Impending War with Iran: Israel’s Lawful Opportunity to Prevent Iranian Nuclear Weapons

by Prof. Louise Rene Beres

Abstract: Israel’s “no choice” Gaza War has been fought primarily against sub-state terrorist adversary Hamas. In the coming weeks, however, a threatened “retaliation” from Iran for Israel’s recent self-defense killing of a senior Iranian commander in Damascus could spark an active war between the two states. Ordinarily, it would be in each adversary’s interest to avoid such a war altogether, but in the particular case at hand, direct military engagement could prove gainful for Israel. Because Israel must do whatever possible to prevent its openly-genocidal enemy in Tehran from becoming nuclear, a war of vengeance initiated by Iran could offer Israel a law-based and time-urgent opportunity for “anticipatory self-defense.” Though such an argument could first appear provocative or “war mongering,” it would more likely turn out to be life-saving. With this clarifying background in mind, the following article by Louis René Beres, Emeritus Professor of International Law at Purdue University, examines the lawfulness and rationality of a now-impending war with Iran. To be sure, the tangible human and material costs to Israel would still be very high, but fighting against a pre-nuclear and terror-sponsoring state that had commenced the aggression could represent Israel’s best remaining chance to avoid an eventual nuclear war. Tehran’s mid-April promise that its declared strike against Israel would be intentionally limited “to avoid escalations” was disingenuous on its face. Prima facie, during any crisis search for “escalation dominance” by an already-nuclear Israel and a not-yet-nuclear Iran, competitive risk-taking would favor the former.

“The safety of the people shall be the highest law.”-Cicero, The Laws

Background of an Impending War: Israel, Iran and the “State of Nature”

Israel’s concerns about Iranian nuclear weapons did not arise ex nihilo, out of nothing. The precise way in which Jerusalem decides to handle such grave concerns will depend in significant measure on intersecting elements of background. In essence, by acknowledging critical connections between strategic decision-making and global authority structures, Jerusalem could best prepare itself to examine the existential problem of an “Iranian bomb” from both jurisprudential and military standpoints.

               To begin, current world politics remain in a “state of nature.” This means the “everyone-for-himself” condition that earlier political philosophers had called a “state of war.” By definition, within any such continuous context of anarchy – a bellum omnium contra omnes, or “war of all against all” – international law must ultimately operate in “vigilante” forms. In legal terms, this “Westphalian” dynamic describes a refractory “self-help” system of national security and power management.

                This bewildering system remains dense and unpredictable. Always, there will be assorted caveats and nuances to be considered by capable analysts and defense planners. Though codified legal norms don’t usually allow states to strike first in self-protection, the law of nations does permit certain residual acts of “anticipatory self-defense” under customary international norms.[vi]

               Under such binding law, defensive first strikes or acts of “preemption” could be considered permissible in variously security-threatening circumstances. But even if such resorts to anticipatory self-defense could occasionally be deemed lawful or law-enforcing, they could still prove unreasonably dangerous, strategically misconceived, tangibly ineffectual and/or manifestly irrational. It follows, among other things, that Israel should evaluate all anticipatory self-defense options along two discrete but overlapping standards of evaluation: law and strategy.

               Subsidiary questions would need to be raised. What are the implications of such considerations for Israel, an already-nuclear state increasingly imperiled by a rapidly nuclearizing Iran? Before Israel could decide rationally to invoke a calculated strategy of preemption vis-a-vis Iran, it’s pertinent policy makers and strategists would first need to assess this strategy according to the two above identified standards of evaluation.

                What does this mean for tangible security decision-making in Jerusalem? At some point, Israel could reason that a considered preemptive strike against selected Iranian hard targets (i.e., extant weapons and nuclear weapon-system infrastructures) would be convincingly legal, but would still not “work.” Alternatively, Jerusalem could conclude that any such considered strike would be promising or gainful in operational terms, but simultaneously be more-or-less illegal.

               What then?

               There would be more interrelated questions. One evident danger of waiting too long is that Tehran could more easily implement protective measures that would pose additional hazards for Israel. Designed to guard against an Israeli preemption, such measures could involve the attachment of “hair trigger” launch mechanisms to Iranian nuclear weapon systems and/or the adoption of “launch on warning” policies, possibly coupled with variously dissembling pre-delegations of nuclear launch authority. But if Iran should commence its warned “retaliation” against Israel for Jerusalem’s earlier targeting of an Iranian terrorist leader in Damascus, the resultant war could slow down or eliminate Tehran’s pertinent protective measures. In this scenario, any Iranian escalation to inter-state warfare in retaliation for an Israeli counter-terrorism assassination would be manifestly disproportionate and prima facie illegal.

What Would Constitute a Lawful Preemption?

               Optimally, Israel would do everything possible to prevent such destabilizing Iranian measures, especially because of the corollary risks of accidental or unauthorized attacks against its armaments and/or populations. Nonetheless, if such measures were to become a fait accompli, Jerusalem could still calculate correctly that a preemptive strike would be both lawful and necessary. This very consequential judgment would owe to the following plausible reasoning: The expected Iranian retaliation, however damaging, would still be more tolerable than the expected consequences of Iranian first-strikes.

