In an increasingly chaotic Middle East, Israel may sometime best deter its foes by feigning irrationality.

In complex matters of nuclear deterrence, some suggestions may first appear counterintuitive. One such suggestion: Appearing “too rational” in the face of certain adversaries could be a liability. A too-conspicuous rationality, it is supposed, might sometime undermine stable nuclear deterrence. This ironic and seemingly eccentric argument must apply especially to an imperiled country of limited mass: the state of Israel.

Back in the pre-nuclear 19th century, Prussian military theorist Carl von Clausewitz already understood that in war, and also in corollary preparations for war, “mass counts.” Significantly, Israel, a country smaller than America’s Lake Michigan, remains beleaguered on all sides by assorted state and sub-state enemies. Some of these enemies, as Jerusalem well understands, could sometime choose to feign irrationality – a strategy selected to get a jump on Israel in any ongoing competition for escalation dominance. Also still plausible, these very same enemies could decide to actually be irrational.

By definition, this second more-or-less credible prospect would mean valuing certain specific preferences (e.g., presumed Islamic religious obligations) even more highly than national survival. For Israel, the daunting vision of a genuinely irrational nuclear adversary is most concerning with particular regard to Iran. To be sure, there is understandably little confidence in Israel that the international nuclear agreement reached in Vienna will have any meaningful impact on Iranian nuclearization.

How should Israel proceed? In narrowly military terms, the very best option would seem to be preemption; that is, a defensive first strike directed against Iran’s pertinent hard targets. Nonetheless, it is already very late for launching any operationally cost-effective preemption against Iran, and – even if it could be properly defended in law as “anticipatory self-defense” – such action would likely come at a too-staggering human and political cost.

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In essence, this implies a now primary obligation for Israel to focus on enhancing its nuclear deterrence posture. Here, Jerusalem must always bear in mind this posture’s core focus on prevention rather than punishment. By definition, using its presumed nuclear forces for vengeance rather than deterrence would miss the point. Arguably, in fact, any such Israeli use, even as a residually default option, would be not only purposeless but also irrational.

There is more. Israel’s nuclear deterrent must always be backed up by appropriate systems of active defense (ballistic missile defense), but especially if there should be good reason to fear an irrational nuclear adversary. Although it is well-known that no system of active defense, including even Israel’s very promising Arrow system of ballistic missile defense, can ever be “leak-proof,” there is still good reason to suppose that certain ballistic missile defense deployments could help safeguard both Israeli civilian populations (soft targets) and Israeli nuclear retaliatory forces (hard targets). It follows, inter alia, that Arrow and certain corollary systems will remain a necessary complement to the Jewish state’s comprehensive nuclear deterrence posture.

“Everything is very simple in war,” says Clausewitz in “On War,” “but the simplest thing is difficult.” To progress, Israel’s military planners must expressly identify the prioritized goals of the Jewish state’s nuclear deterrence posture. Before any rational adversary of Israel could be suitably deterred by an Israeli nuclear deterrent, that enemy would first need to believe that Israel had assuredly maintained both the capacity to launch appropriate nuclear reprisals for certain forms of aggression (nuclear and perhaps non-nuclear) and also the will to undertake any such uniquely consequential launch. In more perplexing matters involving any expectedly irrational nuclear enemy, successful Israeli deterrence would need to be based upon threats to certain enemy values other than national survival.

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Further, Israel would need to demonstrate, among other things, the substantial invulnerability of its own nuclear retaliatory forces to any enemy first-strike aggressions. More precisely, in this connection, it will be in Israel’s long-term survival interests to continue to commit to assorted submarine-basing nuclear options. Otherwise Israel’s land-based strategic nuclear forces could sometime present to an existential enemy as invitingly too vulnerable.

Whether or not Israel should actually proceed with any more explicit submarine-basing of its presumed nuclear retaliatory forces, Jerusalem could still benefit from a carefully controlled and incrementally phased end to “deliberate nuclear ambiguity.” Indeed, without such a calculated termination to the country’s “bomb in the basement,” there could sometime arise serious enemy doubts about Israel’s nuclear deterrent, pertinent questions that could prove even more persuasive about Israel’s perceived willingness and capacity to make good on its (stubbornly still implicit) nuclear retaliatory threats.

Above all, looking ahead, Israel will have to rely increasingly on a multifaceted doctrine of nuclear deterrence. In turn, certain elements of this “simple but difficult” doctrine will soon need to be rendered less ambiguous. This complex modification will imply an even more determined focus on prospectively rational and irrational enemies, including both national and subnational foes.

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To deal most successfully with its presumptively irrational or non-rational enemies, Israel will likely need to compose an original strategic playbook. It may even be necessary for Israel to consider, at least on occasion, feigning irrationality itself. In such cases, however, it will be important for Jerusalem not to react in ad hoc fashion to each arising challenge, but rather to derive or extrapolate all of its specific policy reactions from a carefully pre-fashioned strategic nuclear doctrine. Without such suitable doctrine as a guide, pretended irrationality could quickly become a double-edged sword, effectively bringing more rather than less strategic risk to Israel.

Years ago, when he was minister of defense, Israeli Gen. Moshe Dayan had instructed that “Israel must be seen as a mad dog, too dangerous to bother.” Dayan may have seized upon an instructive and timely metaphor. Clausewitz, for one, who had much earlier favored “audacity” in war, would likely have agreed.

There is one last but still vital observation. It is improbable but not inconceivable that certain of Israel’s principal enemies would be neither rational nor irrational, but mad. While irrational decision-makers would already pose special problems for Israeli nuclear deterrence – because these decision-makers would not value collective survival more highly than any other preference or combination of preferences – they could still be susceptible to alternate forms of deterrence. For example, like rational decision-makers, they could still maintain a fixed, determinable and transitive hierarchy of preferences, meaning, at least in principle, that they could still be deterred.

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Mad or so-called crazy adversaries, on the other hand – and by definition – would have no such calculable hierarchy of preferences and would therefore not be subject to any strategy of Israeli nuclear deterrence. Although it could be far worse for Israel to sometime have to face a mad nuclear enemy than a merely irrational one, Jerusalem will have no foreseeable choice in this matter. This means that Israel, like it or not, will need to maintain, perhaps even forever, a three-track system of nuclear deterrence and defense, one track each for its adversaries that are presumed (1) rational; (2) irrational; or (3) mad. For the utterly unpredictable third track, special plans will also need to be maintained for undertaking presumptively indispensable preemptions, and, simultaneously, for certain corresponding efforts at ballistic missile defense.

In the increasingly chaotic Middle East, Israel’s nuclear strategy will represent that country’s ultimate existential protection. To best fashion this all-important strategy, Jerusalem must pay especially close attention to multiple considerations of enemy rationality, and, reciprocally, to those most promising ways in which Israel’s own nuclear posture should be made persuasive to its foes. One such way, linked in part to a doctrinal shift away from “deliberate nuclear ambiguity,” could involve certain long-ignored elements of pretended irrationality.

Reprinted with author’s permission from US News