As you might expect, there are three options. Israel could bomb Iran, we could bomb Iran, or we could do nothing. Diplomacy counts as doing nothing becuase it will fail to acheive the appropriate goals. I suppose a fourth option would be to accept dhimmitude, but that is not something that I would prefer to think about.
Yet, were an air strike on Iran to take out say, only 10 of 15 sites, it would still severely retard the Iranian nuclear effort, buying the West time to formulate and enact either a policy of engagement from a position of strength, or a policy of regime change with the requisite credibility among regime opponents that such a strike would inspire.
The Mullahs are in a bind. On the one hand, they have a sharp sword in the form of oil cuts. On the other and, they need the money. They may be willing in principle to accept more damage to their economy, but in reality they need the money to pay for the things that keep their young and restless population partially sated...bread and circuses are expensive.
Were I in the Mullahs situation, I would try for a 20% cut in production. Right now, there are about 800,000 spare bpd of global production capacity. The Mullahs are producing a little over 4 million bpd of oil per day... about 5% of world capacity. They might even make money on the cut as oil prices would rise substantially.
Whatever the Mullahs do, expect Europe to roll over. Europe doesn't have the mability to affect world events anymore. Even if they did, Europe still sees the Jews as the real problem rather than their own unwillingness to contribute to the security of Western Civilization.