In the wake of the leaked video of the "friendly fire" death of UK soldier Matty Hull, BBC defence correspondent Paul Wood examines the apparent disparity between reports on the incident.
The US pilots who accidentally shot and killed Matty Hull in Iraq were cleared by a Pentagon investigation - and criticised by a British inquiry. But even a US general questioned whether the two pilots should face charges.
"I feel sick."
Did avoidable mistakes lead to Matty Hull's death?
This was the stricken reaction of the American pilots as they realised they had fired on friendly forces.
Not the casual reaction of "cowboys out on a jolly", as they were described by one injured British soldier at the time.
Nevertheless, did avoidable mistakes lead to the death Lance Corporal of Horse Matty Hull?
On the face it, the British and American inquiries reached very different conclusions.
"In the uncertainty of a wartime environment, accidents can and do happen," said Major General Larry Lafrenz, commander of the Idaho National Guard, the two pilots' unit.
Indeed, the Pentagon investigation, begun right after the incident in March 2003, cleared the two pilots of any wrongdoing.
It said that they had "followed the procedures and processes for engaging targets".
It added: "Neither the pilots nor the forward air controllers acted with negligence, clear violation of procedures, or reckless disregard for the foreseeable consequences of their actions."
By contrast, the British military board of inquiry found the rules of engagement had not been followed.
"During the incident, there are examples of non-standard procedures and... lack of situational awareness," it said.
The American pilots were experienced flyers, both with thousands of hours logged in the cockpit. But they had had no combat experience.
And they had received no training in how to recognise British armoured vehicles, even though the UK represented one quarter of the ground force for the Iraq invasion.
Both the US and the UK inquiries agree on this background to the incident.
In fact, a close reading of both reports shows they agree on the sequence of events which led to the American pilots firing on the British convoy.
The pilots did not have a clear idea of where they were and where the enemy was.
So when their forward air controller radioed in that the area was "clear of friendlies", he was talking about another location altogether, an area north of a canal outside Basra, where Iraqi forces had been spotted.
The A-10 tankbusters were flying south of the canal, where only a small force of the Household Cavalry was located, pushing north during what they thought was a welcome pause in the day's fighting.
That confusion over what the military calls "situational awareness" need not have been fatal as the British armoured vehicles were identified with orange panels, showing friendly forces.
But then, tragically, the pilots mistook those orange panels for "orange rocket launchers" - and went in for the kill.
The US inquiry was convened by General John Abizaid, who went on to become the American commander for the Middle East.
In a forward to the report he asks for the commander of coalition air forces to reconsider whether the two pilots should face any charges, given the long list of what went wrong.
General Abizaid writes: "The findings that cognitive and physical task overload, ineffective communication and failure to recognise identification panels that contributed to the terrible loss of life are difficult to square with a finding that no procedures were violated".
The A-10 pilots mistook the orange panels for rocket launchers
Astonishingly - but not surprisingly, given the detail in both reports - he recommends: "The commander, Coalition Forces Air Component Command should reconsider the actions of subordinate personnel for possible administrative or disciplinary action as he may deem appropriate."
But the four star general's view has so far been ignored.
It is, perhaps, all too easy to second-guess the actions of two pilots under the immense pressure of combat conditions.
In the battle for Basra, the enemy often hid among the civilian population, using so called shoot and scoot tactics.
Target identification was always going to be a problem.
Friendly fire is an accident of war which is stubbornly difficult to eliminate.
One historian estimated that up to 20% of American casualties on D-Day were examples of what the military calls "fratricide".
In the case of this particular incident, both the US and UK boards of inquiry recommended that, in future, pilots should radio in their target co-ordinates, and then fire only if they get clearance.
Had all these steps been taken in the case of LCoH Matty Hull, it is possible he might still be alive today.