               In its present jurisprudential form, Israel, which “began” in 1948, will last only as long as its leaders remain attentive to Cicero’s primal warning about national “safety.” Such core attentiveness could be entirely consistent with the authoritative expectations of codified and customary international law. True law is never a suicide pact. Israel’s basic security problems with Arab states and Iran could sometime compel Jerusalem to decide between waiting for its enemies to strike first or striking first itself.  At some point, when judged from a strategic and tactical perspective, the choice of a preemption option could appear conspicuously rational and cost-effective.

               From the standpoint of international law, preemption could also represent a fully permissible option.  In this connection, though subject to important constraints and conditions, the right of “anticipatory self-defense” is already well established under international law. And while a “bolt from the blue” Israeli preemption against Iran could involve assorted difficulties of national security policy justification, such prospective difficulties are unlikely to arise in an already ongoing conventional war.

An Israeli Decision to Preempt

               What does the ascertainable convergence of strategic and jurisprudential assessments of preemption say about Israel’s plausible calculations on striking first?  It suggests, among other things, that Israel need not be deterred from undertaking security-maximizing forms of preemption out of fear that its actions would be described as criminal. Although a substantial number of states would condemn Israel for “aggression” under any circumstances, this particular charge – so long as Israel’s preemptive strikes met the expectations of jus ad bellum (justice of war) and jus in bello (justice in war) – could be countered authoritatively by informed references to the law of nations.

               In jurisprudence, as in certain other realms, history deserves evident pride of place, The right of self defense by forestalling an attack appears in Hugo Grotius’ Book II of The Law of War and Peace in 1625.  Recognizing the need for “present danger” and threatening behavior that is “imminent in a point of time,” Grotius indicates that self defense is to be permitted not only after an attack has been suffered, but also in advance, that is, “where the deed may be anticipated.”  Or, as he explains a bit further on in the same chapter, “It be lawful to kill him who is preparing to kill….”

               A similar position was taken by Emmerich de Vattel.  In Book II of The Law of Nations (1758), Vattel argues:  “The safest plan is to prevent evil, where that is possible.  A Nation has the right to resist the injury another seeks to inflict upon it, and to use force and every other just means of resistance against the aggressor.  It may even anticipate the other’s design, being careful, however, not to act upon vague and doubtful suspicions, lest it should run the risk of becoming itself the aggressor.”[xix]

                Grotius and Vattel draw upon and parallel the early Jewish interpreters, although the latter speak more generally of interpersonal relations than about international relations. Additionally, the Torah contains a prominent provision exonerating from guilt a potential victim of robbery with possible violence if, in self defense, he struck down and if necessary even killed the attacker before he committed any crime.  (Ex.  22:1). In the precise words of the rabbis, “If a man comes to slay you, forestall by slaying him!”  (Rashi; Sanhedrin 72a).

                Grotius and Vattel both caution against abusing the right of anticipatory self defense as a pretext for aggression, but this is an abuse that Israel, in its current relationship with Iran, could commit.  As Iran clearly considers itself in a condition of war with Israel, any Israeli preemption against this nuclearizing adversary might not actually represent an authentic act of anticipatory self-defense, but rather just one more military operation in an ongoing or protracted war.  In such definitional circumstances, the Israeli military operation’s legality would have to be appraised in terms of its apparent conformance or nonconformance with relevant laws of war of international law (jus in bello).

               Jurisprudentially, to identify any such operation as an act of aggression against another state that already considered itself at war with Israel would be nonsense.

Background of Permissible Preemption in Law

               Even if Iran  were not in a condition of belligerence with the Jewish state, a condition periodically amplified by Tehran’s open calls for Israel’s annihilation,an Israeli preemptive action could still be law-enforcing.  Israel, in the fashion of every state under world law, is peremptorily entitled to existential self-defense.  Today, in an age of uniquely destructive weaponry, international law does not require Israel or any other state to expose its citizens to atomic destruction. Inter alia, especially in circumstances where active hostilities already obtain (i.e., in times of conventional warfighting), Israel’s license to attack Iranian nuclear facilities could be unassailable.

                The right of self-defense, we learn from Emmerich de Vattel, gives rise to the “right to resist injustice.”  According to the Swiss scholar’s argument at Chapter V of the Law of Nations, or the Principles of Natural Law (1758), “On the Observance of Justice between Nations:”

                              Justice is the foundation of all social life and the secure bond of all civil intercourse.  Human society, instead of being an interchange of friendly assistance, would be no more than a vast system of robbery if no respect were shown for the virtue which gives to each his own.  Its observance is even more necessary between Nations than between individuals, because injustice between Nations may be followed by the terrible consequences involved in an affray between powerful political bodies, and because it is more difficult to obtain redress. An intentional act of injustice is certainly an injury.  A Nation has, therefore, the right to punish it…. The right to resist injustice is derived from the right of self-protection.[xxvii]

               The customary  right of anticipatory self defense has its modern origins in the Caroline incident, an event that concerned the unsuccessful rebellion of 1837 in Upper Canada against British rule (a rebellion that aroused sympathy and support in the American border states). Following this landmark event, the serious threat of armed attack has generally been taken to justify a state’s militarily defensive action. In an exchange of diplomatic notes between the governments of the United States and Great Britain, then U.S. Secretary of State Daniel Webster outlined a framework for self defense which did not require an actual attack.  Here, military response to a threat was judged permissible so long as the danger posed was “instant, overwhelming, leaving no choice of means and no moment for deliberation.”

