Though the Iraqi and police were given vehicles ranging from Humvees to forklifts, they lack the resources to fix them should they suffer mechanical failure whether it be from normal use or an IED. So even as the number of trained Iraq forces grows, the number of vehicles they can use to secure Iraq has decreased.
However, the most crippling shortfall has to do with the supply of fuel. Currently, Iraqis rely entirely too much on US fuel supplies, so if for some reason US fuel is unable to reach an Iraqi base, that base will be crippled. Without gas for their vehicles, security forces simply cannot conduct the operations which the US will now be relying on more and more. The WSJ writes:
Concerned that an Iraqi military base had grown too dependent on U.S. supplies, American officials decided to test how it would cope if forced to rely on its own supply lines for fuel. The result: three days of intermittent blackouts.If the US does not begin addressing these issues immediately, it may find Iraqi security forces to be more of a burden than a benefit in its efforts to secure Iraq.
U.S. troops finally rushed emergency fuel to turn the base's lights on and keep its vehicles moving. "The Iraqis were not stepping up," says Lt. Col. Kenneth Kirkpatrick, who supervises logistics at the Taji base on the outskirts of the Iraqi capital.