Leading article: A bank scandal that is also about trust

Abdul Qadir Fitrat, the governor of Kabul Bank, announced his resignation in Washington because, as he explained, he would have feared for his life if he had announced it in the Afghan capital. This was a useful corrective to the generally upbeat discourse that followed President Obama's announcement of a substantial pull-out of US troops.

A spokesman for President Karzai said Mr Fitrat had fled after the attorney general's office sent him a letter asking him to answer questions about the handling of the near-collapse of Kabul Bank last year. In September it was revealed that the bank had lost $850m in bad loans, 94 per cent of all the funds loaned out.

The Kabul Bank scandal involved powerful figures including Mr Karzai's brother Mahmoud, who borrowed huge sums to invest in property in Dubai, then failed to repay them. Mr Fitrat has fiercely rejected charges that he himself was implicated in the scandal: he called the report on the collapse written by a Karzai-appointed investigator "completely biased and completely unbalanced". There is no way of knowing where the truth lies. Quite possibly each side is as bad as the other. But Mr Fitrat's resignation, following the earlier scandal, casts a shadow on the West's plans to pull out.

Since the invasion of Afghanistan almost 10 years ago and the overthrow of the hated Taliban regime that followed, the US and its allies have poured great resources into the effort to transform Afghanistan from a medieval charnel house into a country with the rudiments of state institutions in place. At the heart of any state-building endeavour is trust: the belief of citizens that they can, at least to a degree, depend on the probity of the nation's political, judicial and economic infrastructure. Yet this, the most fundamental precondition of statehood, has yet to be fulfilled in Afghanistan.

The Taliban came to power with the support of millions of Afghans because they promised to be honest, and to bring justice to the country. It would be tragic if our failure to instil a culture of responsibility in Afghanistan's ruling class should send that unhappy country back to square one.