The IAF is equipped for such an ability against much closer neighbors. Iran is about a thousand miles away. And given the massive deep-earth tunneling system the Iranians have developed, probably with North Korean assistance - it is highly doubtful that air power alone could neutralize or significantly degrade most perceived threats. In the case of Iran it is not simply a matter of knocking out a reactor or hitting a few key sites. Their system is considerably more complex than that with much harder to locate targets with many deeply buried underground.
Furthermore if Israel is directly involved in initiating such attacks, Israeli initiation would make it politically improbable if not impossible, for the United States to get the Gulf States on board if the U.S. were to get involved - This would be an absolute necessity if U.S. were to carry out the kind of massive sustained campaign required to neutralize the perceived Iranian threat and to significantly degrade their nuclear program.
As much as most Gulf Arabs fear and loathe the Iranians, they have no desire to put themselves in the direct line of fire from Iranian retaliation - which they do indeed have the ability to carry out in a very big way. Although Iranian weaponry is antiquated by Western standards..they have lots and lots and lots of short and medium range missiles - which are deeply embedded in hostile terrain - and very difficult to neutralize - that are more than capable of wrecking a great deal of havoc and carnage on the oil infrastructure in the Gulf States - which are just across a relatively modest body of water from Iran.
to quote from the NYT article above:
Unlike in 1981, when Israel destroyed Iraq’s nuclear reactor at Osirak, there is no single target. A sustained bombing campaign would end up killing many civilians and still might not cripple Iran’s nuclear program. Tehran also has many frightening ways to retaliate. And even Arab states who fear Iran shudder at the thought of America, or its ally Israel, bombing another Muslim country and the backlash that that could provoke. http://www.nytimes.com/2008/06/10/opinion/10tue1.html?_r=1&oref=sloginEscalating oil price on the world market does create a certain degree of deterrence against such an attack. It is probable that oil prices would almost certainly shoot up to $300 a barrel within one week. It is also quite possible, in fact one could say probable, that oil extraction, refinement and transport out of the Gulf would be greatly crippled for a long, long time thus creating a REAL and a likely long term economic crisis for the whole world that would almost certainly last for several years perhaps even decades
"I think of war with Iran as the ending of America's present role in the world. Iraq may have been a preview of that, but it's still redeemable if we get out fast. In a war with Iran, we'll get dragged down for 20 or 30 years. The world will condemn us. We will lose our position in the world."Zbigniew Brzezinski
http://www.vanityfair.com/politics/features/2006/07/yellowcake200607?currentPage=11