Imagine how dangerous, how potentially destabilizing a military strike against Iranian nuclear facilities could be to the region and the world. And yet any such attack would be infinitely less dangerous and less destabilizing than allowing nuclear bombs to fall into the mullahs' hands. Now, with the civilized world at a crossroads, imagine being able to prevent both such chilling scenarios by making tough yet wise decisions in the next weeks and months. That was the message Prime Minister Ehud Olmert brought to the annual policy conference of the American Israel Public Affairs Committee on Tuesday: "We must stop the Iranian threat by all possible means. Each and every country must understand that the long-term cost of a nuclear Iran greatly outweighs the short-term benefits of doing business with Iran." The urgency of Iran was probably the reason Olmert travelled to Washington to meet with President George W. Bush so soon after seeing him in Jerusalem, and despite his political travails at home. LAST WEEK the International Atomic Energy Agency essentially announced that Teheran was stonewalling the agency. And still Mahmoud Ahmadinejad continues to travel around the world - on Tuesday he was in Rome for a UN food summit - spewing hatred and talking genocide. Israel, he said, is "doomed to go." This from a leader who has repeatedly threatened to wipe Israel off the map, and who last month referred to the Jewish state as a "stinking corpse... on its way to annihilation," which has "reached the end like a dead rat." To their credit, both Italian Premier Silvio Berlusconi and Pope Benedict XVI refused to meet Ahmadinejad. THE IRANIANS know they are playing with fire. Defense Minister Mostafa Mohammad Najjar has warned that "any attack on Iran would... result in painful consequences for the attacker... I believe the Zionist regime degraded itself when it proved powerless against Hizbullah - to such an extent that it would never be able to bear the first response of Iran." Such saber-rattling accompanies Iran's gloating in the knowledge that it will very soon reach the point of no return in its acquisition of nuclear weapons. Teheran continues unabated to build centrifuges (Ahmadinejad has boasted of 3,000 already in operation), enrich uranium, test high-explosive triggers for nuclear devices and redesign the nose-cone of the Shahab-3 rocket to accommodate nuclear warheads. At this critical juncture, as time runs out, the reasons why the Iranians must not get the bomb bear repeating. â€¢ Iran acts as a leading sponsor of terrorism in the world. It trains, finances, and equips Hamas, Hizbullah and extremists in Iraq. â€¢ Iranian proliferation of nuclear technology to terrorist groups is a terrifyingly real possibility. â€¢ Iran is not like the former Soviet Union. It is a fundamentally unstable regime. There are power struggles between the presidency, the parliament, the Revolutionary Guards and the office of Supreme Leader Ayatollah Khamenei. The country's foreign polices are often dangerously erratic. â€¢ Finally, even the doctrine of mutual assured destruction (MAD) that governed the Cold War does not necessarily apply to a regime ruled by religious fanatics for whom martyrdom may well be not a deterrent, but an inducement. WHAT THEN is the civilized world to do? It must pressure the Iranian leadership - relentlessly - by imposing severe political, social and economic sanctions. It must freeze assets and outlaw business with the Central Bank of Iran. It must bar Iranian airliners from landing at major airports. Iranian leaders must be made personae non grata at international forums. The commonwealth of nations has to know that if it does not change course and continues with the modest sanctions now in place, Iran is on track toward nuclearization. Brazenly, Teheran has defied successive Security Council resolutions calling on it to suspend its uranium enrichment - including a round of sanctions approved by the council in December 2006, and a "tougher" round authorized three months later. It has rejected European offers of generous economic incentives, including support for a civilian nuclear energy program. In his AIPAC address the premier spoke for all Israelis, when he declared: "The international community has a duty and responsibility to clarify to Iran, through drastic measures, that the repercussions of its continued pursuit of nuclear weapons will be devastating."