Caught in the Vise
No one has suggested why the US has go to after the Sadr forces now. Moreover, we all know that the so-called Iraqi Army is largely Shi'a and going after other Shi'a while the Sunni insurgents are bombing their relatives was only going to produce this [Via the NYT]:
Iraqi Unit Flees Post, Despite American’s Plea
"This episode was a blow to the American effort to push the Iraqis into the lead in the struggle to wrest control of parts of Sadr City from the Mahdi Army militia and what Americans and Iraqis say are Iranian-backed groups"