E.G., NAZI war production reached a peak in late 1944! "Surgical strikes" etc. are PR terms, not military words. Today's smart bombs are truly amazing, but we (and others) have been bombing ISIS for over 6 months and they are still fighting, hopefully just not as efficiently.
Iran is nowhere as well developed or organized as NAZI Germany was, but it has a similar population, well developed armed forces, and in general is quite a few cuts above Third World status. In other words, we are not going to knock them out overnight. Think "dieing rattlesnake."
As far as "underground facilities" go, I would not assume we know where ALL of them are. The Iranians were masters of dirty tricks and nasty surprises in 500 BC. Also try and remember these Worthy Oriental Gentlemen were our staunch allies until Jimmy fell in love with fellow anti-semite, the Ayatollah Khomeini, whom he conflated with an O.T. prophet.
BTW, thanks for a very informative link. I hope the superannuated dingbat millionaires who represent us in Congress and their Left Wing staffs are as well informed.