“The worst does sometimes happen.” - Friedrich Durrenmatt, Swiss playwright

In separate but interdependent parts of the world, a nuclear war is conceivable and more-or-less probable. Nonetheless, ascertaining any precise or usable hierarchy of probabilities would be impossible. In logic and science, such judgments are indeterminable for unique events.

Always.

In the Middle East or anywhere else, a nuclear war would be sui generis, a unique event. By definition, it would lie beyond any reliable judgments of probability. Still, Israel's nuclear weapons and doctrine must remain integral to the country’s survival. This calculation is especially credible today because of growing prospects for a nuclear war involving Russia, Ukraine, China, North Korea, Pakistan or Iran. Even if the nuclear war threshold were first crossed elsewhere, the glowing portents of any such unprecedented conflict would be universal.

In the early 1950s, David Ben-Gurion, Israel's first prime minister, understood the need for an "equalizer" to secure his vulnerable country’s safety in a world of traditional anarchy and prospective chaos. Even without an exact science of prediction, Ben Gurion recognized that appropriate nuclear assets could prove indispensable to national survival. Ironically, as the term has evolved in this Middle Eastern geopolitical context, “appropriate” means a nuclear military capacity that is not necessarily too destructive (i.e., not expressly oriented to threats of “massive retaliation”) and that is “deliberately ambiguous.”

There is more. No category of weapons is powerful per se. Rather, all weapons of war, even nuclear ones, must be informed by task-suitable strategies and tactics. How, then, should Israel’s “bomb in the basement” be "used?" Whatever answers might be offered, any such complex task should be viewed by Israeli policy planners and decision-makers as an intellectual one. Whatever its national nuclear doctrine, Israel’s objective should always be deterrence ex ante, not revenge ex post.

In the atomic era’s “good old days,” when Americans and Soviets were busily defining a narrowly bipolar Cold War nuclear strategy ex nihilo, out of nothing, Israel had nowhere to turn for history-based policy guidance. What Jerusalem did understand, from the start, is that nuclear ordnance can succeed only through certain calibrated policies of intentional non-use. This seemingly paradoxical understanding represented a contemporary reaffirmation of classical Chinese strategist Sun-Tzu in the Art of War: "Subjugating the enemy's army without fighting is the true pinnacle of excellence."

Sun. Tzu’s ancient observation is just another way of describing military deterrence in general; that is, as a national security posture by which specified adversaries can be reliably discouraged from striking first. Deterrence only works to the extent that prospective aggressors are able to calculate that the expected costs of striking first will exceed expected gains. For the most part, this reasoning relates to all manner of violent conflict.

There are assorted policy prerequisites. Israel’s designated adversaries must always be considered rational and must usually be nation-states. At times, however, these states could operate in tandem with other states (alliance) or terror groups (hybrid). As a foreseeable example, Israel's enemies could include sub-state foes preparing to targeting the Osiraq nuclear reactor with non-nuclear weapons.

For the present time, unless analysts were to consider Pakistan as an authentic national foe, Israel has no already-nuclear enemies. An unstable Islamic state, Pakistan is potentially subject to coup d'état by Jihadist elements and is closely aligned with Saudi Arabia. Non-Arab Iran leads a widening array of heavily armed Shiite proxies and militias. Significantly, Tehran supplies missiles to Yemen's Houthi Ansar al-Allah Shiite army, which previously fired them at Saudi cities.

At one level, Iran's missile strikes against ISIS and post-ISIS targets in eastern Syria represent a search for "escalation dominance" in the regional conflict between radical Shiites and Sunnis. Here, for the first time since the eight-year Iran-Iraq war during the 1980s, Damascus used advanced solid fuel ballistic missiles. Over time, such escalations could unexpectedly include nuclear warheads, not against insurgent targets but against a formidable enemy state such as Saudi Arabia or Israel.

In these dialectical calculations, Israel must remain intellectually creative and conceptually well-prepared. For nuclear deterrence to work long-term, would-be aggressor states might need to be told more rather than less about (1) Israel's pertinent nuclear targeting doctrine; and (2) the expected invulnerability and penetration-capability of Israel’s nuclear forces. However counter-intuitive, this means that to best prepare for all plausible attack scenarios, Israel should plan conscientiously and conspicuously for the incremental replacement of "deliberate ambiguity" with certain apt levels of "nuclear disclosure."[1]

Though the only true and continuous purpose of Israel’s nuclear weapons should be deterrence at variously foreseeable levels of military destructiveness, there will still remain residual circumstances under which Israeli nuclear deterrence could fail. How might such circumstances actually arise? Four principal though not mutually exclusive scenarios should come immediately to mind.

(1) Nuclear Retaliation

Should an enemy state or alliance of enemy states ever launch a nuclear first-strike against Israel, Jerusalem would respond, assuredly, and to whatever extent possible, with a nuclear retaliatory strike. If enemy first-strikes were to involve other available forms of unconventional weapons, such as chemical or biological weapons of mass destruction (WMD), Israel might then still launch a nuclear reprisal. This grave decision would depend, in large measure, upon Jerusalem's informed expectations of any follow-on enemy aggression and on 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 if: (a) the state aggressors 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 annihilation of the state. A nuclear retaliation by Israel could be ruled out only in those rapidly discernible circumstances where enemy state aggressions were clearly conventional, "typical" (that is, consistent with all previous instances of attack, in both degree and intent) and hard-target oriented (that is, directed towards Israeli weapons and related military infrastructures rather than its civilian populations).

