British and American efforts to rebuild Iraq's police after the 2003 invasion were under-funded and unrealistic, the inquiry into the war has heard.
The first UK chief police adviser in Baghdad said there was an assumption that an efficient Iraqi police force would simply "rise like a phoenix" within months.
Douglas Brand, former deputy chief constable of South Yorkshire Police, criticised the lack of support he received, including the Foreign Office's failure to give him bodyguards for his first three weeks in Iraq.
He also highlighted a missed opportunity to model Iraqi intelligence on British lines because the UK would not send out an experienced Special Branch manager.
Paul Kernaghan, the Association of Chief Police Officers lead on international affairs from 2000 to 2008, said: "I do not believe there was ever a clear, comprehensive, realistic strategic plan for policing in Iraq."
Mr Brand arrived in Baghdad as the UK's chief police adviser to the Ministry of Interior in July 2003 having been briefed on a policing plan that he described as "high on aspiration but low on substance".
He told the inquiry it was "quite breathtaking" to compare the huge resources available for training the Iraqi army with the limited help for the police.
He said: "There was nothing for the police. There seemed to be this expectation that the police would just rise like a phoenix and just get on with things like they always do...
"In fact sometimes it felt quite lonely because there was nobody else recognising the fact that you don't have this quantity of trained police to do the policing job that everybody wants them to do. And in order to get more it's going to take an awful lot longer than the time frames that were then starting to be talked about."