done exceedingly sparingly since the 1960s and thus a big assumption, Iran would know that it faced a contractual U.S. commitment to its “assured destruction” above and beyond Israel’s own capabilities. For reasons deeply entrenched in Israel’s national security thinking, however, it is unlikely that it would be willing to base its existence on a security guarantee, even with the United States, unless all other possible options had been exhausted.

Option 3: A multilateral guarantee, for example, with NATO.
If Israel might be hesitant to place its fate in a bilateral security agreement with the United States, it would certainly be loath to do so with a multilateral alliance, not all of whose members are very favorably disposed to it. The protracted NATO decision-making process would probably make this a moot point for Israel in any event.

Option 4: A regional security system.
This would entail a system in which the United States provides security guarantees to countries in the region. For the United States and Israel, this would have the benefit of adding a stabilizing element to the region as a whole and of alleviating Arab anger over what would otherwise be a one-sided commitment to Israel. The very breadth of the arrangement, however, is also its primary drawback. It is doubtful that many of the countries in the region would join an arrangement in which Israel was a part and that would presumably include a demand that they forgo their weapons of mass destruction programs. Israel has made it clear that it will only consider limiting its own strategic capabilities if this applies to all potential adversaries in the broader region and in the context of a regional peace settlement.

Option 5: Changes in Israel’s policy of nuclear ambiguity. It is commonly assumed that Israel is a nuclear power and that the United States is willing to accept this as long as Israel maintains its “ambiguous” status. The emergence of an Iranian nuclear capability, declared or assumed, might provide the United States and Israel with a diplomatically conducive pretext for changing their approach. Removing any lingering doubts, especially if it was thought that Israel had a guaranteed second-strike capability, would presumably add some measure of clarity and thus of deterrence. In point of fact, however, Iran must take into account that Israel is thought to already possess a nuclear arsenal and thus the added utility would appear to be marginal. Moreover, an end to Israeli ambiguity might further spur Arab nuclear development programs. The question that the United States and Israel would have to address would be whether the marginal increase in deterrent value, in itself or as part of a broader package, would justify the costs.


Sixty years after the Holocaust, Iran’s repeated threats to wipe Israel off the face of the earth are unconscionable, not just for Israel but for people of good will everywhere. To an extent, it is a moot point whether or not the Iranian nuclear capability poses an existential threat to Israel. If just one Iranian nuclear bomb hit Tel Aviv, resulting in “only” a few hundred thousand deaths, Israel as we know it would cease to exist. True, the national population today numbers close to seven million; but the economic and intellectual heart of the nation, its driving spirit, would be extinguished, national collapse would follow, the blow irreversible. One may debate the prospects of this scenario ever materializing. Indeed, this author belongs to those who believe that Iran is fundamentally rational and thus deterrable. Nevertheless, no one in a position of authority, certainly in Israel but abroad as well, has the luxury of dismissing the severity of the threat and treating it as anything less than potentially dire.

The precise timeline until the first Iranian nuclear weapon exists, as well as a more mature arsenal, is not known. Time, however, is truly of the essence, the critical factor for virtually all of the options. We may simply not have the time to play out the graduated process described in this article. As things stand today, we have something on the order of a year in the worst-case scenario, a few years at best. One way or the other, it appears increasingly likely that the moment of truth will come about during the next president’s first term, possibly early on. Very tough decisions will have to be made in Washington and Jerusalem, some of them jointly, if neither side is to be presented with highly unwanted fait accompli.
At this point, conditional but all-out engagement, limited in time and closely combined with stringent multilateral sanctions, rapidly followed by a naval blockade, appear to hold the best prospects for success at an acceptable cost, possibly even without bloodshed. Hopefully, further measures will not be required down the line. In any event, let us not engage in unwarranted, self-deterring risk aversion. Iran at least has a good appreciation of the true balance of power and for power politics. ACT

Chuck Freilich, a former deputy national security adviser in Israel, is a senior fellow at Harvard University’s John F. Kennedy School of Government and a Schusterman fellow.

Updated online November 5, 2008.


1. “[W]e got a leader in Iran who has announced that he wants to destroy Israel. So I’ve told people that if you’re interested in avoiding World War III, it seems like you ought to be interested in preventing them from have the knowledge necessary to make a nuclear weapon.” Office of the Press Secretary, The White House, “Press Conference by the President,” October 17, 2007.
2. Barak Ravid, “MI: West Won’t Halt Iran Nuke Program,” haaretz.com, October 27, 2008. Barak Ravid, “Sarkozy Views Obama Stance on Iran as ‘Utterly Immature’,” haaretz.com, October 28, 2008.
3. See, for example, Michael Jacobson, “Sanctions Against Iran: A Promising Struggle,” The Washington Quarterly, Vol. 31, No. 3 (Summer 2008), pp. 69-88. Nazila Fathi, “Debate Grows in Iran Over Nuclear Program,” The New York Times, January 23, 2007; “Iranian Press Abuzz Over Nuclear Standoff,” BBC News, September 19, 2004.
4. See Chuck Freilich, “Speaking About the Unspeakable: The U.S.-Israeli Dialogue on the Iranian Nuclear Program,” Washington Institute for Near East Policy, December 2007.