I can think of only one international body that can lay claim to a semblance of democracy: the United Nations. All the other organisations that regard themselves as global – the International Monetary Fund, the World Bank and the World Trade Organisation – are creations of the west and their power structures reflect that fact. This is the reason why the United States has always had a troubled relationship with the UN; it is the one organisation where it is not assured of getting its own way. On the contrary, it often finds itself hugely outnumbered, resolutions on the Middle East and Israel being a classic trigger. That, rather than being strapped for cash, is why the US has always been so reluctant to pay its dues. So, it was no surprise to find the US boycotting this year’s UN World Conference against Racism in Geneva, or that it walked out of the first such meeting in Durban in 2001. America is invariably on the defensive on such occasions.

Of course, western countries are bound to be on the back foot at any conference or gathering on racism. It is not that racism is an exclusively white phenomenon; every race is capable of and engages in racism. It is wishful thinking to believe that it is a solely Caucasian affliction: Rwanda, the civil war in Sri Lanka, Han Chinese attitudes towards Tibetans and Uighurs, or the prejudice shown by host populations virtually everywhere towards migrants, are just a few examples.

Racism, alas, is universal, but its impact has varied greatly, depending on the power of the particular people acting upon their prejudices. That is why white culpability has been far greater in the modern world than that of any other race. Slavery, colonialism and the less blatant forms of discrimination that have been associated with US hegemony – on display in American behaviour towards the people of Iraq and at Guantanamo Bay – have been inextricably intertwined with racism. Indeed, colonialism and slavery would have been inconceivable without racism, it being their rationale and justification.

Any UN conference on racism is therefore bound to be an extremely uncomfortable experience for western nations, especially the US. It is an occasion when the developed, former colonial world meets the developing, generally colonised world. The former much prefer to treat their colonial history with amnesia (which has become Britain’s default mode in relation to its past), but the UN gathering is an instance where that is not possible. The old imperial powers come face to face with the past, as the argument at Durban over reparations for those countries that suffered from colonialism and slavery well illustrates. The flashpoint at this conference – and, indeed, the previous one – has been Israel and its attitude towards the Palestinians. Given that Israel has been central to US foreign policy in a region that has been its greatest priority, it was entirely predictable that the Americans would seek to prevent criticism of either themselves or the Israelis.

In fact, the Israelis offer a sad example of the intractable and ubiquitous nature of racism. After the horrific suffering of the Jews during the Holocaust, the west sought to salve its conscience by taking land from the Palestinians, in an area that had been colonised by the European powers, and using it to help establish the Zionist state of Israel. The latter has, unfortunately, always borne many of the characteristics of a transplant, and was bitterly resented by those whose land was stolen. At the same time, Israel identified itself with the west, to which it looked for sustenance and protection, never seeking to establish a modus vivendi with its neighbours. This attitude was reciprocated.

And so, history has frozen in the Middle East, the paralysis taking the form of a state of war that has lasted longer than a half-century. The way many Arabs in Israel are treated as second-class citizens, and the brutality and cruelty shown during the Israeli assault on Gaza early this year, are eloquent testimony to the racism endemic in Israel. It is ironic that a people who suffered from racism on such an enormous scale should themselves display the same kind of attitude towards the Palestinians and their neighbours. It suggests that people do not necessarily learn from their history; and that those who have suffered so grievously may themselves even be particularly vulnerable to the same way of thinking as a result of their experiences.

There was little, if any, chance of these issues being explored in a useful way at the conference: they are too fraught. But that is not a reason to boycott or walk out. On the contrary, there is an absolute need for a serious global forum on racism. If it is difficult to talk about the phenomenon at home, it is far more difficult to do so at an international level. As a result, the incidence of racism – and its impact and effects – are hugely underestimated both domestically and internationally.

No people like to admit to their own racism; the response is invariably one of denial. This makes the UN conferences on racism – and there have only been two this decade – important and worthwhile events. They represent an acknowledgement that it is a global problem. They offer a forum where such issues can be aired, however sensitive they may be. They oblige the west to face up to its history and engage in a discussion with those whom it has discriminated against.

In this way, they might even assume some of the characteristics of a global truth and reconciliation commission. But that would require western countries to participate rather than boycott, and engage in a full-hearted manner, rather than walk out when words are being spoken that they would rather not hear.

Martin Jacques writes fortnightly in the New Statesman