In 1991, Baghdad was the most heavily defended city in the world, with overlapping SAM coverage, redundant command and control, and backed by the 7th largest airforce. They had state of the art Russian tech. The US took that system apart on the first night.
I really hate this: "wait till the US face a 'real' opponent arguments". The US military is combat veteran. It has fought more wars in the past 20 years than Iran, China, and Russia put together. It has proved itself capable of commanding large air armadas and supplying multi-Corps army formations on the move. No amount of training can recreate the "fog of war". Lastly, when was the last time Iran or any other country had an air exercise that involved thousands of sorties in ONE day. The last time the US did that was this month in Red Flag, the last time the US did that in actual combat was in 2003.
Prowlers are being replaced with Growlers
The US had covertly procured Soviet weapon systems for years from third parties. This information was just recently declassified. USAF aggressor squadrons flew Migs in the Cold War.
The Iran will spend $700 million dollars on a compromised system because there is no other alternative. It is the best system for the money. It's not like they can go to another vendor.
That explained why there's war everywhere for the past 20 years. Probably the judgment for it was to get enough war experience. ff