Sabre rattling. What other options do they have? If the current treaty winds up in the trash, the only thing that will be proven to the Iranians is there is nothing they can do to end US sanctions.
Do you think the ayatollahs and the generals aren’t aware that are under active target? Israel wouldn’t even need to use their own nukes, you can bet we got 'em covered. Not to get started with the fact that this kinda scenario would indeed set off ww3.