The discussion about MARV maneuverability for anti-ABM purposes might create a wrong impression:
Irans (conventional) missile force has such a high access denial potential, that this has been the reason why neither Americans, Israelis, Saudis or any other neighbor has attacked Iran yet.
Basically the Shahab-3 was enough to create such a access denial scenario. It is cheap and its CEP might be up to a kilometer.
But if it is equipped with a submunition warhead, it not only increases its destructive power, it also becomes immune against almost all ABM systems. The scenario is a 1998 vintage Shahab-3 upgraded with a warhead section that contains 10 sub munitions with cost effective ablative thermal shielding and release just after mid-point apogee reached.
Neither THAAD nor Arrow-2/3 nor PAC-2/3 could effectively intercept that payload.
Such a submuntion Shahab-3 is very cost effective and it's useful against large targets like airbases, even if they are hardened.
Another scenario: each of the 20 major enemy airbases around Iran in a belt between 1000km to 1500km need to be shut down to deny effective employment of airpower by the enemy. For 24 hours a day randomly at about 1 missile every 30 minutes each of the bases are attacked. So every day of such a intense scenario 1000 Shahab-3 are spent on access denial purposes of enemy airpower. If this is done for one week, 7000 Shahab-3 are spent and each of the 20 bases and 3500 100kg submuntions have impacted the 3x3km target, every square kilometer of this hardened target has been attacked by around 350, 100kg high velocity warheads.
The airbases will receive early warning about incoming missiles if the radar systems are still working and otherwise satellite sensors can provide coarse data on what might be the target. But operating aircraft in such a continuous attack condition that will involve operation limiting damage and necessary repair work, will have very bad impact on morale. The whole idea of airpower is at risk and this also means that the engaging ground based missile force can't be engaged in return effectively. Bases beyond the 1500km belt become much less relevant for the enemy airpower, because the ranges are outside what tactical aircraft are capable to operate from. This means special assets like F-22 or land based F-35 can't be effectively used.
The number to get that job done, the 7000 basic Shahab-3 might sound too high but how much would one cost and how much budget is needed over lets say 15 years for that? Is this capability worth such a investment?
The situation gets better as the airbases come closer. At Qiam and Shahab-2/1 range the engagement of airbases which project enemy airpower will become cheaper or much more intense. At twice the intensity --> 4 missiles every hour operation might become completely impossible and all short-legged aircraft thus fall out of the war equation.
This is real situation beyond MARV equipped missiles and this is why I disagree with baradar Yavar: IRGC-ASF conventional missile force, is very well useful in a non-nuclear conflict.
It can also be confidently said that Israel was never in a position to attack Iran. Israeli bases, around 10, are very well hardened but after the initial attack the IRGC missile force could badly maul their airpower within a few day long operation --> Israelis would need to use nuclear warheads and this was no option for such a limited operation.
Now Israelis have the nuclear card beside airpower but Saudis with their 10 super bases and 110mrd $ more F-15 would still face the same fate of the described scenario. Iranian missile bases are too well hardened to destroy their fighting capability with a preemptive strike by 1000 Saudi F-15 (plus the still fresh airdefences which will let the missile force start the access denial chain).
However once Iran would become an official nuclear power, this concept of conventional anti-access ballistic missile would become obsolete: A single Shahab-3 launch would trigger a nuclear response by Israelis and Americans.
PS: After reading this you might realize why it was the best idea in modern Iranian military history to dismiss airpower and renovation of the IRIAF and invest everything on the ballistic missile force.
