Five years since the conflict in Darfur began, BBC News website's World Affairs correspondent Paul Reynolds asks why international concern has not been translated into effective intervention. 

The deep concern about Darfur felt internationally has not been matched by a similar determination to intervene. 

It is not from lack of knowledge. 

There have been many reports, from the UN and others, which have laid the blame largely at the door of the government of Sudan. 

The US has called the killings genocide, though the UN held back from using that word. 

All Talk And No Action In Darfur