Lets analyze potential US-Iran war.
What US conventional military can do to Iran?
US NAVY:
If US Navy stays in the Persian Gulf, with high probability, their ships will experience the fate of Russian cruiser Moskva. In the event of war, US Navy will have to leave the Persian Gulf and operate from the coast of Oman beyond the range of Iranian anti-ship cruise missiles, anti-ship ballistic missiles and drones. Also the Straight of Hormuz will be closed with Iranian mines, missiles and drones.
If US Navy has to operate from the coast of Oman then F-18 can’t reach Tehran. Assuming US Navy concentrates 7-8 aircraft carrier battle groups, that is equal to 700 F-18 combat aircrafts and F-18 has a combat radius of only 800kms.
F-18 will have to fly 900kms from Arabian Sea to Qatari airspace, make aerial refueling there, and then enter Iranian airspace, and with combat radius of only 800kms they can only bomb southern and central Iran. Greater Tehran region which is home to 20% of Iran’s population and 50% of Iran’s industry will be beyond the range of F-18.
View attachment 970254
While making sorties to Iran, F-18s will have to make two aerial refuelings which will put strain on aerial refueling tankers, and also huge distances will reduce the total number of sorties by each F-18.
Iran claims to have 1500km range anti-ship ballistic missile. It is possible that Russian and Chinese satellites and Iranian patrol drones will try to locate US Navy in the Arabian Sea and if US vessels are located, they can be targeted by Iranian 1500km range anti-ship ballistic missiles.
US AIR FORCE:
It will take couple of weeks for US Air Force to deploy to airfields of Saudi Arabia, which has 25-30 airbases and civilian airports. However most of their airfields are located only 300km away from Iran, Iraq, Yemen and are vulnerable to strikes by cheap kamikaze drones and short-range ballistic missiles. These bases must be evacuated and combat aircrafts must be deployed to far away located bases beyond the range of Iran’s large arsenal of short-range ballistic missiles and drones.
View attachment 970262
There are roughly 13-15 airbases and airports in central and western Saudi Arabia which are located 700km-1200km away from Iran and its clients. These airfields will have to house roughly 1500 combat aircrafts, which means 100 combat aircrafts per base.
There are no hardened shelters in Saudi airbases and US aircrafts will be parked like this:
View attachment 970264
These aircrafts will be vulnerable to strikes by ballistic missiles with cluster warheads, cheap kamikaze drones and cruise missiles.
Against 1500 combat aircrafts, Iran can use 1500 medium and long range ballistic missiles, 600-800 cruise missiles and thousands of Shahed-136/Arash-2 kamikaze drones. Even if Iranian strikes will be 30% effective, US will lose hundreds of aircrafts and will not be able to conduct effective air campaign.
Russia and China will provide real-time targeting data to Iran from their satellites.
Most of aircrafts of US Air Force are F-16s that have a combat radius of only 540km. F-16s will have to make multiple aerial refuelings for reaching Western and Southern Iran, while Greater Tehran region and Mashhad will be beyond the range of F-16s.
Iran can use its kamikaze drones/cruise missiles/ballistic missiles to target fuel depots, aerial refueling tankers, transport aircrafts, ammunition storage facilities and runways for the purpose of paralyzing US Air Force (with Russia and China providing precise targeting data from their satellites).
Also both US Navy and US Air Force have to establish air superiority by suppressing Iranian air defense systems. 3rd Khordad is 15 years, 15th Khordad is 10 years and Bavar 373 is 8 years in mass production, so there might be multilayered air defense network in Iran.
US GROUND FORCE AND MARINE CORP:
It can take 3 weeks for Iran to concentrate 200.000 troops and 1500 tanks in Khuzestan province and attack 1-2 armored brigades US has in Kuwait. Iran can invade Kuwait and create threat to Saudi oil fields, while Shias in Bahrain and Eastern Province of Saudi Arabia will rebel against local governments.
In the previous Gulf Wars it took 6 month for US ground force to arrive to the region. However, this time Iran will close the Straight of Hormuz, while Houthis will close the Bab-el-Mandeb Straight with drones, cruise and ballistic missiles.
Since Straight of Hormuz will be closed, while passing through the Straight of Bab-el Mandeb will be dangerous, US will have to deploy its ground force in Western Saudi Arabia via the Red Sea ports and move from there towards Eastern part of the Arabian Peninsula for the purpose of protecting Saudi oil fields.
There are several ports in the Red Sea and Israel that can be used for deployment of US ground force: Port of Eilat in Israel, Port of Yanbu and port of Jeddah in Saudi Arabia.
View attachment 970265
However, Port of Jeddah is only 60km away from Mecca, while Port of Yanbu is 140km away from Medina. Mass deployment of infidel forces who fight on the side of Jews against 5 Muslim states (Lebabon, Syria, Iraq, Yemen, Iran) near Masjid Al Haram and Masjid an-Nabawi will cause upheaval throughout the Islamic world and completely discredit the Saudi royal family. And it is not clear whether Port of Eilat alone has a capacity to handle mass deployment of US ground force.
But even if they deploy in Western part of the Arabian Peninsula, distance to Ghawar oil field is 1200km and supplying hundreds of thousands of US soldiers at that distances will be a huge logistical challenge even for US.
US Marine Corp can arrive faster than US Ground Force, but they have light equipment.
And then US has 5000 Tomohawk cruise missiles. But most of these missiles are old and unreliable as 2017 Shayrat airbase strike showed. During that strike on Syrian airbase most Tomohawk missiles failed to hit their targets. Assuming US Tomohawk strikes will be 30% effective, US can hit 800 targets in Iran with 1600 Tomohawks (2 Tomohawk missiles are usually launched per each target).
Finally, we have to answer the question - what are the goals of US war with Iran? There can be 2 goals:
1) Fight Iran for the purpose of helping Israel in its war against the Axis of Resistance
2) Punish Iran by weakening it with massive bombing campaign.
But 1) helping Israel by sacrificing Saudi Arabia, Kuwait and entire Persian Gulf oil infrastructure is not a good idea and 2) punishing Iran by bombing campaign is not a good idea either, because Iran’s response in the Straight of Hormuz and against oil infrastructure of the region will devastate global economy in general and US economy in particular.
Conclusion is that US has no good options for fighting Iran and its Axis of Resistance.
1) US Ground Force can arrive only after 7-9 months and they can’t enter the Persian Gulf and if they operate from the ports of the Red Sea, their overland supply line will be 1200km long.
2) US Navy will have to operate from the Arabian Sea and this will reduce F-18 sortie rates, while putting strain on aerial refueling tankers.
3) US Air Force will have limited number of airfields for mass deployment and those airfields will be under massive ballistic missile/cruise missile/drone strikes of Iran with Russia and China using their satellites to provide precise targeting data to Iran.
4) There is multilayered air defense network in Iran with multiple indigenous air defense systems and most US combat aircrafts don't have the range to reach more developed regions of Iran like Greater Tehran region (20% of the population and 50% of Iran’s industry), Tabriz or Mashhad.
5) There are no clear goals of this war, while Iran’s response in the Straight of Hormuz and Bab-el-Mandeb will devastate global economy.