Have China the guarantor, build military bases, and put them under their nuclear deterrence umbrella. Iran can be assured they won't be bombed, the West can be assured they won't have nukes. (in theory, I largely assume the CCP will not aid in their construction or let them have nukes under such an arrangement).

Thing is, all the little countries are looking at what happened to Ukraine (who gave up their nukes), Iran (who has not gotten them yet), and North Korea (who has them). Their looking and thinking, if I had nukes, I probably wouldn't be the target of regime change.