               In certain distinctly residual circumstances, permissible forms of anticipatory self-defense could be expressed via assassination/targeted killing (although classical philosophical and jurisprudential arguments supporting assassination are usually cast  more narrowly in terms of a tyrannicide motif). Representing an alternative or addition to standard military forms of preemption, such targeted killing, in order to be consistent with appropriate international legal expectations, would need to be undertaken when the danger posed to Israel actually met the specific test of the Caroline.  If the targeted killing were undertaken only to destroy the potential threat of an enemy, i.e., as a preventive action, it would not qualify as permissible in law. 

               If, however, the assassination were undertaken in anticipation of some immediate or credibly expected enemy aggression, it couldstill qualify as “anticipatory self-defense.”

               To be sure, there are antecedent problems.  First, in the “real world,” judgments concerning the immediacy of anticipated aggression are exceedingly difficult to make.  Second, even where such judgments are ventured, it can never by altogether clear whether the degree of immediacy is sufficient to invoke preemption rather than prevention.  Third, in meeting the legal requirements of defensive intent, a state may have to act preventively rather than preemptively, because waiting to allow a threat to become more immediate could have decisively or even intolerably negative strategic/tactical consequences. And fourth, the actual state-preserving benefits that might accrue from the assassination of enemy leaders are apt to be contingent upon not waiting until the danger posed is “instant, overwhelming, leaving no choice of means and no moment for deliberation.”

               Some scholars argue that the customary right of anticipatory self defense articulated by the Caroline has been overridden by the specific language of Article 51 of the UN Charter In this view, Article 51 fashions a new and more restrictive statement of self defense, one that relies on the literal qualification contained at Article 51, “….if an armed attack occurs.”  Still, this interpretation ignores that international law cannot compel a state to wait until it absorbs a devastating or lethal first strike before acting to protect itself.

               Recalling Cicero: “The safety of the people shall be the highest law.”

               There is more. The argument against a more restrictive view of self-defense is reinforced by the evident weaknesses and partisan inclinations of the U.N. Security Council in offering collective security against an aggressor state.  Both the Security Council and the General Assembly refused to censure Israel for its 1967 preemptive attack against certain belligerent Arab states. This refusal signified implicit approval by the United Nations of Israel’s 1967 resort to anticipatory self defense.

               Before Israel could persuasively argue any future instances of anticipatory self defense under international law, however, a verifiable case would have to be made that Jerusalem had first sought to exhaust all available means of peaceful settlement. Even a very broad view of anticipatory self defense cannot relieve a state of this peremptory obligation codified inter alia at Article 1 and at Article 2(3) of the UN Charter. Strictly speaking, these obligations should not necessarily be binding upon Israel because of the de facto condition of belligerency created and sustained by Iran, but the global community generally seems to have ignored these conditions.  It follows that Israel, should it ever decide upon exercising preemption against Iran, would be well advised to remind all concerned of its own consistent and comprehensive efforts at authentic peaceful settlement.

Jewish-Historical Background and Future Genocide Against Israel

               The origins of such advice would have certain deep roots in ancient Israel.  According to Grotius, citing to Deuteronomy in The Law of Prize and Booty, the Israelites were exempted from the issuance of warning announcements when dealing with previous enemies (what we might reference today as an ongoing or protracted war, precisely the condition that currently obtains between Israel and Iran.) The Israelites, recounts Grotius, had been commanded by God to “refrain from making an armed attack against any people without first inviting that people, by formal notification, to establish peaceful relations ….”  “Yet,” he continues, “the Israelites…

                              thought that this prohibition was inapplicable to many of the Canaanite tribes, inasmuch as they themselves had previously been attacked in war by the Canaanites.”

“Hence,” says Grotius, “we arrive at the following deduction”:

                              Once the formality of rerum repetitio has been observed, and a decree on the case in question has been issued, no further proclamation or sentence is required for the establishment of that right which arises in the actual process of execution.  For [and this is especially relevant to modern Israel] in such circumstances, one is not undertaking a new war but merely carrying forward a war already undertaken.  Thus the fact that justice has once been demanded and not obtained, suffices to justify a return to natural law….

               Genocide is a word with very precise jurisprudential meaning.  Codified at the Genocide Convention, a treaty that entered into force on January 12, 1951, it means any of a series of stipulated acts “committed with intent to destroy, in whole or in part, a national, ethnical, racial or religious group as such….”  The key to understanding and identifying genocide lies in the phrase, “intent to destroy.”  Ipso facto, identifying Israeli warfare against terrorist infrastructures in Gaza as “genocidal” is entirely propagandistic. By meaningful legal standards, any such identifications are falsehoods. And because these identifications are often made by openly “perfidious” adversaries (state, sub-state or “hybrid”), egregious Iranian falsity is reinforced by unhidden Iranian violations of humanitarian international law.

