When all other avenues have been tried, war does sometimes become the necessary last resort. To flinch from it becomes far more dangerous than to accept its dread inevitability, as we learnt between 1933 and 1939.
Tony Blair deserves not abuse but full support for his courage; he knows that allowing President Saddam to survive in power with his weapons of mass destruction is far, far more dangerous than removing him now.
The French would like us to believe we are rushing into war. Nonsense. For 12 years President Saddam has defied the United Nations demands that he hand over and destroy his biological, chemical and nuclear weapons programmes. They have been "12 years of humiliation for the United Nations" in Jack Straw's words. Twelve years in which the international community has failed to enforce its own laws against one of the vilest dictators on earth.
This is a man who has caused the deaths of more than a million Muslims, used chemical weapons against the Iranians and the Kurds, invaded and terrorised Kuwait, tried to murder a former US President, been linked to the 1993 attempt to blow up the World Trade Centre, used Stalinist methods of terror on his own people, and made the most diabolical attempt to create the most deadly weapons known to Man in defiance of the world.
And yet the French and others say he needs more time? This is not a joke, it's a mockery of any hope for a system of collective security. Those who plead for more time are, in fact, encouraging President Saddam, thus making war more likely, and undermining (perhaps fatally) the international system on which we all depend.
Remember Resolution 1441, whose every word the French co-authored and which the Security Council unanimously approved on 8 November last year? That gave the Iraqi dictator a "final opportunity" to obey the 16 other binding resolutions he had ignored since 1991, and to disarm fully, completely and immediately. Inspectors were to be allowed back into the country from which he had illegally barred them since 1998. They were not there to search for weapons but to verify his disarmament. U2 surveillance flights under UN control were to resume. Iraqi scientists were to be interviewed privately, or even abroad.
None of this has happened . Instead, Iraq's response to 1441 has been complete contempt of its legal requirements. In place of disarming, it has published a blatantly false declaration of its WMD, forced the inspectors into wild-goose chases in which (to mix a metaphor) they are having to look for noxious needles in a haystack the size of France, made it all but impossible for its scientists to give unmonitored interviews to the UN, and blocked, until recently, U2 overhead surveillance flights.
It seems that until the last few weeks, President Saddam did not believe the US and UK and their other allies were serious. Now with more than 200,000 US and other troops on his borders, he may realise the threat to him is real.
That would explain his reluctant, last-minute striptease, agreeing to destroy at least some of his Al Samoud 2 missiles, which we have long known he had illegally modified. But do not be deceived. This is the equivalent of removing an outer garment, nothing more. The Iraqi dictator's posture is the same now as it has been for the past 12: give up what he cannot conceal and keep hiding the rest.
Where, for example, are the al-Hussein missiles, which have a far longer range? Where are the 8,500 litres of anthrax he had in 1998, the huge stockpiles of VX gas, of which a single drop on the skin can kill? The excitement about the partial surrender of the Al-Samouds has eclipsed all concerns about such still well-hidden weapons.
I recently went to see Ken Pollack, the author of The Threatening Storm: The Case For Invading Iraq. Pollack used to deal with Iraq on President Bill Clinton's national security council. His book has been praised for setting out clearly and coolly the choices the world has faced and still faces with President Saddam.
Pollack is no cheerleader for the Bush Administration, but he does applaud the fact that they have finally grasped this dangerous, painful nettle.Why have they done it? "I think that after 9/11 they were deathly afraid of the combination of weapons of madestruction and terrorists."
But is there not a danger that in the final corner, the Iraqi leader might hand over some of his chemical or biological agents to terrorists? Pollack agreed that was possible. "But at the end of the day, Saddam with nuclear weapons is far worse. And the fact that we think Saddam might make such a deal with terrorists is surely another argument for saying he poses an unacceptable danger."
Asked if extended and expanded "containment", as proposed by the French, was an answer, Pollack said: "No. The only reason we are getting any slight co-operation from Saddam now is because of the massive troop build-up. But they can't stay there indefinitely, and if Saddam and his sons remain in power we are talking 20 years. Would France be willing to send 250,000 troops there to replace us? No."
Saddam has always been further ahead on his WMD programmes than we thought. In the late Eighties, US intelligence thought Iraq was five to 10 years from building a nuclear weapon. The International Atomic Energy Authority thought he had no such programme. In 1991, the IAEA's inspectors found he was lethan two years from producing a weapon. In the Nineties, the inspectors found important weapons mostly because of information from defectors. Since the inspectors were compelled to leave in 1998, new defectors have said that President Saddam has started a new nuclear bomb programme with new methods of concealing it.
Terry Taylor, a British former senior weapons inspector, now in Washington with the International Institute of Strategic Studies, says that in 1998 "Saddam had every-thing to make a nuclear weapon except the fissile material. We don't know if they have yet got fissile material, enriched uranium."
But we do know it is around. A few months ago, some was intercepted on the Bulgarian-Turkish border. And, Mr Taylor points out, President Saddam has still not accounted for 35 tons of highly sophisticated HMX explosive, crucial to any implosion device (and the IAEA inspectors have reported it missing).
We simply do not know how close to a nuclear bomb he now is. But if he gets one, he has said he wants to turn Iraq into a "superpower" that will dominate the Middle East and "liberate" Jerusalem.
Remember, we are dealing here with a psychotic mamurderer who is also an insane optimist. Just as President Saddam thought he could get away with the invasion of Iran, and that of Kuwait, so he now believes he can continue to ignore the established law of the world embodied in 1441 and all the other resolutions. By throwing the inspectors a scarf and a coat, he thinks he can encourage and confuse the worldwide audience while keeping his real crown jewels - biological, chemical, nuclear - concealed.
President Saddam's victory in acquiring nuclear weapons would encourage others, such as North Korea, to believe there are no restraints any more. It would be a total defeat for the United Nations and would risk far worse conflagration. It is not a risk any responsible leader can take. Prime Minister Tony Blair understands that.
I hope there will be another UN resolution, not a second, as the French claim, but a 17th. It will help Mr Blair and other leaders such as Spain's Prime Minister, Jose Maria Aznar, who are brave enough to say what they know to be right even though it is unpopular. But the Security Council has already decided President Saddam must face "serious consequences" if he fails to disarm; the international legal authority for military intervention already exists.
I understand the concerns of those people who genuinely fear this war. But when Mr Blair says future generations would not forgive us if we fail to deal with this threat now, he is right. The costs of war now are frightening, but the costs of allowing the Iraqi dictator to continue to terrorise the Iraqi people and the world are far worse.
There is still a way out: President Saddam's overthrow or exile in the face of the massive pressure the US, Britain and their allies have mounted. If the Security Council was still united, instead of being tempted down the low, apparently easy road by French pied pipers, such an outcome would be more likely. I hope it still happens. But if it does not, there will be no alternative. We cannot walk away yet again while this man conspires to build weapons which he thinks will make him untouchable and with which he could kill millions of people.