Guys in a way the game has already been played and Israel has lost. Call the Iranian government what you want. But they're damn good chess players. If Israel attacks, Iran will quite legitimately withdraw from the NPT and pursue a Nuclear weapons program. An Israeli attack will change the world public opinion in Iran's favor and will make it easier for some major states to openly throw their support behind her. Iran develops nuclear deterrence. Israel loses.
On the other hand, if Israel sits on its hands, Iran will become a de facto nuclear power in short order. Iran is already enriching to 20%. And from what I understand that constitutes the bulk of the effort needed for Highly Enriched Uranium. In other words the higher the enrichment level, the faster it becomes to enrich. Iran can enrich enough uranium and build Heavy water reactors like the one in Arak that use natural uranium and produce Plutonium as a byproduct, until it is one screw away from having a nuclear device. Once Iran stockpiles a large enough quantity of fissile material, the game will change. Israel loses again.
In either case, the world powers will have to somehow settle with Iran and neighbouring Arab regimes will have to fall in line. The center of gravity will shift in the region, away from Israel.
The only hope for Israel is to have America do their dirty work for them. And that is easier said than done. Americans don't have the stomach to start another major war in the middle east. And it's not a sure thing that even they can seriously delay the Iranian nuclear program. At this point it all sounds more like bluster and psychological warfare than a real threat of military action.