               Genocide has a long and not so complicated history. Outside of Iran, active support in parts of the Arab world for genocide against the Jews is a matter of long historical record. Even before creation of the State of Israel, such support was displayed openly and enthusiastically during the Holocaust. On November 28, 1941, the Grand Mufti of Jerusalem, Haj Amin, met in Berlin with Adolph Hitler.  The purpose of this meeting, which followed Haj Amin’s organization of SS troops in Bosnia, was to ensure cooperation on “The Jewish Question.”  It was necessary, Haj Amin insisted, that all Jews be sent to countries “where they would find themselves under active control, for example, in Poland, in order thereby to protect oneself from their menace and avoid the consequent damage.”

                Neither Palestine as a UN “Non-Member Observer State” nor any already sovereign Arab state has ever publicly criticized the Mufti’s strong support for the Nazi Holocaust. During the 1950s and 1960s, Adolph Hitler remained an enormously popular figure in the Arab world, a popularity now being reignited in Iran.  Unsurprisingly, responses in this region to the Eichmann trial in Jerusalem (1961) generally treated the mass murderer as a “martyr,” and congratulated the Nazi war criminal for having “conferred a real blessing on humanity” by enacting a “final solution.”[xli] Looking ahead, Iran’s intended “solution” for Israel is a second “Final Solution.”

“Palestine” and Iran

               Overall, Israel’s complex security situation is fraught not only with unprecedented danger, but also with very grave irony.  Before Israel could begin to move seriously toward Palestinian sovereignty and independence, toward a “two-state solution,” any Iranian regime preparing for major war against Israel would have to reverse such preparations. This is because Israel could not possibly afford to confront the existential risks of another hostile Islamic state on its borders. 

               In the absence of such policy reversal in Iran, the creation of Palestine would affect Israel’s inclination to preempt. Because of Israel’s small size and corresponding lack of “strategic depth” (the Jewish State is smaller than America’s Lake Michigan), its inclination to strike first at Iranian hard targets would become especially high.  Deprived of strategic depth, Israel could not hold out for as long as was likely possible when Palestine was still merely a pre-state “authority.” 

               It is at least conceivable that a post-Palestine shift in Israeli nuclear strategy from deliberate ambiguity to disclosure could reduce Israel’s understandable incentive to preempt, but only if Jerusalem had first been made to believe that its nuclear deterrent threat was being taken with sufficient seriousness by Iran.

               Several corollary problems will need to be considered.  First, how would Israel’s leadership know that taking the bomb out of the “basement” had actually improved its deterrence posture?  To a certain extent, the credibility of Jerusalem’s nuclear threats would be contingent upon the severity of different provocations.  It might be believable if Israel were to threaten nuclear reprisals for provocations that endanger the physical survival of the state, but it would almost certainly be less believable to threaten such reprisals for relatively minor territorial infringements or incursions. One “grey area” provocation could involve a growing Iranian threat to use radiation dispersal weapons, a quasi-nuclear option that might be combined with Iranian rocket attacks on Israel’s nuclear reactor at Dimona.

               There will be other problems and complexities.  To function successfully, Israel’s deterrent, even after being removed from the “basement,” would have to be rendered secure from Iranian preemptive strikes. Israel must also remain wary of “decapitation,” of losing the “head” of its military command and control system, because of enemy first-strike aggressions.  Should Israel’s enemies be unpersuaded by Jerusalem’s conspicuous move away from deliberate ambiguity, – a move intended to enhance Israel’s nuclear deterrent – they might then initiate such strikes as could tangibly immobilize Israel’s order of battle.

               What then?

               A contrary argument about the effects of Palestine on Israel’s inclination to preempt suggests that because of Israel’s newly expanded vulnerability, its nuclear deterrent could become more credible than ever before.  As a result, Jerusalem could now better afford not to strike first than when it still administered disputed Palestinian territories.  In this situation, the principal benefit of shifting from ambiguity to disclosure would seem to lie in an explicitly-identified escalation ladder, revealing a broad array of intended Israeli reprisals, ranging from limited conventional responses to measured or calibrated nuclear strikes.

               In weighing the different arguments concerning the effect of Palestine upon an Israeli preemption, particular attention must be directed toward Israel’s presumptions about the inevitability of war with Iran and its long-term expectations for Iranian vulnerability.  Should Israel’s leaders conclude that the creation of Palestine would make major war with Iran more-or-less inevitable, and that, over time, Iranian vulnerability to Israel would likely diminish, Jerusalem’s inclination to strike first could be increased.  To a certain extent, Israel’stactical judgments on preemption will be affected by antecedent decisions on nuclear strategy, namely decisions concerning “countervalue” vs. “counterforce” objectives. 

