To deter an Iranian first-strike attack, or even a post-preemption retaliation, Israel must first be able to prevent a rational adversary in Tehran, by threat of an unacceptably damaging reprisal or counter-reprisal, from deciding to strike. Security would be sought by convincing the would-be attacker (an irrational Iranian enemy would pose an altogether different problem) that the costs of any considered attack on Israel would necessarily exceed its expected benefits.
Here, assuming Iran would (1) always value self-preservation most highly and (2) always choose rationally between alternative options, Tehran would refrain from any attack upon a Jewish state that was believed willing and able to deliver an unacceptably destructive retaliatory response.
With Israel’s strategic nuclear doctrine and missiles kept locked away in the “basement,” an Iranian nuclear enemy could sometime conclude, rightly or wrongly, that a first-strike attack, or post-preemption reprisal, would be rational and cost-effective. Were relevant Israeli doctrine made more plainly obvious to Iranian decision-makers, however, Israel’s nuclear forces could then more appropriately serve their existential security function.
Any continued ambiguity over nuclear doctrine could also create the injurious impression of an unwilling Israel. Conversely, a doctrinal movement toward some as-yet-undetermined level of disclosure could heighten the impression of an Israel that was, in fact, willing to follow-through on its recognizable nuclear threats.
There are utterly persuasive connections between a more open strategic nuclear doctrine and Iranian perceptions of Israeli nuclear deterrence. One such connection centers on the relation between greater openness, and perceived vulnerability of Israeli strategic nuclear forces to preemptive destruction. Another pertinent connection concerns the relation between greater openness, and the perceived capacity of Israel’s nuclear forces to penetrate Iran’s active defenses.
Doctrinal openness, carefully articulated, could represent a rational and prudent option for Israel, to the extent that enemy states were made appropriately aware of Israel’s relevant nuclear capabilities. The determinable operational benefits of Israeli doctrinal openness would then accrue from deliberate flows of information about such vital matters as dispersion, multiplication, and hardening of strategic nuclear systems, and also about certain technical features of strategic nuclear weapon systems.
Above all, meticulously controlled doctrinal flows of information could serve to remove any lingering enemy state doubts about Israel’s strategic nuclear force capabilities.
One final point about Israeli nuclear disclosure still needs to be made. In the very unlikely event that Prime Minister Netanyahu decides, together with his security cabinet, to launch an eleventh-hour preemption against Iran, Israel could require a plainly convincing counter-retaliatory nuclear option. In other words, Israel could then need a recognizable capacity to deter Iran from launching any substantially damaging reprisals.
Because selective increments of nuclear disclosure might best persuade Iran that Israel’s nuclear weapons were distinctly usable, survivable, and penetration-capable, this deterrent capacity could be improved by prior Israeli movements away from deliberate nuclear ambiguity.