Like Chris Skinner, I’m deeply skeptical about Sam’s proposition that Israel could improve its own security by resorting to unilateral nuclear disarmament, as a means of resolving the crisis over Iran’s nuclear aspirations.

The logic of Sam’s argument appears to rest on the dubious assumption that Iran’s bid for nuclear weapons – or at least the ability to quickly acquire them – is motivated almost entirely by a desire either to deter an Israeli nuclear attack or prevent itself from falling victim to Israeli coercion. Should it no longer have to confront these threats, the argument goes, Iran would have no requirement for nuclear weapons and, consequently, neither would its Arab neighbours.

Of course, divining Teheran’s intentions is very difficult. But it’s not hard to imagine that one of the primary drivers of the Iranian nuclear program is to redress Israel’s regional nuclear primacy and create a nuclear balance vis-à-vis Israel, which is more congenial to Iran’s interests. Nevertheless, can we – or moreover, could Israel – so readily discount a range of other possible motivating factors, such as hegemonial ambition, prestige, or deterrence against American conventional or nuclear attack — all of which would remain pertinent to Iran, despite Israeli nuclear disarmament? I think not.

But even if we do assume, as Sam does, that Israel’s nuclear weapons are the problem, it does not follow that Israeli disarmament would necessarily assuage Iranian fears, or sufficiently alter Tehran’s calculations in ways that would make its pursuit of at least advanced enrichment capabilities, if not actual weapons, much less likely. If, after disarmament, the retention of a very advanced threshold capability could continue to assure Israel of its strategic security, as Sam argues, it seems unrealistic to expect that the same process might disproportionately reduce Iranian insecurity. The zero-sum nature of the competition is such that, while Israel might no longer have nuclear weapons, in relative terms, its decisive nuclear edge would continue to fuel Iran’s anxiety, providing it with an ongoing rationale for proliferation.

In dealing with the Iranian nuclear crisis, Sam is right to say that Israel may well have to consider unpalatable options. But unilateral disarmament — because it poses unreasonable costs and risks, and is so unlikely to be effective when the stakes are so high – will never be one of them.