               In making its nuclear choices, Israel will have to confront a paradox.  Credible nuclear deterrence, essential to security and survival in a world made more dangerous by the creation of Palestine, would require “usable” nuclear weapons.  If these weapons were obviously inappropriate for any reasonable objective, they would not deter. 

               All things considered, Israel, if confronted by a new state of Palestine, would be well-advised to do everything possible to prevent the appearance of a nuclear Iran, possibly including variously pertinent non-nuclear preemptions.  Under these portentous conditions, Israel would require a very believable (and hence usable) nuclear deterrent, one that could be employed without igniting “Armageddon” for regional belligerents and that could serve some damage-limiting military purpose (whatever the collateral effects) against Iranian weapons (nuclear and non-nuclear) should deterrence fail.

               Creation of a fully-sovereign Palestine could have a dramatic effect on Jerusalem’s decisions concerning anticipatory self-defense. Israel’s extant nuclear weapons status and strategy would impact and influence this vital decision.  More precisely, should Israeli decision-makers determine that the country’s nuclear weapons could support preemption by deterring Iran from retaliating, this “atomic factor” could encourage Israeli defensive first strikes.  If, on the other hand, Jerusalem were to calculate that Iran or (in the future) other prospective target states would be unimpressed by any threats of an Israeli nuclear counter-retaliation, this variable would likely not encourage defensive first strikes.

Israel’s Nuclear Strategy and Law-based Preemptions

               Could the precise form of Israel’s nuclear strategy make a difference in shaping these circumstances?  Relying upon nuclear weapons not to deter Iranian first strikes, but to support its own preemptive attacks, Israel would have to choose between continued nuclear ambiguity (implicit threats) and nuclear disclosure (explicit threats).  How should it choose?

               More than anywhere else, the answer lies in Jerusalem’s confidence that its adversaries already acknowledgeIsrael’s “calibrated” nuclear capability.  Should this confidence be high, there could still be variously compelling valid reasons to take the bomb out of the “basement.”  If such confidence were low, the move to disclosure would likely be even more purposeful, because any critical reactions by the United States would be less worrisome for Israel in the “Cold War II” strategic environment.

               What about Afghanistan? On its face, the fall of that “graveyard of empires” revealed no verifiably direct connections to Israel’s national security. Nonetheless, the overwhelming defeat of its American patron in that volatile region could have decipherable “spillover effects” for Israel. Most realistic, in this regard, would be emboldened sub-national Islamist adversaries (e.g., Sunni Hamas, Shiite Hezbollah, Shiite Houthi, ISIS-K); expanded strife between pertinent enemies and unstable states (e.g., Taliban vs. ISIS-K); and additional geo-strategic influence for the already-nuclear Islamic state of Pakistan). This last result would likely elicit “countervailing” reactions from India and/or China, reactions that could not be ignored by Russia.

               In view of what is now generally believed throughout the Middle East and the wider world, there is good reason to assume that Israel’s “ambiguous” nuclear arsenal could be nuanced to meet strategic particularities of any specific threat. Israel’s enemies already share this key assumption and likely need no further convincing about Jerusalem’s basic nuclear capacities.  The most critical questions about Israel’s nuclear deterrent would not be about capability, but willingness.  How likely is it that Israel, after launching non-nuclear preemptive strikes against Iranian hard targets, would respond to enemy reprisals with any sort of nuclear counter-retaliation?

               These are all bewildering matters. What will Israeli planners conclude?  The answer depends in part upon their view of Iran’s expectedly reciprocal judgments concerning Israel’s leaders.  Do these judgments suggest a leadership that believes it can gain the upper hand with nuclear counter-retaliation?  Or do they suggest a leadership that believes such counter-retaliation would bring upon Israel variously intolerable levels of adversarial harm and destruction?

                Depending upon the way in which the pertinent Iranian decision-makers interpret Israel’s authoritative perceptions, they will accept or reject the cost-effectiveness of a non-nuclear retaliation against Israel.  This implies that it is in Israel’s best interest to communicate the following strategic assumption to its relevant enemies: Israel would be acting rationally by responding to certain enemy non-nuclear reprisals to Israeli preemptive attacks with a nuclear counter-retaliation. The plausibility of this assumption could be enhanced if the Iranian enemy reprisals were to involve chemical and/or biological weapons.

               All of these calculations assume rationality.  In the absence of calculations that compare the costs and benefits of strategic alternatives, what will happen in the Middle East must always remain a matter of conjecture. The prospect of non-rational judgments in the region is always plausible, especially as the influence of Islamist/Jihadist ideology remains strongly determinative among Iranian decisional elites.

               To the extent that Israel might one day believe itself confronted with non-rational state enemies, particularly ones with highly destructive weapons in their arsenals, its incentive to preempt could become overwhelming.  In fact, should such enemies ever be believed to hold nuclear weapons, Israel could even decide rationally to launch a nuclearpreemption against these enemy arsenals.  This would appear to be the only calculable circumstance in which a rational Israeli preemptive strike could ever be nuclear.

