101st could be a second wave unit/reserve. If deployed they might stage out of Oman or UAE(Dubai). They could be airlifted into airports on the Iranian coast after the Marines and 82nd have secured such. Or they could stage in via the decks of LHD/LHA after their Marine contingents have put ashore.101st is air assault. They use helicopters which have to have somewhere to take off from.
Right now, their general staff is in charge of supporting the border ops in Arizona. I live just outside Fort Campbell.
10th Mountain would also be a likely suitable unit for deploy. Along with Rangers and SOFs.
Much may depend upon how the populace acts in removing the theocracy, how the locals in Western Iran lean, etc.
Might consider ally with Kurds and/or Bolochs to establish their own autonomous "homelands", as further "headaches" for the Mullahs.
There are options and ways to get it done, if such is the plan and resolve.

