By Ronen Bergman

Israel feels existentially threatend by the Iranian nuclear program. As there is little evidence that pressure and negotiations can deter Tehran from pursuing nuclear weapons, a preemptive military strike against Iran's nuclear facilities becomes more probable.

Ronen Bergman is senior political and military analyst for Yedioth Ahronoth, Israel's largest circulation daily, and the author of "The Secret War With Iran".

Some time ago, the Director of the Mossad summoned the CIA's station chief in Tel Aviv to an urgent meeting at his home. In an encounter the director later described as "the most difficult meeting I have ever had with a representative of a foreign intelligence service," he laid out before his visitor the arguments in favor of a preemptive Israeli strike. The situation was grave, he explained, and time was not working in Israel's favor. Personally he regretted that Israel had not yet taken action. Yes, a few rules would have been broken, but the outcome would have been positive for both the US and Israel.

The American's response was a confusing mix of threats and encouragement, and the Israeli government decided to send the director to Washington to find out from the US Secretary of Defense what action the Administration was willing to tolerate.

These events took place 40 years ago on the eve of the Six Day War. The Director of the Mossad was Major General Meir Amit, the CIA station chief was John Hadden, and the Secretary of Defense the Director met with in Washington was Robert McNamara.

When Amit informed McNamara that Israel could no longer tolerate Egypt's military build-up, the Secretary's response was,"I hear you very clearly." The Israeli government was satisfied with McNamara's laconic reply, and, confident that there would be no negative repercussions from the US, set in motion its military offensive. Less than a week later, the Middle East was at war.

Today, once again, the question of the extent of Washington's opposition to Israeli military action looms large, this time in the context of Iran's nuclear aspirations. And, arguably, more is at stake today for both Israel and the US than was on the eve of the Six Day War. Given that Barack Obama is viewed by many observers as being less inclined than any of his recent predecessors to acquiesce to Israeli action that could, at a bare minimum, seriously disrupt his foreign policy agenda, the decision that the Israeli government faces whether or not to attack Iran has become a high-stakes gambit in terms of Israel's relations with its ally. And the cost that Israel might have to pay for getting this particular calculation wrong may well be punitive. Consequently, as Israel is hardly going to act in the absence of a green light from Washington - which, as of this writing, seems unlikely to be given any time soon - Israel will not attack.

"When Israel's survival is at stake, the country's leaders are willing to risk incurring Washington's wrath by going it alone."

This, at least, is the conventional wisdom, and indeed, members of the Israeli intelligence and diplomatic communities report that the question that was constantly on the lips of their European counterparts in the final days of the Bush Administration - is Israel going to attack Iran? - is rarely posed nowadays.

But the truth of the matter is that despite the fact that Washington's reaction has always been high on the list of strategic considerations of Israeli decision-makers, when Israel's survival is at stake, the country's leaders are willing to risk incurring Washington's wrath by going it alone, even keeping Washington out of the loop, if necessary. Such was the case, memorably, when Israeli Air Force bombers destroyed the Iraqi nuclear reactor outside Baghdad, in 1981, much to President Reagan's fury.

This truth seems to have been forgotten. To a certain extent, I suspect, this may be wishful thinking, especially on the part of European observers. More importantly, however, it seems to me that many foreign observers profoundly underestimate the importance of the memory of the Holocaust as one of the key engines that drive the Israeli political decision-making process.

It is hard to exaggerate the hold that the collective memory of the Holocaust still has on Israeli society 65 years after the liberation of Auschwitz. The shadow cast by the destruction of European Jewry has not been dispelled with the passing of the years. On the contrary, as new threats of physical annihilation have emerged, the centrality of the Holocaust to the modern Israeli experience has increased, and the lesson to be learned from the events of the past appears more relevant than at any time in recent decades.