The latest consequence of the prison abuse scandal in Iraq is an unexpected setback for the United States. But the Bush administration is in no position to complain. For the past two years, US troops on United Nations peacekeeping missions have enjoyed a privileged status - immunity from international war crimes prosecutions. In order to secure an extension of this immunity, the US needed a new UN Security Council resolution. But it could not count on getting the nine votes required and so conceded defeat. This was a rare example of the council standing up to its most powerful member. The biggest factor behind the opposition was undoubtedly the controversy over the ill-treatment of Iraqi prisoners by US soldiers. Members understandably found it difficult to justify supporting the US at such a time. It would have meant granting immunity to American troops for precisely the sort of crimes they have committed in Iraq. Such a position would be hypocritical and morally untenable. China played a key role in frustrating the US bid. In 2002, it backed the exemption - but not this time, saying the US could no longer expect a blank cheque. The outcome will boost the credibility of the security council and avoid a damaging split so soon after unanimity was finally reached on the future governance of Iraq. This was clearly a factor that prompted the US to abandon its plans. But the decision is also a boost for the whole system of international justice and the rule of law - which the US has, through its actions, been seeking to undermine. The International Criminal Court opened for business in 2002. It plays a role first envisaged in the aftermath of the second world war - providing a permanent forum for trying people responsible for the most serious of crimes. The court will step in when nations are unable or unwilling to prosecute themselves. And it will apply only to offences committed in a country that has consented to the court's jurisdiction - or offences perpetrated by that nation's citizens. It would not have applied to the prisoner abuse in Iraq. But the US is concerned that other operations involving its troops may put them at risk of prosecution. Surely, this should be welcomed. It would act as an added deterrent. The US has become one of the strongest opponents of the court. It is no longer a signatory to the relevant treaty and has successfully pressed other countries into agreeing not to refer accusations against American citizens to the court. The time has come for the US to stop attempting to frustrate laudable international efforts to ensure that crimes of the worst kind do not go unpunished. The prison abuse scandal in Iraq might explain why the US fears the court. But it also demonstrates why this new judicial institution is needed.