Iran, and the whole of the middle east began it’s journy backwards in time in 1979 when the Ayatollah emerged from under the exiled protection of the French and ran the Shaw of Iran out of power.
One only has to listen as crowds of thousands, as government organized rallies, shout of the Great Satan (the USA) to get a sense of their feelings toward America. Their statement toward Israel is the promise to “wipe Israel off the map”. Although there are several Muslim majority countries in the middle and far east Iran carries the special charge of being the only Islamic Caliphate supported by the structure of a theocracy based on Shariah, an archaic system of legal codes that include limb amputation the outlawing and execution of various minorities (gay men are routinely killed). In other words it is a Muslim country with no lingering desire to modernize in any social sense. They will dane to build nuclear bombs though.
They are the greatest supplier and monetary backer of militant Islamic movements across the world. They are the only state to boldly proclaim that they will be the tinder from which the flames of the final Armageddon will burst forth to kill all Jews as well as get even with the west for the crusades. Only world domination , a world Caliphate will signal an end to their Jihad.
The point is. Iran cannot be allowed to have nuclear weapons.