If I was an Iranian looking around me, what do I see - Afghanistan and Iraq occupied by the world's biggest nuclear power (approx 6000+ warheads) (who say we are 'evil' and helped Saddam Hussain invade us the last time we were attacked causing massive loss of life), various ex-USSR States (3000 warheads), Pakistan (just acquired nukes in breach of NPT, pointed them at the world's biggest democracy, has not even declared a 'no first use' policy (unlike India) and got rewarded for it), US falling over backwards to accomodate North Korea (who claim to have nukes) and the biggest regional threat to our way of life Israel also with about 200 nukes acquired secretly in breach of NPT.
Hell if I was an Iranian I would for sure want a nuke.
Like I said the real worry isn't a state with nukes - no matter how 'mad' leaders are meant to be no-one is going to embark upon a nuclear exchange - it's nuclear material being made available to Islamic Terrorists that scares the hell out of me....that and the US army posturing about first use of 'mini-nukes' on the battlefield