While the CIA or Special Forces may not have had people in southern Iraq, allies of ours probably do. So someone in our government probably knows something about the situation in southern Iraq. Here is where that half of the Iraqi population that are Shia live. The Iraqi Shia do not like Saddam, for Saddam represents the Iraqi Sunnis (20 percent of the population) who have been oppressing the local Shia and Kurds for centuries. During the centuries when the Turks ruled the area, the Sunnis would join the Turkish army and keep the Shia (suspected of being pro-Persian) in line (the Turks took care of the Kurds, for back then northern Iraq was part of Turkey proper). If you are going use "Afghan Tactics" in Iraq you have to motivate the Iraqi Shias (and some of the Iraqi Sunnis) to rise up against Saddam. The Shias tried that in 1991, and Saddam has been hammering them ever since. Lots of Iraqi secret police in the south, lots of paid (or terrorized) informers. Much of the marshlands of been drained so the Shia "Marsh Arabs" have no place to hide if they decide to rebel again.
The probable reason why the Pentagon is against using "Afghan tactics" in Iraq is that our local allies, the Shia Arabs, are not ready for prime time. The White House civilians, who have watched too many movies and not enough real battlefields, are probably insisting that the Shias will feel more aggressive once the Special Forces and the smart bombs show up. Maybe so, but the Pentagon crowd is not willing to be their soldiers lives to settle what amounts to a bar bet. Especially when the generals know it's probably a bad bet. It's easy to be a betting man when you have little to lose.
The debate continues, among American military and political officials, about how to deal with Iraq. Political officials are urging the use of "Afghan Tactics" (small numbers of Special Forces backed by lots of warplanes). The big problem with trying the "Afghan tactics" in Iraq is that there are some significant differences between the two countries. First of all, there are no warlords (except for the two Kurdish factions in the north, who seem to prefer fighting each other.) There is no Northern Alliance. Most of the Iraqi population is not armed, and their only experience with guns is what they got when they were drafted for their military service (in other words, not a lot.)