They could easily be out in about ten weeks.

They would destroy a lot of military equipment, precisely so it wouldn't fall into the hands of the insurgents, just as we did in Vietnam.

We would abandon the infrastructure, because it can't be moved anyway, so you would never bring it back with you anyway.

Much could be removed in six weeks time, considering much of the equipment doesn't "belong" to the US, it "belongs" to the contractors.

The contractors would be on their own to get out.

The End.