JERUSALEM -- Of the three countries that composed the axis of evil -- Iraq, Iran and North Korea -- without a doubt it is Iran that represents a double axis of evil: It serves as the largest terror nucleus in the Middle East, and also possesses a selection of nuclear resources -- plutonium, enriched uranium and centrifuges. Iran is right behind North Korea in realizing its nuclear capabilities, involving a huge financial investment, in a country rich in oil, but whose citizens are condemned to poverty.

Americans are just now beginning to understand the dangers posed by a nuclear-armed Iran. A recent Washington Post/ABC poll found that 56% of Americans endorse the use of U.S. military action to prevent Iran from developing nuclear weapons, while just 38% opposed it. By contrast, we Israelis have always understood the dangers posed by a nuclear Iran, a state that has long backed terrorist attacks against our people.

In Israel, Iranian fingerprints can be found on the operations of a number of terror organizations. The Iranians fund, arm and train Hezbollah, a terror organization par excellence; around 100 officers of the Iranian Republican Guard are in Lebanon, helping Hezbollah prepare for, and put into effect, acts of terror. They train Hezbollah in the skills of launching the 10,000 rockets that they put at their disposal. They give Hamas and Islamic Jihad a hand in carrying out acts of terror inside Israel. One example of Iran´s involvement in terrorist activities is Argentina, as was disclosed by the Argentinean government in its investigation of the bombing of the Jewish community building in Buenos Aires.

The International Atomic Energy Agency recently published its findings that Iran was in breach of the control mechanism to which it had agreed and had taken alarming steps forward toward realizing its nuclear ambitions. Iran refrained from reporting the procurement of nuclear substances, their proces sing and storage, and barred effective inspection tours of its nuclear installations. While Tehran has since said it would increase its "cooperation" with the IAEA, it has insisted on continuing its uranium-enrichment program.

It is frightening to imagine nuclear weapons in the hands of Ayatollah Ali Khamenei, Iran´s supreme religious leader, and a theocracy that publicly endorses the assassination of people whose ideas contravene its beliefs. The death sentence passed on Salman Rushdie, without a trial and with no criminal foundation, is an indelible mark of Cain on the forehead of the Iranian ayatollahs. And the persecution of Rushdie as performed by this ruthless regime, is now perpetrated against the "Great Satan´ -- the United States -- and the "Small Satan" -- Israel -- as they call for its annihilation. In a very real sense their crusade is against a collective Salman Rushdie.

There is no greater danger than the conjunction of an evil regime with nuclear capabilities. Imagine how Europe would have fared had Hitler succeeded in developing nuclear weapons ahead of the United States. A state run by ayatollahs armed with nuclear weapons -- the same ayatollahs who proclaim fatwas against Western thinkers and harbor and sponsor terror organizations -- represents a new level of danger that threatens the world at large.

In the wake of the recent wars in Afghanistan and Iraq, the question now is what to do with Iran? Clearly, a third war is no simple matter. The war against Iraq was engaged after Iraq had breached, time and again, the resolutions of the U.N. Security Council. In Iran´s case, the appropriate and immediate steps to be taken should include serving Tehran with a collective warning by the relevant parties -- including the U.S., the U.N., Europe and Russia -- to desist from terror activities and stop its race for weapons of mass destruction.

Unfortunately, the world has not been in agreement on the urgency of the threat posed by a nuclear Iran. Russia believes -- or more correctly, believed until now -- that Iran was ready to comply with effective inspections of its nuclear installations. Europe, including France and Germany, felt that the accusations against Iran were exaggerated. The U.S. understandably decided to deal with Afghanistan and Iraq before tackling the issue.

A common position on Iran´s nuclear aspirations was therefore never reached. And Iran enjoyed the fruits of this ambivalence, relying on a lasting divisiveness. Indeed, should this political polarization continue, and if Iran decides to move forward on its dual course of proliferation of terror and weapons of mass destruction, we might find ourselves at a point of no return. Therefore, to avoid another war, every effort must be made, and all available resources used, to prevent such an eventuality from materializing.

The U.S., Europe, Russia and the U.N. must formulate a united policy concerning Iran. The ayatollahs in Tehran need to be warned that it they are crossing the tolerance threshold of the world -- a world that will not tolerate the existence of terrorists with weapons of mass destruction. Clearly, as long as Iran is under the impression that it can toy with an indecisive world -- and deepen the divide -- it will provide endless denials, while at the same time intensifying its efforts to realize its sinister goals. Such a situation would be intolerable. This was the course adopted by Saddam Hussein. He walked the tightrope of differences of opinion between the U.S. and the EU until the diplomatic option collapsed, leaving room for an only course of action -- the military one.

A joint warning, backed by a threat of economic sanctions, is the best possible track to save Iran from its own folly, and avert the need to resort to military action again. What is needed right now is a resolute and united political strategy, to get rid of a terrible threat that is growing more menacing by the day.

Mr. Peres, a former prime minister of Israel, is chairman of the country´s Labor Party. (Copyright © 2003 Dow Jones & Company, Inc. 06/25/03)