Osirak was a single facility, and a large one at that, completely above ground. Iran has their nuclear program scattered amongst God knows how many sites above ground and below. There is no way that you can guarantee that you will take them out with air strikes. But then after your days of air strikes then what do you expect Iran to do? Nothing? Or will they sink tankers, block the gulf, strike back at their neighbors and against us and Israel any way they can? Anyone who thinks that this is a short term, few day military operation is crazy. Airstrikes only begin the process that will eventually require ground troops. How many facilities can they have? My guess is the upper limit required for minimal efficiency is 100. We can take out 100 sites easy. Most of Saddam's army was intact after Desert Storm. We bombed his facilities repeatedly. He was never able to rebuild his nuclear program.