I don't think we will have to. The economy of Iran is fairly dismal right now, and it's people connected enough to have a pretty good idea of how much money their government is wasting on the support of terrorism. Strategically, the louder I'minajihad gets in the pissing contest with Hugo "Castro, jr" Chavez over who gets to represent the 3rd world at the UN, when combined with America's tolerance to his rhetoric that they are all witnessing just as we are, sprinkled with a dash of this crap has been going on for decades now and it's getting worse every day, then blended with a creamy mixture of we saw how quickly Iraq fell and we see what kind of mess that's created... still with me? ...then potentially baked in a Nuclear Furnace lit by Israeli smart-bombs is a good recipe for Iranian Civil War just like mom used to make.
Here's a nice little research article:
http://news.bbc.co.uk/1/hi/world/mid...st/4621699.stm
...and here's a sweet and thorough history:
http://www.atimes.com/atimes/Middle_East/HI23Ak01.html
Money Quote: "Keeping hands off Iran may be the best bet for the US administration's professed aim of "democratizing" the Middle East..."
...and finally, here's some general economic data ranging over the past 2-6 years that might paint a clearer picture of what might be cooking in that pot:
http://www.farsinet.com/news/
On that last one, skip down about half the page to the part about Cost Of Living. Note the age graph on the right from 2000. That big bubble of 10-19 year olds is now 6 years older, and 30% of them can't find jobs. Those that are employed can't afford a place of their own even if they work 2 jobs, generally, at least according to the what I'm seeing in the income chart to the left of the age chart.
The trend away from fundamentalism among the younger Iranian population, when combined with such stark proof of the failures of the Mullahs to effectively run a country while remaining a thorn in the side of the West, in my opinion, will soon lead to an overthrow of the status quo, which will likely be good for them as well as the world.
We'll wait it out. Worst case scenario, the test a nuke and Israel wipes out half the rural folk that voted I'minajihad in, sparing the students and the educated middle class that will embody the revolution. The leadership of Iran is playing to the average Arab, ignoring it's exceptional minority of almost Western already younger set. They do this at their peril. You don't see other successful Arab countries trying that.