First, let's just look at the feasibility of an attack from a U.S. Military standpoint, and discount possible consequences, even though those consequences are the really frightening aspect of possible war. This is known as the “Iranian regime will collapse on itself with a few well-placed bombs" strategy. It may remind you of the "We'll be greeted as liberators" strategy that has us on the smooth-sailing path to victory in Iraq. Despite neoconservative's utterly laughable assertions to the contrary, it should go without saying that our military options are heavily curtailed by our previous commitments. The War in Iraq is the largest, of course, stretching our military to the breaking point. Every few weeks you hear another General on the Sunday morning shows saying that we can't sustain the current level of deployment indefinitely. If current levels are prohibitive, imagine what a strain for the Army it would be if we invaded Iran as well!
Furthermore, Iran is roughly three times larger than Iraq, with twice the population. The ethnic group that would cause us trouble in Iran is not the minority it is in Iraq, but rather a substantial majority of the population. The Shiite population base for an insurgency is four times greater than is the Sunni population in Iraq, so if an insurgency does form in Iran (and I wouldn't hold my breath on that one), the threat posed by them would dwarf that from the Sunnis.
An aerial bombing campaign is the remedy the giddy hawks see for those otherwise insurmountable problems - just don't put in troops. Don't do any fighting where the bad guys can fight back. As a nice side benefit, dropping bombs on things does produce the best footage, and that would play nicely on the 24x7 news networks. Iran's upgraded defenses might actually cause hiccups for our sorties, though, since they haven't been strangled by years of sanctions as Iraq had. In fact, the Russians have been selling them defense systems like crazy. Given that, I wouldn't be blase about an air campaign, but it, at least, is an option while ground forces are not.
To begin, a little geography. The Persian Gulf empties into the Gulf of Oman through the Strait of Hormuz. The Strait is a two-mile wide shipping pathway bound by littoral waters though which 35% of world oil production is shipped, and which is bound on the north by Iran. The problem with that just screams. To wit: the Strait of Hormuz can be closed using 1980's or earlier technology, and there's absolutely no telling how high that would drive oil prices. Go to your local library and look at Jane's Weapons Systems - the anti-ship missile section alone is veritably bulging with the elegant lines of decades of perfected naval-killing ordinance. Even with modern CIWS (Close-In Weapons System) to attempt interception of incoming missiles, all your enemy need do is fire one missile more than the number of CIWS units they have on board simultaneously, and the target is literally sunk. One missile is enough, and with the predictable movements any large ship would be making in the constrained Strait, one missile would certainly get through. Here I'm being easy on the Pro-War argument by making no mention of Iran's recent acquisition of supercavitating torpedoes, new air defense systems, or Russian submarines. Hell, now that I mention the Russian subs, it occurs that all of those technologies are from the Russians. Gee, I can't wait for Russia to support our U.N. sanctions! There's no way they'd screw us on that, right?
As an aside: Why, then, do we still put so much emphasis on the Carrier Battle Group? Certainly, the ability to project air superiority anywhere in the globe is valuable, and they do have a strategy for avoiding having fleets sunk en masse. That strategy is called "We'll be more careful to keep ourselves away from possible missile sources." This is the "over the horizon" argument for continued relevance of the navy. However, it's just as true that, as Sinclair said, "It is hard to get a man to understand something when his salary depends upon his not understanding." Can you imagine the British abandoning battleships? You'd need retroviral genetic therapy to even get them to consider it! Plus, when your enemy can use ostensibly civilian boats to fire multiple missiles, the principles of asymmetric warfare start to apply, and in those cases we don't do well - "over the horizon" notwithstanding, since the attackers don't need to see you to shoot missiles at your shiny carriers.
