IEDs are an immensely simple weapon that allows an unskilled, low-tech, pre-industrial force to extract casualties from a generally superior opponent. The value of the IED is not only does it allow what would otherwise be low grade cannon fodder to kill people with relative impunity, IEDs tend to kill several soldiers with a single blast. A lot, probably a majority, of IEDs are found by US forces before they are detonated and a the overwhelming majority of the remainder do nothing but created a pyrotechnic display.Source
.... U.S. soldiers on patrol here recently watched a man walk into the street with a bomb and begin to dig. They killed him before he finished. Out stepped another man to finish the job, so they shot him too — then another, and another and another.
In all, five people tried to place the makeshift bundle of munitions in the same hole within an hour.
"You see what we're up against," said Adam Jacobs, a 26-year-old Army captain, after recounting the astonishing story.
....The answer to getting the bombmakers has two fairly simple components, though as Clausewitz noted "in war even the simple is difficult." The first is to let the Iraqi Army, which is also suffering heavily from IEDs, read Miranda rights to anyone captured with explosives or an IED and then ask them where said materials are going to, or where they came from, while, of course, avoiding outrages against their person or dignity. The second is to kill the bombmakers or drive them out of the business by intimidation.
Of course, eventually the special forces advisors who are left behind to work with the Iraqi security forces may be given the green light by their hosts to do their worst to anyone in Iraq who designs and builds IED's. The kid glove treatment the US military has used toward the bombmakers cannot go on indefinitely. Too many US military personnel have been killed unnecessarily because lawyers in the US State Dept and the Pentagon have decided to shackle the hands of the men on the ground.
With the US gone, Iraqi leaders will have no such scruples.