I have resigned from the cabinet because I believe that a fundamental principle of Labour's foreign policy has been violated. If we believe in an international community based on binding rules and institutions, we cannot simply set them aside when they produce results that are inconvenient to us.
I cannot defend a war with neither international agreement nor domestic support. I applaud the determined efforts of the prime minister and foreign secretary to secure a second resolution. Now that those attempts have ended in failure, we cannot pretend that getting a second resolution was of no importance.
In recent days France has been at the receiving end of the most vitriolic criticism. However, it is not France alone that wants more time for inspections. Germany is opposed to us. Russia is opposed to us. Indeed at no time have we signed up even the minimum majority to carry a second resolution. We delude ourselves about the degree of international hostility to military action if we imagine that it is all the fault of President Chirac.
The harsh reality is that Britain is being asked to embark on a war without agreement in any of the international bodies of which we are a leading member. Not Nato. Not the EU. And now not the security council. To end up in such diplomatic isolation is a serious reverse. Only a year ago we and the US were part of a coalition against terrorism which was wider and more diverse than I would previously have thought possible. History will be astonished at the diplomatic miscalculations that led so quickly to the disintegration of that powerful coalition.
Britain is not a superpower. Our interests are best protected, not by unilateral action, but by multilateral agreement and a world order governed by rules. Yet tonight the international partnerships most important to us are weakened. The European Union is divided. The security council is in stalemate. Those are heavy casualties of war without a single shot yet being fired.
The threshold for war should always be high. None of us can predict the death toll of civilians in the forthcoming bombardment of Iraq. But the US warning of a bombing campaign that will "shock and awe" makes it likely that casualties will be numbered at the very least in the thousands. Iraq's military strength is now less than half its size at the time of the last Gulf war. Ironically, it is only because Iraq's military forces are so weak that we can even contemplate invasion. And some claim his forces are so weak, so demoralized and so badly equipped that the war will be over in days.
We cannot base our military strategy on the basis that Saddam is weak and at the same time justify pre-emptive action on the claim that he is a serious threat. Iraq probably has no weapons of mass destruction in the commonly understood sense of that term - namely, a credible device capable of being delivered against strategic city targets. It probably does still have biological toxins and battlefield chemical munitions. But it has had them since the 1980s when the US sold Saddam the anthrax agents and the then British government built his chemical and munitions factories.
Why is it now so urgent that we should take military action to disarm a military capacity that has been there for 20 years and which we helped to create? And why is it necessary to resort to war this week while Saddam's ambition to complete his weapons program is frustrated by the presence of UN inspectors?
I have heard it said that Iraq has had not months but 12 years in which to disarm, and our patience is exhausted. Yet it is over 30 years since resolution 242 called on Israel to withdraw from the occupied territories.
We do not express the same impatience with the persis tent refusal of Israel to comply. What has come to trouble me most over past weeks is the suspicion that if the hanging chads in Florida had gone the other way and Al Gore had been elected, we would not now be about to commit British troops to action in Iraq.
I believe the prevailing mood of the British public is sound. They do not doubt that Saddam Hussein is a brutal dictator. But they are not persuaded he is a clear and present danger to Britain. They want the inspections to be given a chance. And they are suspicious that they are being pushed hurriedly into conflict by a US administration with an agenda of its own. Above all, they are uneasy at Britain taking part in a military adventure without a broader international coalition and against the hostility of many of our traditional allies. It has been a favorite theme of commentators that the House of Commons has lost its central role in British politics. Nothing could better demonstrate that they are wrong than for parliament to stop the commitment of British troops to a war that has neither international authority nor domestic support.
· Robin Cook was, until yesterday, leader of the House of Commons
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