(2) Nuclear Counter retaliation

Should Israel ever feel compelled to preempt enemy state aggression with conventional weapons, the target state(s)' response would largely determine Jerusalem's next moves. If this response were in any way nuclear, Israel would doubtlessly turn to some available form of nuclear counter retaliation. If this retaliation were to involve other non-nuclear weapons of mass destruction, Israel could also feel pressed to take the escalatory initiative. Again, this decision would depend upon Jerusalem's judgments of enemy intent, and upon its corollary calculations of essential damage-limitation.

Should the enemy state response to Israel's preemption be limited to hard-target conventional strikes, it is unlikely that decision-makers would then move to any nuclear counter retaliations. If, however, the enemy conventional retaliation was "all-out" and directed toward Israeli civilian populations as well as to Israeli military targets, an Israeli nuclear counter retaliation could not be excluded. Such a counter retaliation could be ruled out only if the enemy state's conventional retaliation were identifiably proportionate to Israel's preemption; confined to Israeli military targets; circumscribed by the legal limits of "military necessity;" and accompanied by explicit and verifiable assurances of non-escalatory intent.

(3) Nuclear Preemption

It is implausible that Israel would ever decide to launch a preemptive nuclear strike. Although circumstances could arise wherein such a strike would be both perfectly rational, and permissible under authoritative international law,[2] it is unlikely that Israel would ever allow itself to reach such irremediably dire circumstances. Moreover, unless the nuclear weapons involved were usable in a fashion still consistent with longstanding laws of war, this most extreme form of preemption could represent an expressly egregious violation of international law.

Even if such consistency were possible, the psychological/political impact on the entire world community would be strongly negative and far-reaching. This means that an Israeli nuclear preemption could conceivably be expected only: (a) where Israel's pertinent state enemies had acquired nuclear and/or other weapons of mass destruction judged capable of annihilating the state; (b) where these enemies had made it clear that their intentions paralleled their genocidal capabilities; (c) where these enemies were believed ready to begin an operational "countdown to launch;" and (d) where Jerusalem believed that Israeli non-nuclear preemptions could not achieve the needed minimum levels of damage-limitation - that is, levels consistent with physical preservation of the state.

(4) Nuclear War fighting

Should nuclear weapons ever be introduced into any actual conflict between Israel and its many enemies, either by Israel, or by a regional foe, nuclear war fighting, at one level or another, could ensue. This would hold true so long as: (a) enemy first-strikes would not destroy Israel's second-strike nuclear capability; (b) enemy retaliations for an Israeli conventional preemption would not destroy the Jewish State's nuclear counter retaliatory capability; (c) Israeli preemptive strikes involving nuclear weapons would not destroy enemy state second-strike nuclear capabilities; and (d) Israeli retaliation for conventional first-strikes would not destroy the enemy's nuclear counter retaliatory capability.

This means that in order to satisfy its most fundamentals survival imperatives, Israel must take appropriate steps to ensure the likelihood of (a) and (b) above, and the simultaneous unlikelihood of (c) and (d).

A nuclear war involving Israel is conceivable. Israel’s corresponding responsibility is to prepare prudently and systematically for all corollary contingencies, even when any such express preparation would appear intolerably expensive, operationally daunting and diplomatically disquieting. For Israel, national survival in the nuclear age must always be about what ancient Greeks and Macedonians described as the struggle of "mind over mind," not merely one of "mind over matter."

For Israel, a tiny country without reassuring strategic depth, the most primary and consequential "battlefield" will always be analytical.

Retrospectively, if all goes according to plan, there will have been diligent strategic considerations of enemy rationality as well as tangible shifts from deliberate nuclear ambiguity to selective nuclear disclosure. Without meeting such increasingly urgent intellectual prerequisites, a catastrophic conflict, whether nuclear, biological and/or conventional, could become more than conceivable. It could become unavoidable.

“The worst does sometimes happen.”

Louis René Bereswas educated at Princeton (Ph.D., 1971) and is the author of many books, monographs, and articles dealing with Israeli nuclear strategy. Emeritus Professor of International Law at Purdue, he has lectured on this topic for almost fifty years at leading universities and academic centers for strategic studies. Dr. Beres' twelfth book, Israel's Nuclear Strategy: Surviving amid Chaos, was published by Rowman and Littlefield, in 2016 (2nd ed., 2018). https://paw.princeton.edu/new-books/surviving-amid-chaos-israel%E2%80%99s-nuclear-strategy

In December 2016, Professor Beres authored a monograph at Tel-Aviv University (with a special postscript by retired USA General Barry McCaffrey), Israel's Nuclear Strategy and American National Security. https://sectech.tau.ac.il/sites/sectech.tau.ac.il/files/PalmBeachBook.pdf During 2003-2004, he was Chair of “Project Daniel” (PM Ariel Sharon). Dr. Louis René Beres was born in Zürich, Switzerland at the end of World War II.