OK, time to make my opinion on this.
And they would be. It's like Japan attacking Pearl Harbor. If Israel strikes first, it will indeed be devastating, but Iran is a very tough nation with 10x Israel's population and will certainly retaliate. They've got nearly 2.4M people ready to fight (active+reserve), while Israel has nearly 2.9M fit for service (that's overall civilians who could possibly sign up and get trained) with a current active+reserve of nearly 622K. NOT GOOD NUMBERS. Iran also has Russia, NK, and China on their side for potential support and aid. I'm pretty sure NK would gladly hand over a nuke early on.
Wait... you suppose Iran can transport It's whole army about 1500 k.m. by desert or about 2000 through non-desert?!?! Do you know what a logistical nightmare that is? They have a maximum of a few tens of thousands of transport vehicles. (http://en.wikipedia.org/wiki/Equipment_ … y#Vehicles)
So they'll move about 100,000 troops max if they don't make them walk all the way, and the column would be under constant threat of bombardment. At about 500 k.m. per day(and that's very optimistic for such a large force)It would take 4 days minimum. Also, that would be across neutral territory, so they'll probably scavenger, which would force the local populace against them. 4 days for bombardments is a lot, since the Iranian army couldn't intercept since their airport is far away.
also, tanks are not very mobile and wear out very fast, so they won't pass the trip on their own, at least not very fast. (http://en.wikipedia.org/wiki/Tank#Mobility) So conventional attacks on such scales are impossible.
Naval attacks would have two options- going through Gibraltar, the Suez or Eilat. The first two would have to go through Spain and Egypt respectively, and both would very much not like the territory passed through. The last one has two problems- it is possible to defend Eilat, and even if they get there, they won't do much damage. So naval attacks are not that helpful.
No nation has attacked another over nuclear weapons development,
Well, if 0=2, then yes.
http://en.wikipedia.org/wiki/Operation_Opera
http://en.wikipedia.org/wiki/Operation_Orchard
Get your facts straight.
Israel's missile shield pose enough of a deterrence without actually going to attack Iran.
Well, anti-rocket systems do not always work. For example, Israel's iron dome works a bit over 90% of the time, and that is to single missiles. The moment you have lots of them, the success rate drops.
it's a regional power and one that has quite a lot of leverage.
All of Iran's neighbors hate it. So yes, they have negative leverage.
USA did it
Usa did it for the questionable fact that it would save lives that would have perished during the attack of mainland Japan.
The main question for Israel stands upon is will the conventional attack destroy the facility or not.
Since the base is deep underground, it may not be harmed to the extent of being nonoperational. Every other question is more of less non-important.