"I will do such things – What they are yet, I know not – but they shall be the terrors of the earth." (Shakespeare, King Lear)
It is frequently assumed, incorrectly, that Israel's nuclear weapons and strategy are irrelevant to non-nuclear threats. This erroneous assumption stipulates, albeit implicitly, that (1) extraordinary ordnance and posture must pertain exclusively to roughly parallel levels of prospective enemy destructiveness; and that (2) non-nuclear threats – whether from individual states, alliances of states, terror-group adversaries, or even state-terror group "hybrids" – must be symmetrically countered. The invariant core of any such assumption is the following seemingly plausible proposition:
A particular state's deterrent credibility must be directly proportionate to pertinent enemy threats.
At first, this "symmetry hypothesis" appears to make perfect sense. But authentic strategic truth can sometimes be "recalcitrant" or counter-intuitive. Moreover, because virtually all of the Israel-related scenarios or cases in point are effectively sui generis, or without any determinable precedent, nothing of true scientific value can ever be extrapolated concerning usable probabilities.
It follows, inter alia, that any meaningful assessment of hypotheses regarding "asymmetrical deterrence" and Israel's security must always be limited to formal deductive analysis. This indicates, among other things, assessments that are effectively devoid of tangible empirical content, yet are still defined by appropriately stringent standards of internal consistency, logical interconnectedness, and conspicuously dialectical thinking.
How to begin? A good place would be with the "gray area" of future enemy non-nuclear threats that are nonetheless unconventional. Most obvious, in this connection, would be credible enemy threats of biological warfare and/or biological terrorism. While assuredly non-nuclear, biological warfare attacks could conceivably also produce grievously injurious or even near-existential event outcomes for Israel.
In principle, at least, Israeli policies of calibrated nuclear reprisal for certain BW attacks could exhibit significant deterrent effectiveness against three of the four above-mentioned adversarial categories. Such policies would be inapplicable, prima facie, against threats from those terror groups functioning without any recognizable state alignments. In such expectedly residual cases, Israel – then plainly lacking operational targets suitable for nuclear ordnance – would need to "fall back" upon the more usual arsenal of counter-terrorist methods and options.
This tactical retrogression would be required even if the particular terror group involved (e.g., Sunni ISIS or Shiite Hezbollah) had already revealed plausible nuclear threat capabilities.
What about those conventional enemy threats that would involve neither nuclear nor biological attack, but were still prospectively massive enough to produce existential or near-existential consequences for Israel? On its face, it seems that in such cases, a would-be conventional aggressor could still reasonably calculate that Jerusalem might actually make good on certain of its decipherable nuclear deterrent threats. Here, however, Israel's nuclear deterrent threat credibility could be largely dependent upon an antecedent doctrinal shift from "deliberate nuclear ambiguity" (the so-called "bomb in the basement") to more overt "nuclear disclosure."
Why? The correct answer must hinge on Israel's presumed operational flexibility. More specifically, in the absence of any prior shift away from deliberate ambiguity, a would-be aggressor state might still not really understand or accept that the Jewish State already had available to it a sufficiently broad array of graduated nuclear retaliatory responses. Of course, in the presumed absence of such an array, Israeli nuclear deterrence could be correspondingly diminished.
As a direct consequence of its presumptively diminished nuclear ambiguity, Jerusalem could signal its relevant adversary or adversaries that Israel would wittingly cross the nuclear retaliatory threshold to punish any acts of existential or near-existential aggressions. Using more expressly military parlance, Israel's shift to apt forms of nuclear disclosure would then be intended to ensure "escalation dominance."
In any such dynamic and complex scenario, the nuclear deterrence advantages for Israel of moving beyond traditional nuclear ambiguity would lie in the compelling signal it is then able to send to particular foes. This signal warns that Jerusalem would not necessarily be limited to launching retaliations that employ only massive and disproportionate levels of nuclear force. A timely Israeli move from ambiguity to disclosure – as long as this doctrinal move were suitably nuanced and incremental – could substantially improve Israel's prospects for deterring large-scale conventional attacks with more consciously "tailored" nuclear threats.
Finally, it is well worth noting that these stipulated nuclear deterrence benefits could extend to certain Israeli threats of nuclear counter-retaliation. If, for example, Israel should sometime consider initiating a non-nuclear defensive first-strike against Iran, a preemptive act that would persuasively represent "anticipatory self-defense" under authoritative international law, the likelihood of suffering any massive Iranian conventional retaliation might then be diminished. In essence, by following a properly prepared path from deliberate nuclear ambiguity to nuclear disclosure, Jerusalem could expectedly upgrade its indispensable deterrence posture vis-à-vis both nuclear and non-nuclear threats.
Ultimately, Israel's nuclear deterrent must be oriented toward dominating escalation at multiple levels of conventional and unconventional enemy threats. For this to work, Israeli strategic planners must bear in mind that all future operational success will depend upon prior formulations of suitable doctrine, or strategic theory. In the final analysis, it cannot be overemphasized; strategic theory is a "net."
Only those who cast, can catch.
Louis René Beres, a frequent contributor to Israel Defense, is Emeritus Professor of International Law at Purdue. He is the author of many books and articles dealing with nuclear strategy and nuclear war.