Some 190,000 assault rifles and pistols supplied by the US to Iraqi security forces in 2004 and 2005 have gone missing, according to a report issued here yesterday, and may have fallen into the possession of insurgents.
The embarrassing disclosure, by the watchdog Government Accountability office (GAO), means that the Pentagon does not know what happened to roughly a third of the arms it has provided to train and equip Iraqi forces - an effort whose success is crucial to restoring some semblance of order in the country.
The "lost" arms include 80,000 pistols as well as an estimated 110,000 of the Soviet-made AK-47 assault rifles, many of them originating in eastern Europe, especially the former Yugoslavia. A recent Amnesty International report claims that, in 2004 and 2005, more than 350,000 AK-47s and similar weapons were removed from Bosnia and Serbia by private contractors working for the Pentagon and sent to Iraq, with the approval of local Nato and European commanders.
In addition, some 135,000 pieces of body armour and 115,000 helmets have also vanished, again perhaps to end up in the hands of insurgents. So far, the US has spent more than $19bn (£9.3bn) on developing Iraqi security forces, including almost $3bn on weapons.
According to the GAO, the distribution of the weaponry was "haphazard and rushed," and failed to follow established procedures - accusations the Pentagon does not dispute.
But the affair could be even more problematic for the White House, given that, during the two years under scrutiny, the programme was headed by General David Petraeus, now the top US commander in Iraq, in charge of the current troop "surge". President George Bush now lauds his talents on an almost daily basis, as the man who will finally give the US the upper hand against the insurgents.
The GAO arrived at its figures by comparing the property records of the Multi-National Security Transition Command for Iraq against records kept by General Petraeus of the arms and equipment he ordered. The Pentagon says it is now reviewing procedures "to ensure US-funded equipment reaches the intended Iraqi security forces."
But the controversy fits into a now familiar pattern of mistakes made by the US in Iraq, dating back to the initial failure to secure arms caches found in Iraq immediately after the 2003 invasion, and which merely fuel the insurgency the Americans are trying to stamp out. In this case, says the GAO, the military was "consistently unable" to collect supporting documents showing the weapons had been sent to and received by the intended parties.
There were also "numerous mistakes due to incorrect manual entries". But the military argues that the situation on the ground was so urgent, and the agency responsible for recording the transfers of arms so short staffed, that field commanders had little choice in the matter. "We could have held on to them until every bit of a logistical and property accountability system was in place," one unidentified officer told The Washington Post, which first reported on the missing arms yesterday. Or, he continued, "we could issue them in bulk on some occasions, to the US elements supporting Iraqi units who were needed in the battles." In Fallujah, the scene of fierce fighting in late 2004, one recently created Iraqi brigade dissolved and later used its weapons against American forces.
The GAO findings will be grist for the mill of opponents of the war, less than six weeks before the scheduled report to Congress by General Petraeus and Ryan Crocker, Washington's envoy in Baghdad, on whether the "surge" is succeeding.
That report may be a watershed moment for Iraq policy here. With public patience with the war all but exhausted, and elections barely a year away, many Republicans loyal to Mr Bush have hinted that, barring cast-iron evidence the "surge" is working, they will no longer support the war.