Anthony Cordesman has a long report out on Persian Gulf nation military power.
I can take or leave Cordesman as an analyst in regard to policy, but you can trust anything he puts out on events and equipment. He's thorough.
Just looking at the Iran-Iraq balance is disheartening. At least in the air and at sea, the cross-Persian Gulf balance lies with our side.
I don't think Iran could capture Basra, turn south, and roll through Kuwait and then reach Saudi Arabia's oil fields in the east (and then roll up the causeway to take Bahrain from the land side), but you never know what the Iranians might believe. They've been more prudent than that in the past, but as the clashes with the US Navy in 1987 and 1988 show, they can do stupid things.
This article is an interesting approach to fighting Iran if they try a form of psychological warfare by creating disorder in the Persian Gulf that they hope will inspire enough fear of oil insecurity to end the fighting. It assumes that Iran doesn't want to close the Strait of Hormuz, that the Iranians can't stop oil traffic with their attacks, and that we could best respond by staying out of the Persian gulf while we operate in the Arabian Sea and hammering Iran's assets with our longer-range weapons while keeping out of range of Iran's assets that can reach no farther than the Persian gulf.
The author has an excellent point. Defeating Iran doesn't mean we have to maintain a forward defense that gives no ground at all from H-Hour forward. If world oil supplies and reserves can be juggled to handle a short-term interruption of the oil flow, taking the time to destroy Iran's assets from a distance is the smart thing to do. At that point, we can then move into the Persian Gulf to close with and destroy the enemy that survives, and escort civilian traffic. I've already stated that carriers have no business in the Persian Gulf and it is an open question of what can be risked there in the opening stages of a war with Iran.
I have doubts that in the short run that tanker owners will decide losses will be at an acceptable rate and continue to carry oil through the Strait of Hormuz. And I have doubts that we can prevent Iran from inflicting damage on oil facilities on the Arab side of the Gulf in the opening hours or days of a fight. But it is valuable to understand that we can give ground in the opening days or weeks of a fight and it doesn't mean Iran is winning the war.
If we strike Iran's nuclear facilities, having an idea of what Iran might do in retaliation is a good idea. And knowing the playing pieces on the board is the starting point of that exercise. A lot of scary things that Iran might do are actually counter-productive. But you never know.
We should also remember that while we might view such a strike as a one-off and assume Iran will resume talking, Iran might believe we are at war and act accordingly. As far as I'm concerned, Iran has been waging war on us for over three decades--if our looted embassy and body count from Iraq directly linked to Iran is any guide. But it would be good to think of a strike on Iran's nuclear facilities as only one part of the opening act of a long war to destabilize and overthrow the mullah regime with the time our strike buys.
Remember, attacking Iran is a matter of national security and analysis needs to be deeper than tracking the effects on presidential popularity in October.