Jerusalem is increasingly jittery that cracks are appearing in the nearly half-century-old US policy of upholding Israel’s right to maintain its “nuclear ambiguity,” following reports that Israeli nuclear capabilities are, for the first time, scheduled to be on the agenda of the International Atomic Energy Agency’s (IAEA) board meeting next month.

One diplomatic official said that the US has relayed messages to Israel that it will not let its nuclear position be harmed, but added that these assurances are being received with some skepticism amid the realization that while in the past the US has killed such discussions in international forums, this time it failed to do so.

If the US is slowly changing its policy, it would, one observer pointed out, run against commitments former US President George Bush gave former Prime Minister Ariel Sharon in his famous 2004 letter that paved the way for Sharon’s decision to disengage from Gaza.

In that letter, which dealt primarily with the Palestinian issue, and which Israel interpreted as a US acceptance of settlement blocs and a rejection of the Palestinian claim to a right of refugee return, Bush also wrote, “The United States reiterates its steadfast commitment to Israel’s security, including secure, defensible borders, and to preserve and strengthen Israel’s capability to deter and defend itself, by itself, against any threat or possible combination of threats.”

In private conversations, Sharon on numerous occasions said this represented a US obligation to prevent the international community, once it had de-fanged Iran’s nuclear ambitions, from then turning on Israelis’ reported nuclear capabilities.

Another observer, Emily Landau, a senior research fellow at the Institute for National Security Studies at Tel Aviv University and director of its arms control and regional security program, said the US was not assuming its role as the shield of Israel’s nuclear capabilities to the degree it had in the past.

Her comments, however, were in reference to the current Non-Proliferation Treaty (NPT) Review Conference at the UN, where Israel has been made an issue, and not to the IAEA draft which placed Israel as an item on the agenda.

Obama, according to Landau, has embraced the agenda of nuclear disarmament, as well as the norm of “equality” that is embedded in the NPT, meaning that all countries should be treated equally on the nuclear issue.

Having embraced that principle, Landau said, Obama has opened himself up for pressure from the Arab states and others who will say, “If you put pressure on Iran to stop nuclear development, why not Israel?”

“If you accept that all states are equal in the nuclear norm, you can’t give good arguments that could be used to counter this,” she said.

But such powerful arguments do exist, she said, such as that context matters: that the existential threat Israel lives under, as well as its very hostile neighborhood and the nuclear responsibility the country has shown over the years, must be taken into account when discussing the issue.

Landau said that if Israel altered its long-standing policy of nuclear ambiguity it would place itself on a slippery slope that would lead to intense pressure for it to disarm itself of its reported nuclear capabilities.

Landau said Israel should be less “gun-shy” in explaining its nuclear policy, and that it should clarify that what it supported in the Middle East was a weapons of mass destruction-free zone, not a nuclear weapons-free zone as advocated by Egypt.

One diplomatic official said the reason the Egyptians loudly push for a nuclear weapons-free zone, and not a zone free of all weapons of mass destruction, was simply because many Arab states have not signed onto treaties preventing chemical and biological weapons, even though they have signed the NPT.