               Iran should understand from all this that there are foreseeable conditions wherein Jerusalem might decide to actually use its nuclear weapons. These conditions would concern the staggering prospect of total military defeat. Faced with imminent destruction of the state, Israel’s leaders would almost certainly do whatever is needed to survive, including a resort to nuclear retaliation, nuclear counter-retaliation, nuclear preemption or (most “residual” of all) nuclear war-fighting.

Nuclear Retaliation

               Israel’s overriding purpose in any conventional war with Iran should be to preemptively destroy that enemy country’s advancing nuclear infrastructures. But if this legitimate purpose were not met, Israel could then have to face an already-nuclear Iranian foe. In such perilous and altogether unprecedented circumstances, if Iran sometime chose to launch a nuclear first-strike against Israel, Jerusalem would expectedly respond, to whatever extent deemed possible and necessary, with a nuclear retaliatory strike.  If Iran’s first-strikes were to involve other forms of unconventional weapons, i.e., chemical and/or biological weapons, Israel might still launch a measured nuclear reprisal, depending, in large but ambiguous measure, upon Jerusalem’s expectations of follow-on aggression and its associated calculations of comparative damage-limitation. 

               If Israel were to absorb a massive conventional attack, a nuclear retaliation could not automatically be ruled out, especially (but not exclusively) if: (a) the Iranian aggressor were perceived to hold nuclear and/or other unconventional weapons in reserve; and/or (b) Israel’s leaders were to believe that non-nuclear retaliations could not prevent genocidal destruction of the Jewish state.  A nuclear retaliation by Israel could be ruled out only in those circumstances wherein Iranian aggressions were clearly conventional, “typical” (i.e., consistent with previous instances of enemy attack, in both degree and intent) and hard-target directed.

Nuclear Counter Retaliation

               Should Israel feel compelled to preempt Iranian aggressions with conventional weapons, the Iranian response would largely determine Jerusalem’s next moves.  If this response were in any way nuclear (though not yet possible), Israel would assuredly resort to nuclear counter-retaliation.  If this retaliation were to involve chemical and/or biological weapons, Israel might also feel pressed to take the escalatory initiative – again, depending upon Jerusalem’s considered judgments of Iranian intent and its informed calculations of essential damage-limitation. 

               Should the Iranian response to Israel’s preemption be limited to hard-target conventional strikes, it is unlikely that Jerusalem would move on to nuclear counter-retaliations.  If, however, the Iranian conventional retaliation was all-out and directed toward civilian populations as well as to military targets, an Israeli nuclear counter-retaliation could not be ruled out ipso facto.  It would appear that such a counter-retaliation couldbe ruled out only if the enemy conventional retaliation were ascertainably proportionate to Israel’s preemption, confined exclusively to Israeli hard-targets, circumscribed by the jurisprudential limits of “military necessity”  and accompanied by believable assurances of non-escalatory intent.

Nuclear Preemption

               It is highly unlikely (perhaps even inconceivable) that Israel would ever decide to launch a preemptive nuclear strike. Though strategic circumstances could arise wherein such a strike would still be determinably rational (i.e., the calculated prospective benefits of the strike would outweigh prospective costs), it is implausible that Israel would ever allow itself to reach such “end-of-the-line” decisional alternatives.  Moreover, unless the nuclear weapons involved were used in a fashion consistent with authoritative expectations of the laws of war – the limits of “distinction,” “proportionality” and “military necessity” –  this form of preemption would represent an egregious violation of international law. 

                Even if such consistency were possible, the psychological/political impact of this activity on the world community would be negative and far-reaching.  It follows that an Israeli nuclear preemption could be expected only:  (a) where Israel’s Iranian enemies had acquired nuclear and/or other unconventional weapons judged capable of destroying the Jewish State; (b) where these enemies had made clear that their intentions paralleled their capabilities; (c) where these enemies were believed ready to begin a “countdown to launch;” and (d) where Jerusalem believed that Israeli non-nuclear preemptions could not achieve the needed minimum levels of damage-limitation, i.e., levels consistent with physical preservation of the polity.

Nuclear Warfighting

               Should nuclear weapons ever be introduced into conflict between Israel and Iran, either by the Jewish State or by Iran, nuclear war-fighting, at one level or another, would ensue.  This would hold true as long as:  (a) enemy first-strikes against Israel would not destroy Jerusalem’s second-strike nuclear capability; (b) enemy retaliations for Israeli conventional preemption would not destroy Jerusalem’s nuclear counter-retaliatory capability; (c) Israeli preemptive strikes involving nuclear weapons would not destroy Iranian second-strike nuclear capabilities; and (d) Israeli retaliation for enemy conventional first-strikes would not destroy Iranian nuclear counter-retaliatory capability.

                It follows from Israel’s strategic requirements that Jerusalem should do whatever is needed to ensure the likelihood of (a) and (b) above, and the unlikelihood of (c) and (d).  This means, among other things, strengthening the hard-target kill capacity of its recognizably survivable and penetration-capable nuclear forces.

