In western Africa, there is a strange, jagged shard of pre-Civil War America, forgotten by the ages. Its language is American-English, spoken with a Deep South accent. Its currency is the dollar. Its rulers have had American names like Joseph Roberts, William Tubman, and Charles Taylor. Its capital is named after the USA's fifth President, James Monroe. Its flag has alternating red-and-white stripes with a dark blue square in the upper-right corner which contains a star. Its name means "land of freedom". And right now, they are begging for America - the land they model themselves on - to save them from Hell.
Liberia is something of an embarrassment to the Americans now. It was founded in the early 19th century for liberated slaves who wanted to be "repatriated" to Africa. The founders of the new country - declared independent in 1847 - modelled themselves explicitly on America's founding fathers, with a constitution, a democracy - and a caste of enslaved inferiors. The ex-slaves took the natives of Liberia as their chattel.
So - a century-and-a-half later - what has become of this strange, tiny country that America made? A few weeks ago, there was a typical Liberian scene: the US embassy in Monrovia was under siege from thousands of desperate Liberians begging for US intervention in their country. "Take action now in Liberia, as they have in Iraq!", one man cried to American personnel. "Send the Marines to guard us!", called another. Many wealthy, comfortable Westerners imagine that the wretched of the earth want less America, and in some cases, like Colombia, this is true. In Liberia - as in Saddam's Iraq - the opposite is the case. The UN Secretary-General, Kofi Annan, backs the Liberian people: he has urged the US to act.
The Liberians want and need American intervention to rescue them from the civil war that has engulfed their country since the Americans disengaged in the early 1990s at the end of the Cold War. Charles Taylor, Liberia's thuggish President, has been indicted for war crimes and has mooted stepping down over the last few weeks - but still his forces ravage the country. Many people look at the horrors of Liberia and simply lose hope. Last month, I was speaking to a very well-known conservative historian who said, "Your evangelism for liberal democracy - if it isn't already discredited in Iraq - collapses when applied to Africa. Look at Liberia: a Western democratic implant, surely the best of all prospects for democracy there. And just look at it: it's a basket-case. All we [in the West] can do is leave the Africans to it for a few centuries and peek our nose in once every 50 years to see how they're getting on." This is the honest conservative position: stop your liberal utopianism and leave them to their slaughter.
The obvious retort is: many of the problems of Liberia have been caused by Western actions. Its economy cannot develop because Western agricultural subsidies strangle African farms in their cot. And there have been sordid geopolitical manoeuvrings too. The US, for example, backed Samuel Doe as Liberia's leader after he staged a coup in 1980 and constructed a horrifying apparatus of repression.
But more importantly, the question of Liberia needs to be seen in the context of there being three very broad-brush ways forward for the relationship between the rich world and Africa. The first is colonial exploitation. America's behaviour towards Liberia during the Cold War is a good example. Because Liberia's territory was a handy base in the fight against Communism, the Americans happily allowed their people to be abysmally mistreated. There are forms of colonial-style exploitation that still persist: international debt - whereby the rich demands annual payouts from the poor - is only one example.
The second option is the polar opposite: total disengagement. It is not hard to see why this is appealing: the brave and often inspirational African liberation movements from the 1950s to 70s called simply for Africans to be given their own space to develop freely. But the result of this approach, where it has been tried, has, alas, also been a disaster. Liberia, abandoned by America since the end of the Cold War, has sunk ever deeper in blood and psychosis.
There is, however, another way. It is described by Michael Ignatieff, the theorist of the Kosovo war and of humanitarian intervention, as "imperialism lite". This model requires rich countries (and not just the West: in comparative terms, South Africa, for example, is rich) to intervene in failed states, so long as the people in that state clearly want us, in order to ensure stability and a transition towards a more liberal democratic system.
The best possible example of this "imperialism lite" was carried out by our own government in Sierra Leone just three years ago. Tony Blair sent in British troops to protect Ahmed Tejan Kabbah's government - judged by international observers to have been elected in free and fair elections - from the Revolutionary United Front, who were horrifically brutal thugs with a predilection for chopping off the hands of people they took a dislike to. The success of that country is now a standing retort to cynics like my historian friend. Even Noam Chomsky, the chief critic of American and British foreign policy, told me at a New Statesman lunch that he thought Sierra Leone was "perhaps" the one genuine example of a humanitarian intervention - but, he added, "that's probably because I haven't looked into it properly."
Much as we might have a gut reaction against imperialism, "lite" or heavy, if we had not acted, Sierra Leone would be a bloody mess. Thousands of innocent people would have seen their children murdered or their mothers raped. Overcoming our distaste for imperialism - which is based on acts carried out in the Raj and elsewhere under a totally different and more shameful model of imperialism - is a small price to pay to save those people. Liberia is only next door to Sierra Leone: George Bush should look to his friend Tony's example to find out how to respond to the people howling at his embassy's door.
But crises such as Liberia's will keep cropping up again and again. In the long term, we cannot rely on the (at best selective) goodwill of the Americans to deal with these problems. Arguments for a world peace-keeping force have long been floating around, but this weekend, even the famously unilateralist Donald Rumsfeld said this would be "a good idea". An international force trained to keep peace in civilian areas - rather than only to bomb, trash and conquer - would, Rumsfeld may have realised a little late in the day, be making a far better job of Afghanistan and Iraq right now.
Blair - with the example of Sierra Leone behind him - is in a perfect position to make the case for a standing army. Peter Stothard's new book describing Blair's behaviour during the recent war reveals that the Prime Minister tries to be as consistent an interventionist as possible within political reality. "What amazes me is how happy people are for Saddam to stay," Blair said. "They ask why we don't get rid of Mugabe, why not the Burmese lot. Yes, let's get rid of them all. I don't because I can't, but when you can, you should."
Take a pious position opposing this if you like; I expect a raft of e-mails about the evils of imperialism in any form. But can I suggest that you direct them not to me but to the people of Sierra Leone and Liberia?