Yes, I'm sure we are using some troops from the 101st to help guard those supply lines. That is a very important mission as the 3rd ID prepares to engage the Republican Guard. However, they aren't staying stationary " watching trucks roll by". They are patrolling the supply routes in their Blackhawks, ready to quickly respond to any attacks. I'm sure as more troops from the 4th ID and other units the make it to Iraq the 101st will be relieved of this responsibility.
As for the airfield in B-city, that sounds like a mission for the Rangers. We haven't heard much about the Rangers, but I think all three Ranger Bat's are out West someplace and we should be hearing from them when the time comes to take Baghdad.
"Iraq set for more sandstorms"
Don't suppose the Marines would use the cover of these sand storms to move into position do you?