               What, exactly, would a nuclear war “mean”?  Even the most limited nuclear conflict would signal genuine catastrophe. Merely the immediate effects of the explosions; thermal radiation, nuclear radiation, and blast damage, could cause intolerably wide swaths of death and devastation. 

               None of this is intended to suggest that an Israeli conventional defensive first-strike would raise the likelihood of a nuclear war. To the contrary, Israel’s resort to a non-nuclear preemption could represent the optimal way to preventa nuclear war, especially if such resort followed Iranian commencement of hostilities. Nothing could be worse for Israel (and possibly its Arab neighbor states as well) than delaying an essential preemption until Iran was “already nuclear.” The very best-case scenario for Israel and its regional Arab neighbors would be to neutralize the impending Iranian nuclear threat withouthaving to launch any preemption, even one undertaken during a pre-nuclear conflict initiated by Iranian “retaliation.” At present, however, there is little or no realistic cause to expect such a scenario.

The More Things Change….

               Plus, ca change, plus c’est la même chose.  “The more things change, the more they remain the same.”  Despite continuous efforts to preserve the state and “safety of the people,” Israel remains subject to variously credible threats of existential harm. The “Jewish State,” notwithstanding the country’s extraordinarily high levels of military technology and international law’s longstanding presumption of juridical solidarity between all states, could soon face literal risks of annihilation. To prevent such an unimaginable prospect, Israel could resort to the assorted legal protections afforded by “anticipatory self-defense.” As we have seen, it would be best for Israel to seek such protections during an already-ongoing conventional war with Iran.

               As long as Israel’s expression of a permissible preemption had been prompted by imminent attack dangers and was executed in verifiable compliance with relevant expectations of distinction, proportionality, and military necessity, the defensive first-strike option could remain lawful. Such lawfulness would not automatically imply corresponding strategic benefits. Analytically, reliable Israeli judgments of legality and efficacy, though overlapping, would remain distinct.

               With a rapidly approaching “eleventh hour,” Jerusalem will need to clarify and enhance its nuclear deterrence policy vis-à-vis Iran. Here, special attention will need to be directed toward codifying and maintaining a recognizably survivable and penetration-capable strategic nuclear force. The nuclear options included in this more conspicuous force would need to range along different points of a well-defined continuum of military destructiveness. Looking forward, Israel requires not an “all or nothing” nuclear deterrent capacity, but a capacitysubject to recognizable forms of “calibration.”

                It will be important for Israel to continuously enhance its ballistic missile defenses, and to convincingly communicate that its diversified nuclear forces are usable and employable as a complement to (not as an alternative) well-planned BMD interceptions. Above all, this communication should include incremental replacement of Israel’s outdated “deliberate nuclear ambiguity” posture with up-to-date policies of “selective nuclear disclosure.”

Israeli Nuclear Deterrence: More Than Just a Game of Chance

                Nuclear deterrence is a “game” that sane national leaders may sometimes have to “play” in the Middle East, but it should always be approached by Israel as a game of strategy, not of chance. In Jerusalem, this means, a continuing willingness to respect the full range of doctrinal complexity – both its own military doctrines and those of enemies such as Iran – and a corresponding determination to forge ahead with reciprocally complex security policies. To successfully influence the choices that Iran would make regarding Israel, Jerusalem will need to clarify that its conventional and nuclear deterrence are seamlessly intersecting and that Israel stands ready to counter enemy attacks at every decipherable level of possible confrontation.

               There remain two final but still-important points to be made in this analysis of Israel, preemption and anticipatory self-defense during conventional war with Iran.

                First, whether Israel’s intersecting and overlapping deterrent processes are geared primarily toward conventional or nuclear threats, their success will ultimately depend upon the expected rationality of the Iranian enemy. In those residual cases where such rationality would appear implausible or improbable, Jerusalem could then find itself under extra pressures to strike promptly, preemptively and comprehensively. For Israel’s survival, regional conflict prospects should always be curtailed at the lowest possible levels of controlled engagement. If at all possible, Israel should avoid having to preempt against an already nuclear Iranian adversary.[lix]

               Second, even the most meticulous plans for preventing a deliberately-inflicted nuclear conflict would not automatically remove attendant dangers of an inadvertent or accidental nuclear war. While an accidental nuclear war would necessarily be inadvertent, there are types of inadvertent nuclear war that need not be caused by mechanical, electrical or computer accident. Such particular but still-fearful forms of unintentional nuclear conflict could represent the unexpected result of misjudgment or simple miscalculation, whether created by (1) singular error or one or both sides of an Israel-Iran nuclear crisis escalation; or by (2) still unforeseen “synergies” arising between discrete decisional miscalculations.

Growing Strategic and Legal Uncertainties for Israel

                Israel, severely injured by the October 7, 2023 Hamas terror attacks, is entering a period of cascading strategic uncertainties. Even if an American President should succeed in bringing the United States and Iran back into viable and law-oriented negotiations, the cumulative harms of Iranian nuclearization are unlikely to be halted or reversed. Considered together with continuously inauspicious strategic developments in other parts of the world, this conclusion signifies a basic obligation for Jerusalem to fashion a progressively refined national strategy of nuclear deterrence and nuclear war avoidance.

