Does John McCain have a "hidden agenda" to "kill the UN"? That's what the man who devised McCain's big set-piece foreign policy proposal says – and he's delighted it is sailing silently through the presidential election campaign towards success.

This story begins with a Republican presidential candidate who, despite the hype, doesn't seem to know much about foreign affairs. McCain recently talked at length about problems on the "Iraq/Pakistan border" – the countries are a thousand miles apart. Asked how to deal with Darfur, he mused about "bringing pressure on the government of Somalia". Uh – it's Sudan, Senator McCain. And he keeps expressing his desire to build up US relations with Czechoslovakia, a country that hasn't existed for 15 years.

But McCain does know one thing: he doesn't like the United Nations. He championed George Bush's appointment of John Bolton as US ambassador to the UN – precisely because Bolton scorns the UN as "irrelevant" and "a twilight zone". He even announced "there is no such thing as the United Nations". It was like appointing Marilyn Manson as ambassador to the Vatican. This is part of a long seam of thinking on the American right: they opposed Franklin D Roosevelt's spearheading of the United Nations as a fetter on American power, and have never been properly reconciled to it. Republican congresses have refused to authorise US dues to the UN – so there is now a backlog of $2.8bn (£1.5bn) outstanding.

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Yet McCain cannot oppose the UN outright – because the American people support it so passionately. Contrary to the yokel-myth, a typical opinion poll – by Global Public Opinion – just found that 64 per cent of Americans think the UN is doing a good job, compared to just 28 per cent who support George Bush. Some 72 per cent of Americans want the UN to play a bigger role.

So McCain has decided to build up an innocuous-sounding alternative called a "League of Democracies". It would be an alliance of countries the US labels democratic that can be used to legitimise US military actions. Charles Krauthammer, the conservative journalist who invented the plan, says: "What I like about it is, it's got a hidden agenda. It looks as if it's about listening and joining with allies... except the idea here, which McCain can't say but I can, is to essentially kill the UN. Nobody's going to walk out of the UN. There's a lot of emotional attachment to it in the US. How do you kill it? You create a parallel institution." Gradually – over decades – McCain hopes it would make the UN wither away.

Any response needs to start by admitting the UN has serious imperfections. Its structure is absurdly antiquated, with the permanent members of the Security Council frozen as the winners of the Second World War. The Human Rights Commission became an obscenity, offering places to Sudan and Saudi Arabia. There have been some horrible scandals in the past decade: UN peacekeepers who commit sexual abuse still aren't properly investigated, and some of them cut corrupt deals with the murderous Congolese militias they were supposed to stop. Even Kofi Annan's son Kojo has been involved in some dubious dealings.

Those of us who support the UN should be more outraged by these failures than anyone else. But the US government has also committed horrible abuses and been riddled with corruption – and nobody suggests the solution is to abolish it. No: it is to make it live up to its greatest ideals.

In addition to these real flaws, the UN is too often used as a bright blue punch-bag for any old complaint about the state of the world. For example, the UN is routinely blamed for not intervening in Burma, or Zimbabwe, or Georgia – but the UN has no army of its own; it is only as good as its members. Blaming the UN for these failures is like blaming Wembley Stadium when your football team loses a match.

The UN's positive achievements are almost never mentioned. It was the UN vaccination programme that abolished smallpox – an agonising disease that killed hundreds of millions of people – from the human condition. It was the UN that talked Kennedy and Khrushchev back from the brink when they were poised to incinerate the Earth.

The League would not even live up to its limited pro-democracy billing. If you study McCain's foreign policy statements, you find that for him "democracy" doesn't mean a free and openly elected leader. No: it means a leader who supports US demands.

You can see this if you compare McCain's reactions over the past fortnight to two different separatist movements: in Georgia and Bolivia. When it comes to Georgia, he says it is obscene for South Ossetians to secede from a country they never felt part of, and have never been directly ruled by. He orders the people there to decline the support of the foul Putin regime next door and remain glued to the government of Georgia, against their will, for the sake of keeping the country together. However, when it comes to Bolivia, he actively encourages separatism. The Bush administration – with McCain's support – has been lavishing cash on separatists in the gas-rich regions of this South American country in the hope that they will declare independence.

Why does McCain think separatism is "evil" in one part of the world, and "necessary" in the other? The answer lies in the ground. In Georgia, the democratic-but-dissident-bashing government lets the US control the oil and gas that pass through. In Bolivia, the impeccably democratic government of Evo Morales wants to control it on their own. Morales is asking US gas companies to pay their fair share, and using the proceeds to lift his own people out of poverty. For that, he is dubbed "authoritarian".

So there's McCain's definition of democracy: if you let us control your resources, you're a democracy. If you try to control your resources yourself, you're a dictatorship. Those of us who believe democracy is the most precious political value of all should be repelled to see it reduced to a propaganda term.

On an increasingly multipolar planet that has begun to disastrously heat up, the need for a shared set of rules we can all push our leaders to obey is greater than ever. But how do we make it work? We need to look beyond the cagey centrism of Obama – still too determined by America's oil addiction, and the capturing of its politics by big money – to genuinely radical ideas.

Albert Einstein thought the UN General Assembly should be directly elected, and in turn appoint the Security Council. This would create an even greater pro-UN momentum all over the world; and its peoples would immediately look to it in any crisis. The vision of a Parliament of Man is obviously distant, but it is a shimmering goal to begin progressing towards. John McCain would slap us back in the opposite direction – towards a Hobbesian chaos regulated only by raw American power.

j.hari@independent.co.uk

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