Two years is an age in politics. Who would have imagined that on the second anniversary of the invasion of Iraq, increasing numbers of US troops would still be embroiled in trying to subdue and pacify a population largely resentful of foreign occupation, spending $4 billion dollars every month in the process, and with no end in sight to its involvement. Furthermore the so-called "coalition of the willing" is gently unravelling as popular opinion prepares to wreak an electoral vengeance on governments that insist on maintaining troops in Iraq. Ukraine and the Netherlands are in the process of withdrawing their troops and Italy has announced that it will do the same. Bulgaria will also pull its troops out by the end of 2005.

Six weeks after the elections there is still no administration in place and bombings, kidnappings nad killings continue. As a fully paid up member of the "I told you so brigade" I take some grim satisfaction in the fact that the only organisation prepared to take on the dangerous and thanklesstechnical back-up for those elections was - you guessed - the United Nations, the selfsame body that was excoriated by the Americans for being soft on terrorism by refusing to roll over and endorse President George W Bush's and Tony Blair's war to replace Saddam Hussein.

Paradoxically, if the UN were not important, and if the Security Council was not crucial to international legitimacy, Britain and the USA would not have abandoned the quest for a second resolution authorising force against Iraq, the moment they realised it would not receive majority support. Hans Blix and his UN inspection team are also paid up members of the "I told you so brigade." All Colin Powell's Security Council histrionics on weapons of mass destruction can now be seen as a miserable attempt to dredge up a reason other than regime change for invading Iraq. With each week that passes the benefits of the collective wisdom of the UN, rather than the gungho adventurism of a world superpower are apparent.

The fact is that, for all its manifold faults, the UN survives because it is essential. It encompasses a vast and complex commitment to difficult "frontline" work. But, despite the ease with which one could list the innumerable agencies and the solid work of its many programmes it would not dispel the doubts of the cynics nor the suspicions of the xenophobes. For them its political failures are evidence of its inutility and its successes are warnings of the dangers of a supranationalism. The UN simply cannot win. Either way it is criticised.

The whole idea of the UN, and its continued existence, relies on a single gigantic compromise: that, for the sake of a potential benefit, or, occasionally, a common interest, the nations of the world will swallow their entrenched enmities, turn a blind eye to their myriad differences, and meet on common ground. From this one over-arching idea scores, if not hundreds, of lesser compromises flow. If there was no tacit acknowledgement of the necessity for such an arrangement the UN would never have survived the sixty years of its existence.

A major obstacle for the UN is that it is enfeebled by its lack of resources. Many of its members are in arrears with their designated contributions and for years the worst offender was the United States. One had the unedifying spectacle of the USA criticising the UN for its ineffectiveness whilst at the same time denying the resources required to make it effective. UN operations are expensive - the peace-keeping mission in the Democratic Republic of the Congo, for instance, costs US$750 million per year. It is certainly a large sum but it can easily be put into context by the realisation that the current situation in Iraq is costing the USA more than five times that each month!

Those of us who call ourselves internationalists and "world citizens" must shoulder some of the blame for the state of the UN. We have tended to be far more idealistic than practical in our thinking, assuming too readily that borders could be rubbed off the map and that everyone would live happily ever after. The politics of international relations are singularly complex, and much more intellectual rigour is needed to define the role of the UN in relation to regional developments - not just the European Union, but also initiatives such as ECOWAS (Economic Community of West African States) and OAS (Organisation of American States). Globalisation of the economy demands a globalisation of politics and the way forward can only be incremental, region by region. The UN has already begun to cede some of its responsibilities to regional organisations and this trend seems bound to continue.

The UN's labyrinthine bureaucracy is notorious and I have many times seethed with frustration trying to cope with it, in order to meet electoral deadlines, in countries from Suriname to Malawi. But whereas that bureaucracy inevitably hampers its effectiveness, the UN's problems are much more fundamental. Far too much is expected of the UN, and the tasks it is asked to take on are, by definition, tasks that others have failed to resolve. Its failure to prevent the Rwandan genocide in 1994 and the virtual impotence of the Security Council to prevent the continuing murderous assaults on the people of the Darfur province of Sudan, are indeed horrendous but without an acceptance that substantial forces can be on permanent standby - whether under the UN or under a regional command, as with ECOWAS in Sierra Leone - and significant financial resources available to support them, it is difficult to see how such tragedies can be averted.

Proposals to reform the UN, put forward last December by a high powered committee appointed by Kofi Annan, are based on a forthright analysis of the problems, both internal and external. In particular it proposes new definitions of legitimacy for the use of force, including pre-emptively, to counter terrorist threats, as well as to protect citizens from their own governments.

It remains to be seen whether Kofi Annan and his colleagues have the authority to push through the changes demanded but, if not, the looming presence of the USA as the world's only superpower, prepared to act unilaterally in its own interests, will increasingly overshadow every crisis and seek to dominate every conflict. President Bush has shown what his administration thinks of the UN by appointing John Bolton as the US Ambassador to the UN - a man who is on record as saying, "There is no such thing as the United Nations." I know whom I feel safer with - we need a strong United Nations, w