You really think Iran hasn't thought of all these things? It has studied the Americans for decades, and coalesced its entire doctrine and strategy around such lessons learned.
I've read the report. It seems to focus on a conflict with Israel.
To have a real effect you would need thousands of missiles, 1.8 tons delivered, at the right point, yes it will cause a problem for an airbase, but it wont destroy the airbase.
For a thousand missiles, I guestimate 2/3 wont arrive at the target. So your hitting them with 300 x 1.8 tons.
Israel has 250 fighters, they could deliver that tonnage, accurately in one flight. then in the afternoon they deliver the same. This ignores what US forces did, Saudi, Dubai etc.
So I'm not saying you would lose all your missile bases, but all your power stations, barracks etc are gone. Once gone, they cant defend your underground bases, and then the enemy switches to 'seige mode' and just keep bombing your underground bases.
I dont believe anyone could stay in those bunker's, being hit every 10 minutes by a LGB or a cruise missile, slowly widening the lift shaft until they breach.
But I'm just an Armchair general. The real ones probably have other ideas.