The real issue is not the Iranians sinking our hardened targets - if you can call the giant target a battleship or carrier represents "hardened." The real issue is that oil tankers cannot be considered hardened targets, and cannot stay "over the horizon" as they navigate the Strait. As likely as it is to sink a navy warship with a single missile or mine impact, it is virtually assured when the target is a tanker brimming with fuel. Put a nice hole in one of those and 35% of world production has to be routed a different way. Even the credible threat of an attack on a tanker would probably close the Strait. Granted, there is some excess pipeline capacity in the area, but no alternatives for transporting that quantity of oil exist. There would be a bidding war for the remaining oil on the world market, and it would be fierce. America would take the hardest hit, since we're the biggest consumers. Even discounting lengthy supply disruptions, the economic consequences of $250/barrel oil are difficult to overstate. I have to imagine some starkly cataclysmic events before my Unlikely Alarm goes off. The fact that we are over a decade behind removing the threat to national security and civilization continuity posed by our total dependence on a limited resource is the central failing of our fathers.
In the list of consequences let us not forget that, as a majority Shiite nation, the Iraqi government naturally has strong ties to Iran. With the prominence of cleric Muqtada Al-Sadr, who is arguably becoming the most influential politician in Iraq, and the power wielded by the Ayatollah Sistani, two men with loyalty to Iran, a war with Iran could make things very uncomfortable for our troops in Iraq. Remember, our 140,000 servicemen and women in Iraq depend on poorly defended supply lines running North from Kuwait, right through the heart of the Shiite provinces. With the popular Shiite uprising either of these men could accomplish with a single fiery speech, our troops could be marooned.
Finally, there is Hezbollah, which is the most effective terrorist organization in the world, and which would be at the command of the Ayatollah Khomeini. Hezbollah has shown it's ability to strike in meaningful ways around the world, and it seems unlikely we could avoid a domestic retaliation.
And what real benefit would bombing the Iranians have? Unless the neoconservatives' magical bombing-away-the-regime strategy works, the prizes won by our "successful" air campaign would be transitory at best. By filling Iran's nuclear site's entrances with rubble, we could slow their program, but with the urge to retaliate they may redouble their efforts. In other words, it does nothing to solve the problem, and it escalates the current cold conflict to a state of open war. Iran will find a way to strike back, and they have a plethora of options to do us grievous damage.
So, I'm not saying that attacking Iran would be idiotic, I'm just saying that it is the stupidest idea that has ever existed, or will ever exist in the history of the universe. It makes going to war with Iraq look like thesis material.
Cross this with the fact that the Administration has seemingly done everything in its power to avoid serious and aggressive diplomatic engagement with Iran over our combined grievances - most importantly our explicit threat to their country and their nuclear program - and you see that they must not think Iran is actually that much of a crisis. Furthermore, the only derivable lesson from the immensely stupid Axis of Evil speech and America's subsequent starkly different treatment of Iraq and North Korea is that America will not mess with you if you have nuclear weapons. Who can blame them for acting on the only lesson available to them, as rational humans do?
Now, consider this critical post by the estimable Josh Marshall:
With respect to what's coming on Iran, what is in order is a little honesty, just as was the case with the Social Security debate a year ago. The only crisis with Iran is the crisis with the president's public approval ratings. Period. End of story. The Iranians are years, probably as long as a decade away, and possibly even longer from creating even a limited yield nuclear weapon. Ergo, the only reason to ramp up a confrontation now is to help the president's poll numbers.I agree completely with Marshall's sentiment. I pray my leadership is paying attention. My argument would change the penultimate sentences as follows: "There is no military engagement option against Iran, meaningful U.N. sanctions will be blocked by Russia and China, and the Bush Administration steadfastly refuses to engage aggressive diplomacy. Ergo, the only reason to ramp up a confrontation now is to help the president's poll numbers."
Of course, that's just the continuation of the thought. I prefer Marshall's from a message framing and structure standpoint.
Meta-Blogging Addendum: Blogging is interesting. There's so much more I feel the need to add, but I just don't have the time. I want to add shoot-down percentages, acknowledgements that the strategic situation isn't as cut and dry as my technology arguments make them out to be, CIWS variants, and nuance on the defenses the modern navy possesses to defend itself... It's great fun!