Not sure that you are correct.
It appears to me that it has been al-Qaeda and Sunni based insurgents who have been IED'ing our troops.Up until recently, the Shiite militias have been targeting Iraqi civilians.
I suspect, our delay in dealing with the Shiite militias is because we want the Iraqi security forces to remove the Shiite militias instead of our precious soldiers putting their lives on the line going door-to-door doing the dirty work.
That scenario probably saves American lives.
I disagree.
Killing terrorists saves lives.
Letting Sadr and thousands of his soldiers walk around free does not, IMHO.
The politicians should stay the hell out of battle planning, and let the soldiers do their jobs.