               In the end, the truest forms of Israeli military power, whether expressed as “anticipatory self-defense” or as some more comprehensive form of nuclear deterrence, should reflect a triumph of “mind over mind,” not just one of “mind over matter.” Ultimately, Israel’s most compelling forms of influence will need to derive not from the barrel of a gun, rocket or missile, but from the less dramatic advantages of refined intellectual power. In Jerusalem, these advantages should be explored according to twin criteria of law and strategy.  Important to fully understand in Jerusalem, these complex standards would not necessarily be “in synch” with each other.  Realistically, they could be starkly contradictory or opposed.

               For Israel, what will be required for long-term survival is a suitably deep appreciation of decisional complexity and a corresponding willingness to approach all intersecting legal issues from the standpoint of science-based (intellect-driven) inquiry. In the best of all possible worlds, there would be no need for any national considerations of preemption/anticipatory self-defense, but such a world remains a long way off.

               National defense and national security will always have its own specific grammar and syntax. For Israel, confronted by an ever-growing nuclear threat from Iran, the prospect of a significant military preemption is no longer inconceivable. As earlier recognized in May 2013 by then-IDF Chief of General Staff Herzl Halevi, there can come a point wherein even the riskiest defensive first strikes would be cost effective and perfectly rational. The correlative question for Israel is how to determine when such a critical decision-point had actually been reached and what specific harms should be threatened (deterrence) and (if necessary) carried out. This will be a cumulatively complex question.

               One conclusion is already clear. In the prospectively existential matter of a nuclearizing Iran, the outcome of war with Israel could be determined before the opening salvo of any actual military engagement.The first battle of any war, especially an unprecedented nuclear war, must be waged as a dialectical competition of adversarial ideas. This signifies a theory-based struggle acknowledging vast complexities but also more-or-less understating the pitfalls of “friction.” By definition, whatever the changing particularities of any Israel-Iran military confrontation, these pitfalls would concern the gap between “war on paper and war as it actually is.” Accordingly, though a conventional war with Iran would likely offer the best possible context for a cost-effective Israeli preemption, the actual predictability of such a conflict would be low.

               For Israel, per Cicero, “The safety of the People is the highest law.” In the matter of accelerating Iranian nuclearization, the safety of the People of Israel could best be served by waging a just war against Iran while that enemy is pre-nuclear. Though a not-yet-nuclear Iran could still wage catastrophic war against the Jewish State, it would be less catastrophic than a war between two regional nuclear powers. This is the case, moreover, even if an Iran that had just crossed the nuclear threshold were expectedly or verifiably “less powerful” than an already nuclear Israel. In any such nuclear conflict, even a “weaker” Iran (assuming its nuclear weapons were “penetration capable”) could still wreak unacceptable harms on Israel.

               All things considered, if war between Israel and Iran is believed impending, it would be better for Jerusalem to enter such am expected belligerency as the sole nuclear combatant and to wage this belligerency such that this fortunate asymmetry could continue. Nonetheless, even in the midst of a conventional war with Iran, Israel could sometime decide that the compelling expectations of “escalation dominance” had become overwhelming, and that an Israeli escalation to nuclear combat would now be perfectly rational. A decipherable example could involve an Iranian non-nuclear missile attack upon Israel’s Dimona nuclear reactor and/or the tangible combat involvement of already-nuclear North Korea on the side of Iran.

               In all such complex scenarios, Cicero’s counsel would remain purposeful:

               “The safety of the People is the highest law.”

Louis Rene Beres was educated at Princeton(Ph.D., 1971). He is the author of many books and articles dealing with war, terrorism and counter-terrorism, including Terrorism and Global Security: The Nuclear Threat (Westview, 1979), and Apocalypse: Nuclear Catastrophe in World Politics (The University of Chicago Press, 1980).  His twelfth book, Surviving Amid Chaos: Israel’s Nuclear Strategy, was published in 2016 (2^nd ed. 2018).

Professor Beres has examined WMD terrorism for more than fifty years, earlier in consultation with the Nuclear Control Institute, the U.S. Arms Control and Disarmament Agency, the Defense Nuclear Agency (DoD), and the John F. Kennedy Special Warfare Center (USA). His articles have appeared in BESA (Israel); Parameters: The Journal of the U.S. Army War College (Pentagon); Special Warfare (Pentagon); The Israel Journal of Foreign Affairs; International Security (Harvard); Harvard National Security Journal (Harvard Law School); Yale Global (Yale University); World Politics (Princeton); Bulletin of the Atomic Scientists; Air-Space Operations Review (USAF); Jewish Business News; The War Room (Pentagon); Modern War Institute (West Point); The International Journal of Intelligence and Counterintelligence; and Oxford University Press Annual Yearbook of International Law and Jurisprudence (Oxford University Press). The Chair of Project Daniel (Israel, PM Sharon, 2003-2004), Dr. Beres’ work is known to both American and Israeli intelligence communities. He was born in Zürich, Switzerland at the end of World War II.

This article was first published in Modern Diplomacy