Except you're forgetting the "no-fly" zone. We have prevented Saddam from exercising sovereign authority in that area for 12 years.
Does this mean Saddam couldn't send his army there ?
All of human history, up until sometime last century, has shown that you don't need to fly to be able to exercise sovereign authority.
Enforcement in the no-fly zone has only been against Iraqi aircraft and anti-aircraft facilities. Otherwise we could have just lined up our troops at the no-fly boundaries before the invasion.