I think we should stay out of it and not climb in bed with these criminals; every time we do it comes back to bite us. Besides, that corner of the planet is a clearing house for conventional weapons and these guys have all the dough they need to buy anything they want in any quantity.
Let them kill each other.
This is Iran, not Afghanistan.
Responding to Iran with words only has bitten us quite a bit IMO and for about 30 years.