For decades the Middle East has been characterized by a reality of strategic parity. At one pole was the conventional military power of the Arab countries, and at the other was Israeli nuclear ambiguity or opacity. Israel has never revealed officially what it does at the Dimona nuclear research center. It allowed the Arabs to guess. Speculation deters.

But nuclear ambiguity was not created to counter Arab conventional power. In aggregate the Arab states can field a military coalition that comprises tanks, aircraft and artillery in quantities several-fold in excess of those of Israel. The supply of western arms to Arab countries has also reduced Israel's qualitative edge. To this we must add Israel's geographic dimensions, which render it an even more vulnerable state. All these have, as noted, been balanced by Israel's nuclear ambiguity.

Within a few short years, this balance is liable to change dramatically. As early as 2004, Iran will apparently reach a "point of no return": that phase in its nuclear weapons development wherein it is no longer dependent on the external supply of technology and can construct a bomb using its own resources. Iran already has operational missiles capable of delivering a nuclear bomb to a range of 1,300 kilometers; missiles with ranges of 2,000 and 5,000 kilometers are being developed.

The International Atomic Energy Agency recently confirmed that for 18 years Iran has been secretly developing nuclear weaponry. This program coincides with the strategy of the ayatollahs' regime as defined by Iranian Minister of Defense Ali Shamkhani in a speech on "Revolution Day" in August 1998: the Iranian strategic objective is to defend Muslim minorities and organizations anywhere on earth. In practical terms, Iranian nuclear missiles will enable the theocratic regime in Tehran to threaten any country that refuses to bow to its own domestic Islamic extremists. The immediate victims of Iranian nuclear blackmail will be the Gulf states, followed of course by Israel, and then by the rest of the world.

From Israel's standpoint, this means a daily existential threat. Most of Israel's economic and intellectual assets are located in a narrow coastal strip between Haifa Bay and Ashkelon. Two nuclear bombs could render Israel a burned-out third world state. Such a threat would seriously affect national morale, people's readiness to build their futures in the country, and the key decisions taken by Israeli governments. Even today the government of Israel is making decisions that it would previously never have considered, because tens of thousands of Iranian missiles and rockets are deployed in southern Lebanon, where they threaten a million and a quarter Israelis in the north of the country. Acquiescence in Lebanese pumping of the Hatzbani waters and de facto annexation of the Israeli village of Ghajar are examples of such decisions. Against this backdrop it is easy to imagine how an Iranian nuclear threat would affect decisionmaking in Jerusalem.

Clearly, too, an Iranian nuclear weapon will push Saudi Arabia to obtain similar weaponry to balance Iran's threat. The Saudi investment in the Pakistani nuclear project encompasses a Pakistani commitment to deliver to Saudi Arabia, upon the latter's request, a Pakistani nuclear warhead for mounting on the Chinese-made surface-to-surface missiles that the Saudis possess.

Only a campaign of massive and immediate political pressure, accompanied by tough economic sanctions and led by the United States, could delay the progress of the Iranian nuclear project. Iran's current strategy is thus to play for time, through deception and deceit.

If the US insists on not being deceived, and maintains pressure on the president of Russia to block the Russian assistance that is so necessary to the Iranians, then there is a chance that the pace of development will be slowed. Any delay is for the good. Israel must act at the diplomatic level to ensure that the US deploys all of its political and economic power in this regard.

If this does not happen, and Iran approaches the point of no return, Israel will confront several tough alternatives. Acquiescing in the possession of nuclear weapons by those who vow to erase Israel from the map is not one of those options.